Journal of Exercise and Nutrition
type: channel
description: The Journal of Exercise and Nutrition (JEN) is an open access, peer-reviewed journal that aims to enhance basic and applied research in multiple areas of exercise and nutrition from clinical to athletic populations. The journal provides researchers, practitioners, and students with a platform for novel and cutting-edge practices in the field. ISSN: 2640 - 2572.
publisher: Pinnacle Science
language: en
publication name: Journal of Exercise and Nutrition
issn: 2640-2572
copyright: Copyright, 2026 by the authors. This work is licensed under the Creative Commons Attribution 4.0 International License.
items: Blood Glucose Response During a 9-Hole Round of Golf for Collegiate Golfers
items: The Prevalence of Heart Rate Variability Monitoring Among a Sample of Habitual Runners
items: Parasympathetic Reactivation Following Maximal Exercise: Influence of Breathwork and Body Composition in ROTC Cadets
items: OligonolⓇ Increases the Distance Covered in the 12-Minute Run Test in Long-Distance Runners: A Randomized, Double-Blind, Placebo-Controlled, Parallel Trial
items: Association of Nutritional Knowledge, Practice, Supplement Use with Running Performance Among Long Distance Recreational Runners
items: Effect of β3-Adrenergic Receptor Gene Polymorphism on Aerobic Exercise-Induced Lipolytic Response
items: Dietary Behaviors, Nutrient Intake, and Rowing Performance in Collegiate Athletes: From a National Champion Team in Japan
items: Acute Citrulline Malate Supplementation Does Not Improve 1-km Time Trial Performance in Trained Female Kayak Paddlers
items: Analysis of Nutrition Knowledge and Healthy Habits within ROTC Cadets
items: https://journalofexerciseandnutrition.com/index.php/JEN/article/view/214
items: Substrate-Corrected VO₂ Models for Improved Interpretation of Movement Economy
items: Stress and Eating Behaviors Pre- and Post COVID-19 Pandemic Declaration in Two Independent Samples of College-Aged Adults
items: Optimizing Nitric Oxide Production for Exercise Performance & Vascular Function: A Narrative Review on the Combination of Glutathione and Citrulline
items: Effects of Sports Nutrition Counseling on Rating of Perceived Fatigue and Diet Patterns
items: Agreement Between Six Bioelectrical Impedance Analysis Devices and Dual-Energy X-Ray Absorptiometry
items: Navigating ROTC and Corps of Cadets’ Nutrition Knowledge and Perspectives on Dietary Intake and Behavior
items: Analysis of Dietary Micronutrient Intake of NCAA Track and Field Athletes
items: A Randomized, Double-Blind, Placebo-Controlled Evaluation of Coffea Arabica Seed Extract for Cognitive and Mood Impacts in Healthy Adults
items: Impact of Immersive Virtual Reality Exercise on Physiological and Psychological Outcomes in College Students: A Comparison with Traditional Cardiorespiratory Exercise
items: A Case Report: Compositional, Physiological, and Psychological Responses to Contest Preparation in a First-time Bikini Competitor
items: Acute Effects of Creatine and Branch Chain Amino Acids on Resting Energy Expenditure: Considerations for Testing
items: Selection of Sex Does Not Affect Body Composition When Using the InBody770 Bioelectrical Impedance Analysis
items: Exercise Behaviors and Nutrition Knowledge and Practices Among Trained Athletes: A Cross-Sectional Study
items: Evaluating the Effects of a Proprietary Water Formulation on Hydration and Physiological Responses During Exercise-Heat Stress in Active Adults
items: Risk of Low Energy Availability, Disordered Eating, Eating Disorders, and Bone Stress Injuries in United States Female Track and Field
items: The Omega-3 Index in Athletes
items: An Evaluation of Sports Nutrition Knowledge and Influencing Factors in NCAA Division III Athletes
items: Nutritional Preparation for an Ultra-Endurance Swimmer: A Case Report
items: A Pharmacokinetic Comparison of Three Butyrate Products
items: https://journalofexerciseandnutrition.com/index.php/JEN/article/view/188

Blood Glucose Response During a 9-Hole Round of Golf for Collegiate Golfers
type: item
description: Introduction: Competitive golf places substantial physical and cognitive demands on athletes. Prolonged walking, explosive movements, environmental stressors, and mental focus contribute to significant energy expenditure and fatigue during competition. Nutrition plays a critical role in supporting both physical performance and cognitive function. Maintaining stable blood glucose levels is especially important to performance, as fluctuations may impair endurance, decision making, and concentration. Therefore, the purpose of this study was to examine blood glucose responses in collegiate golfers during a 9-hole round of golf. Methods: Age, height, and weight were collected using a scale and stadiometer. All participants played 9 holes of golf while walking. Prior to the round of golf, participants completed a modified 24-hour food recall and a baseline blood glucose measurement. During the round, the participants were instructed to only consume water; blood glucose was collected after the completion of every hole. Results: Blood glucose levels declined progressively across the 9-hole round, with an average decrease of 9.2 mg/dL from baseline (91.6 ± 17.7 mg/dL) to post round (82.4 ± 9.1 mg/dL). Mean blood glucose decreased by approximately 0.95 mg/dL per hole (p < 0.001), with significant variation across holes and between individuals. Linear mixed effects modeling revealed a significant effect of hole on blood glucose (p < 0.001), with over half of the total variance attributable to between participant differences (ICC = 0.545). Conclusions: These findings highlight the need for individualized nutritional strategies to support golf performance. Collaborative, athlete specific nutrition approaches aimed at maintaining stable blood glucose levels may be essential for sustaining physical and cognitive performance throughout competitive play.
subject: Articles
  topic: section
subject: performance
  topic: keywords
subject: nutrition
  topic: keywords
subject: sports
  topic: keywords
subject: adults
  topic: subjects
subject: College golfers
  topic: subjects
subject: Exercise
  topic: disciplines
subject: nutrition
  topic: disciplines
subject: sports
  topic: disciplines
creator: Kaela Hierholzer
creator: Suzanne Bowser
rights: Copyright (c) 2026 Kaela M Hierholzer, Suzanne M Bowser https://creativecommons.org/licenses/by/4.0
date: 2026-03-25
publication date: 2026-03-25
doi: 10.53520/jen2026.103233

The Prevalence of Heart Rate Variability Monitoring Among a Sample of Habitual Runners
type: item
description: Introduction: The measurement of heart rate variability (HRV) draws widespread attention among athletes and researchers, but few data are available on the use and application of HRV in runners. The purpose of this study was to examine the prevalence of HRV monitoring and the adjustment of training based on HRV among a sample of habitual runners. Methods: Runners (18-65 yr) who reported running ≥3 d·wk-1 for ≥6 months and competing in ≥2 races annually completed a 13-item survey on training habits and the use of wearable devices. Chi-square analysis was used to detect differences in the prevalence of HRV monitoring between genders, age groups, and competitive levels. Unpaired t-tests were used to compare training frequency (d∙wk-1), volume (hr∙wk-1), and experience (years running) between HRV trackers and nontrackers and between competitive and noncompetitive runners. Statistical significance was accepted at p≤0.05. Results: Out of N=210 respondents (17.7±8.81 yr experience, 3.78±0.98 d∙wk-1 frequency), 47% (n=99) reported regularly monitoring HRV. More HRV users (χ2=4.89, p=0.027) were male (57.6%, n=57) than female (42.4%, n=42). HRV monitoring was similar between “competitive” vs. “recreational” runners (χ2=0.486, p=0.49). 71% of HRV trackers used Garmin© devices while only 20% reported adjusting training based on HRV. Conclusions: HRV measurement is prevalent among runners, but is not frequently used to alter training.
subject: Articles
  topic: section
subject: wearables
  topic: keywords
subject: running
  topic: keywords
subject: heart rate variability
  topic: keywords
subject: Adults
  topic: subjects
subject: Runners
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
subject: Sports
  topic: disciplines
creator: Andrew J. Carnes
creator: Sara E. Mahoney
rights: Copyright (c) 2026 Andrew Carnes, Sara E. Mahoney https://creativecommons.org/licenses/by/4.0
date: 2026-03-27
publication date: 2026-03-27
doi: 10.53520/jen2026.103231

Parasympathetic Reactivation Following Maximal Exercise: Influence of Breathwork and Body Composition in ROTC Cadets
type: item
description: Introduction: Autonomic recovery is critical for tactical readiness. While structured breathwork enhances parasympathetic reactivation, it is unclear whether body composition indices such as percent body fat (%BF) or fat-free mass index (FFMI) influence acute recovery following maximal exertion. This study examined whether %BF or FFMI moderate post-exercise autonomic recovery in ROTC cadets. Methods: Fifty-two cadets (age 20.0 ± 3 yrs; %BF 28.5 ± 7.7; FFMI 18.4 ± 2.8) completed a maximal rowing test and were randomized to box breathing (BB, n = 19), cyclic sighing (CS, n = 17), or spontaneous breathing (SB, n = 16) during a 3-min active recovery. HF-HRV was measured at baseline, 1–3 min, and 4–6 min post-exercise. HRR was calculated at 1 and 3 min. Repeated-measures MANOVA and %BF- and FFMI-adjusted MANCOVA were performed. Results: A significant main effect of time was observed for HF-HRV (Pillai’s Trace = .934, F(2,48) = 339.86, p < .001). The Time × Group interaction reached significance in the FFMI-adjusted model (Pillai’s Trace = .190, F(4,96) = 2.52, p = .046). Time × %BF and Time × FFMI interactions were non-significant (p ≥ .271). Regression analyses showed BB and CS predicted higher HF-HRV at Post1 (R² = .193) and Post2 (R² = .224; p ≤ .017), whereas %BF and FFMI were not significant predictors. HRR demonstrated a main effect of time (p < .001) without group or body composition effects. Conclusions: Structured breathwork enhanced post-exercise parasympathetic reactivation independent of %BF and FFMI. Body composition did not significantly influence acute autonomic recovery in this cohort.
subject: Articles
  topic: section
subject: fat-free mass
  topic: keywords
subject: box breathing
  topic: keywords
subject: cyclic sighing
  topic: keywords
subject: vagal tone
  topic: keywords
subject: VO2max
  topic: keywords
subject: Adults
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
creator: Mark Jones
creator: Geneveive Smith
creator: Anthony Acevedo
creator: Bridget Melton
rights: Copyright (c) 2026 Mark Jones, Geneveive Smith, Anthony Acevedo, Bridget Melton https://creativecommons.org/licenses/by/4.0
date: 2026-03-20
publication date: 2026-03-20
doi: 10.53520/jen2026.103232

OligonolⓇ Increases the Distance Covered in the 12-Minute Run Test in Long-Distance Runners: A Randomized, Double-Blind, Placebo-Controlled, Parallel Trial
type: item
description: Introduction: Oligonol® which is a standardized oligomerized-polyphenol from Litchi chinensis fruit extract (OPLFE), has been reported to have multiple beneficial effects on exercise performance. This study evaluated the effects of OPLFE on endurance performance in long-distance runners. Methods: A randomized, double-blind, placebo-controlled, parallel trial was conducted in which 34 long-distance runners (male and female adults aged 45–64) were assigned to receive 200 mg/day of OPLFE or placebo as the intervention for 60 days. The 12-minute run tests were conducted at the initial and final visits to evaluate the primary outcome (running distance), and secondary outcomes included heart rate, rating of perceived exertion (RPE) score, and body composition. Statistical significance was set at *P < 0.05. Results: The primary outcome of running distance in the 12-minute run test was significantly increased in the OPLFE group compared to the placebo group (OPLFE: 2.97 ± 0.36 km vs. placebo: 2.95 ± 0.36 km, P = 0.038), based on an analysis of covariance with baseline value as the covariate and group as the factor. The secondary outcome of RPE score also showed a significant decrease in the OPLFE group compared to the placebo group (OPLFE: 14.5 ± 2.0 vs. placebo: 16.4 ± 2.0, P = 0.003). No differences were observed in the other secondary outcomes. Conclusions: OPLFE intake increased the distance covered in the 12‑minute run test and reduced RPE. These findings suggest that OPLFE may improve endurance performance in middle‑aged male and female adults.
subject: Articles
  topic: section
subject: endurance performance
  topic: keywords
subject: lychee fruit polyphenol
  topic: keywords
subject: running distance
  topic: keywords
subject: nutrition
  topic: keywords
subject: Adults
  topic: subjects
subject: Males
  topic: subjects
subject: Females
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
subject: Supplements
  topic: disciplines
creator: Takuma Shio
creator: Manami Misu
creator: Kazunori Goto
creator: Yukiko Fukuchi
creator: Ken Ishii
creator: Jun Takanari
rights: Copyright (c) 2026 Takuma Shio, Manami Misu, Kazunori Goto, Yukiko Fukuchi, Ken Ishii, Jun Takanari https://creativecommons.org/licenses/by/4.0
date: 2026-03-12
publication date: 2026-03-12
doi: 10.53520/jen2026.103225

Association of Nutritional Knowledge, Practice, Supplement Use with Running Performance Among Long Distance Recreational Runners
type: item
description: Introduction: Limited evidence exists on whether nutritional knowledge, practice, and supplement use relate to running performance in recreational distance runners. This cross-sectional study examined associations between nutritional knowledge, practice, and supplement use with race time performance among recreational long-distance runners. Methods: A total of 160 recreational runners (72.5% male, mean age not reported) who completed the Hong Kong Marathon 2024 completed an online questionnaire assessing nutritional knowledge, practice, and supplement use. Race times were self-reported. Linear regression and independent t-tests were used to examine associations with completion time. Results: Across all distance categories, correlations between nutritional knowledge and completion time were weak and non-significant (10 km: r = 0.146, p = 0.448; half-marathon: r = 0.228, p = 0.111; full marathon: r = −0.027, p = 0.813). Similarly, correlations between nutritional practice and completion time were weak and non-significant (10 km: r = 0.004, p = 0.985; half-marathon: r = −0.092, p = 0.527; full marathon: r = −0.051, p = 0.649). There were no significant differences in race times between supplement users and non-users in any distance category (10 km: p = 0.818; half-marathon: p = 0.121; full marathon: p = 0.992). A substantial proportion of participants reported poor nutritional knowledge (48.1%) and practice scores (36.9%). Conclusions: This study found no significant associations between nutritional knowledge, practice, or supplement use and race time performance among recreational long-distance runners. The high prevalence of poor nutritional knowledge and practice highlights a need for nutrition education among runners. Future research using objective measures and controlling for training volume and experience is needed.
subject: Articles
  topic: section
subject: Exercise Nutrition
  topic: keywords
subject: Sports Performance
  topic: keywords
subject: Long-Distance Running
  topic: keywords
subject: Adults
  topic: subjects
subject: Runners
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
subject: Performance
  topic: disciplines
creator: Siu Chuen Pang
rights: Copyright (c) 2026 Siu Chuen Pang https://creativecommons.org/licenses/by/4.0
date: 2026-01-28
publication date: 2026-01-28
doi: 10.53520/jen2026.103221

Effect of β3-Adrenergic Receptor Gene Polymorphism on Aerobic Exercise-Induced Lipolytic Response
type: item
description: Introduction: Diet and exercise interventions reduce the risk of obesity; however, fat loss varies across individuals. During moderate-intensity aerobic exercise, norepinephrine stimulates adipose lipolysis via β3-adrenergic receptors (β3AR). The β3AR Trp64Arg polymorphism has been linked to reduced lipolytic responsiveness. This study examined whether Trp64Arg influences fat breakdown during aerobic exercise in young women. We hypothesized that Trp64Arg carriers (Trp/Arg) would show a blunted rise in circulating free fatty acids (FFA) and higher respiratory quotient (RQ; VCO₂/VO₂) during exercise than that of non-carriers (Trp/Trp). Methods: Thirty-seven healthy female university students (20–23 years) completed 40 min of cycling at 55 W after a standardized dinner and 12-h fast. Serum FFA, energy expenditure, and RQ were measured at rest and during exercise. Participants were genotyped and classified as wild-type (Trp/Trp; n = 29) or heterozygous (Trp/Arg; n = 8). Repeated-measures analyses tested group, time, and group × time effects; estimated marginal means were used for model-based summaries. Results: Serum FFA at 40 min increased compared to that of rest in both groups, but reached significance only in the wild-type group (2.04 ± 1.25 vs 0.90 ± 0.48 mEq/L, p = 0.009). During exercise, RQ differed according to genotype (main effect of group: p = 0.003; group × time: p = 0.065), with higher RQ in heterozygous participants (0.91 ± 0.02, 95% CI 0.88–0.94) than in the wild-type group (0.86 ± 0.01, 95% CI 0.84–0.88). Conclusions: In young women, carrying the Trp64Arg polymorphism of the β3AR gene potentially contributes to a blunted lipolytic response and relatively high reliance on carbohydrate metabolism during moderate-intensity aerobic exercise.
subject: Articles
  topic: section
subject: Trp64Arg polymorphism
  topic: keywords
subject: free fatty acids
  topic: keywords
subject: respiratory quotient
  topic: keywords
subject: adults
  topic: subjects
subject: females
  topic: subjects
subject: cycling
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
subject: Performance
  topic: disciplines
subject: Cycling
  topic: disciplines
creator: Shiho Kondo
creator: Kotoyo Fujiki
rights: Copyright (c) 2026 Shiho Kondo, Kotoyo Fujiki https://creativecommons.org/licenses/by/4.0
date: 2026-02-07
publication date: 2026-02-07
doi: 10.53520/jen2026.103222

Dietary Behaviors, Nutrient Intake, and Rowing Performance in Collegiate Athletes: From a National Champion Team in Japan
type: item
description: Introduction: Competitive rowers train at high volumes and intensities and therefore require well-structured nutritional support. However, it remains unclear how everyday dietary behaviors and habitual dietary intake patterns relate to rowing performance. Methods: In this cross-sectional study, 33 male collegiate rowers from a national champion team in Japan completed a food frequency questionnaire and additional items assessing nutrition-related behaviors and awareness. Performance outcomes included personal-best 2,000-m rowing ergometer time and official competition ranking at a national university championship. Results: Four behaviors, use of low-fat milk, frequent legume/soy consumption, seeking nutrition information, and perceived dietary adequacy, were significantly associated with faster 2,000-m ergometer times (rho ρ = 0.35–0.40, p = 0.032–0.044). In addition, a higher plant-protein ratio was associated with better official competition ranking (rho ρ = -0.48, p = 0.017). Conclusions: These findings suggest that both everyday nutrition-related behaviors and habitual dietary intake patterns were associated with rowing performance and underscore the potential value of nutrition education and support in this population.
subject: Articles
  topic: section
subject: plant protein
  topic: keywords
subject: nutrition knowledge
  topic: keywords
subject: ergometer time
  topic: keywords
subject: Adults
  topic: subjects
subject: Rowers
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
subject: Sports
  topic: disciplines
subject: Performance
  topic: disciplines
creator: Kazuki Mitsuyama
creator: Tadashi Abe
creator: Kimiyasu Hayakawa
rights: Copyright (c) 2026 Kazuki Mitsuyama, Tadashi Abe, Kimiyasu Hayakawa https://creativecommons.org/licenses/by/4.0
date: 2026-01-24
publication date: 2026-01-24
doi: 10.53520/jen2026.103220

Acute Citrulline Malate Supplementation Does Not Improve 1-km Time Trial Performance in Trained Female Kayak Paddlers
type: item
description: Introduction: Citrulline malate (CM) has been reported to enhance performance during resistance training and high-intensity exercise; however, its ergogenic effects during kayak exercise have not been investigated. This study examined the effects of acute CM ingestion on 1-km kayak ergometer time-trial (TT) performance and ratings of perceived exertion (RPE) in trained female youth kayakers. Methods: Fifteen trained female youth kayakers (age: 16.3 ± 1.1 y; body mass: 55.5 ± 6.7 kg; height: 164.3 ± 3.7 cm) completed three conditions in a randomized, double-blind, placebo-controlled crossover design: CM (8 g), placebo (PL; 6 g citric acid), and a control condition (CON; no supplement). Participants ingested CM and PL 60 min before a 1-km kayak ergometer TT. RPE (6–20) was recorded immediately upon TT completion. Results: The TT completion time differed across conditions (p = 0.001; ηp² = 0.44). Compared with CON (270.8 ± 5.31 s), TT was faster following CM (262.6 ± 4.69 s; p = 0.016) and PL (261.8 ± 4.55 s; p < 0.001), with no difference between CM and PL (p = 1.000). The RPE also differed across conditions (p = 0.025; ηp² = 0.23); however, Bonferroni-adjusted pairwise comparisons did not reach statistical significance (CON vs CM: p = 0.080; CON vs PL: p = 0.107; CM vs PL: p = 1.000). Conclusion: Acute CM supplementation did not improve 1-km kayak ergometer TT performance compared with placebo in trained female youth kayakers. The faster times observed in both CM and placebo compared with control may reflect non-specific effects (e.g., placebo/taste or pre-trial routines) and warrant further investigation.
subject: Articles
  topic: section
subject: Exercise performance
  topic: keywords
subject: nitric oxide
  topic: keywords
subject: ergogenic aids
  topic: keywords
subject: Adults
  topic: subjects
subject: Trained
  topic: subjects
subject: Females
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
subject: Supplementation
  topic: disciplines
creator: Majid Koozehchian
creator: Shima Mojtahedi
creator: Russ Best
creator: Raúl Domínguez
creator: Mohammad Ali Gharaat
creator: Erfan Berjisian
creator: Andrew Newton
creator: Gina Mabrey
creator: Alireza Naderi
rights: Copyright (c) 2026 Majid Koozehchian, Shima Mojtahedi, Russ Best, Raúl Domínguez, Mohammad Ali Gharaat, Erfan Berjisian, Andrew Newton, Gina Mabrey, Alireza Naderi https://creativecommons.org/licenses/by/4.0
date: 2026-02-16
publication date: 2026-02-16
doi: 10.53520/jen2026.103217

Analysis of Nutrition Knowledge and Healthy Habits within ROTC Cadets
type: item
description: Introduction: In pursuit of achieving and maintaining military readiness, Reserve Officers’ Training Corps (ROTC) cadets must adhere to the standards of body composition and physical fitness respective to their service. Healthy habits such as adequate nutrition, sleep, and physical activity are essential for supporting these outcomes in service members, but evidence suggests that ROTC cadets may face challenges achieving optimal dietary intake and quality, in addition to having lower scores of nutrition knowledge, and are at increased risk of disordered eating. Methods: Sixty-eight cadets (85 percent male; mean age 19.1±1.1 years) from a southeastern university completed the Military Eating Behaviors Survey (MEB-S). This study reported descriptive statistics of the survey responses related to nutrition, physical activity, and sleep. Further correlations among nutrition knowledge, diet quality, frequency of meal consumption, physical activity and sleep were analyzed. Results: The mean HES-7 score was 16.9±6.6, indicating suboptimal diet quality. More than half the sample reported supplement use within the past 30 days. Average sleep duration was 6.9±2.1 hours per night, and vigorous physical activity reported 41.8 days out of the week for 1.5±0.9 hours while moderate activity reported an average 3.5±2.1 days a week for 1.3±1.0 hours. Nutrition knowledge scores (14.5±3.0) were not significantly correlated with diet quality, meal frequency, frequency of meal consumption, physical activity or sleep. Data reports a moderate statistically significant negative association between diet quality and hours of sleep (HES-5, Pearson’s r = -0.414, p < .001; HES-7, Pearson’s r = -0.389, p = .002; HES-9, Pearson’s r = -0.449, p < .001). Conclusions: These findings suggest that ROTC cadets exhibit generally poor diet quality and high supplement use. This sample reported an average nutrition knowledge, although they had formal nutrition education provided. However, analysis suggests …
subject: Articles
  topic: section
subject: Tactical Athlete
  topic: keywords
subject: diet intake
  topic: keywords
subject: Cadets
  topic: subjects
subject: adults
  topic: subjects
subject: ROTC
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Performance
  topic: disciplines
subject: Nutrition
  topic: disciplines
creator: Lara Barksdale
creator: Morgan Krupp
creator: Brooke Gilmore
creator: Hyun-Woo Joung
creator: Melinda Valliant
creator: Corbit Franks
rights: Copyright (c) 2026 Lara Barksdale , Morgan Krupp, Brooke Gilmore , Dr. Hyun-Woo (David) Joung, Dr. Melinda W Valliant, Dr. Corbit Franks https://creativecommons.org/licenses/by/4.0
date: 2026-02-07
publication date: 2026-02-07
doi: 10.53520/jen2026.103215

https://journalofexerciseandnutrition.com/index.php/JEN/article/view/214
type: item
title: Effects of Casein Hydrolysate Containing Val-Pro-Pro and Ile-Pro-Pro on Muscle Pump, Muscle Hypertrophy, and Motivation in Resistance-Trained Men: A Placebo-Controlled, Double-Blind, Parallel-Group Comparison Study
description: Introduction: The purpose was to investigate the effects of lactotripeptides (LTP) immediately after training. Methods: This randomized, placebo-controlled, double-blind, parallel-group comparison study included males who undertook leg strength training every 2 weeks for ≥3 months. Thirty-six participants received placebo, low-dose (LD) (Val-Pro-Pro 0.7 mg/Ile-Pro-Pro 1.0 mg) or high-dose (HD) (Val-Pro-Pro 1.4 mg/Ile-Pro-Pro 2.0 mg) lactotripeptides daily for 4 weeks. Muscle pump, muscle hypertrophy, fatigue, and training motivation were evaluated. Results: In the HD group, thigh circumference before exercise, lean body mass versus baseline and thigh circumference after exercise versus placebo significantly increased (p=0.002, 0.031, 0.032). In the LD group, subjective questionnaire scores related to muscle pump versus placebo significantly improved (p=0.042). Thigh circumference changes, before and after exercise, and subjective questionnaire scores, regardless of dosage, significantly correlated (p=0.026). Individuals with flow-mediated dilation (FMD) <7% showed a trend toward increased FMD in the HD group (p=0.081). Significant positive correlation occurred between FMD changes and thigh circumference, before and after exercise (p=0.021). In the HD group, fatigue scores after exercise and motivation for training scores the morning after exercise versus placebo significantly improved (p=0.020, 0.043). Conclusions: LTP intake may be beneficial for muscle pump after training and muscle hypertrophy, reduce training-induced fatigue, and enhance strength training motivation. Key Words: fatigue; lactotripeptide; strength training Corresponding author: takuro.ohigashi@asahi-gf.co.jp
subject: Articles
  topic: section
subject: lactotripeptide
  topic: keywords
subject: fatigue
  topic: keywords
subject: strength training
  topic: keywords
subject: adults
  topic: subjects
subject: exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
subject: Supplementation
  topic: disciplines
creator: Takuro Ohigashi
creator: Koki Sato
creator: Misaki Hatanaka
creator: Masaaki Yasue
creator: Shohei Nakashima
creator: Yuri Miyamoto
creator: Yumi Aoyagi
creator: Shukuko Ebihara
creator: Toshiharu Namba
creator: Motoyuki Tagashira
rights: Copyright (c) 2026 Takuro Ohigashi, Koki Sato, Misaki Hatanaka, Masaaki Yasue, Shohei Nakashima, Yuri Miyamoto, Yumi Aoyagi, Shukuko Ebihara, Toshiharu Namba, Motoyuki Tagashira https://creativecommons.org/licenses/by/4.0
date: 2026-01-07
publication date: 2026-01-07
doi: 10.53520/jen2026.103214

Substrate-Corrected VO₂ Models for Improved Interpretation of Movement Economy
type: item
description: Introduction: Movement economy is a core metric in endurance performance, yet conventional interpretation overlooks substrate-specific oxygen costs. Elevated oxygen consumption (VO₂) is often misclassified as reduced efficiency when it may instead reflect adaptive increases in fat oxidation. This report introduces and evaluates normalization approaches designed to yield more physiologically valid interpretations of oxygen consumption. Methods: This conceptual, simulation-based, and secondary data analysis developed two substrate-corrected VO₂ models: (1) the RER-Based Energy Equivalent (RER-EE) model, which adjusts VO₂ for varying caloric yields per liter of oxygen across RER values, and (2) the RER-Based Substrate Partitioning with Substrate Correction Ratio (RER-SP+SCR) model, which partitions VO₂ by substrate and corrects the fat-derived fraction for its lower ATP yield per O₂. Both were applied to previously published datasets from endurance athletes under diverse metabolic conditions. Results: Both models produced appreciably different normalized VO₂ values compared to traditional methods, particularly under high-fat oxidation conditions. The largest corrections occurred during prolonged submaximal efforts, such as 13KM and 25KM trials, reducing bias that would otherwise misclassify fat-adapted athletes as less economical. Conclusions: Substrate-corrected normalization provides a physiologically valid framework for interpreting oxygen consumption, enhancing research and applied assessments of endurance performance, training adaptation, and metabolic health.
subject: Articles
  topic: section
subject: Energy Metabolism
  topic: keywords
subject: Substrate Utilization
  topic: keywords
subject: Oxygen Consumption
  topic: keywords
subject: Adults
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
creator: Bronson Dant
creator: Peter Cummings
creator: Timothy Noakes
creator: Philip Prins
rights: Copyright (c) 2025 Bronson Dant, DHSc(c), CSCS, CCFT, Peter Cummings, MHP, Timothy Noakes, MBChB, MD, DSc, PhD(hc), Philip Prins, PhD. https://creativecommons.org/licenses/by/4.0
date: 2025-11-03
publication date: 2025-11-03
doi: 10.53520/jen2025.103212

Stress and Eating Behaviors Pre- and Post COVID-19 Pandemic Declaration in Two Independent Samples of College-Aged Adults
type: item
description: Introduction: This study compared stress and eating behaviors of two independent samples of college students before and after declaration of the COVID-19 pandemic to understand pandemic-related changes in these health-related behaviors. Methods: This was a non-experimental comparative study using a between-subjects design. Two independent groups were invited to the laboratory for a single visit to measure eating behaviors and stress indicators. Four validated instruments were used in this study: The Weight and Lifestyle Inventory questionnaire, Mindfulness Eating Questionnaire, Three-Factor Eating Questionnaire (TFEQ), and the Perceived Stress Scale (PSS). Independent t-tests and two-way ANOVA were used to compare participants who were tested prior to the COVID-19 pandemic declaration and after. Results: N=151 (n=81 male, n=70 female) participants completed testing in the pre-COVID group, and a separate group, N=79, completed testing in the post-COVID group (n=40 male and n=26 female). There was a significant difference in TFEQ-uncontrolled eating between groups by sex (F(1,207)=4.73, p =.031, ƞ2=.022). There were differences between the pre-COVID and post-COVID groups (F(1,204)=5.64, p 019, ƞ2=.027) and between sexes (F(1,204)=16.84, p <0.001, ƞ2=.076) on the TFEQ-emotional eating. The post-COVID group reported higher levels of eating when stressed, depressed/upset, anxious, and when alone compared to the pre-COVID group (all p <.05). There were sex differences in eating when stressed, depressed/upset, anxious, and when alone (all p <.05). PSS scores were significantly higher in the post-COVID group (p =.003). Females (20.4±5.4) reported higher stress than males (17.8±6.3) (p =.003). Conclusions: College students assessed after the pandemic declaration showed higher stress levels and emotional eating scores. Female college students reported higher stress and emotional eating levels than males.
subject: Articles
  topic: section
subject: Emotional eating
  topic: keywords
subject: Psychological distress
  topic: keywords
subject: Gender differences
  topic: keywords
subject: Adults
  topic: subjects
subject: males
  topic: subjects
subject: females
  topic: subjects
subject: Exercise
  topic: disciplines
subject: nutrition
  topic: disciplines
creator: Zachary Zeigler
creator: Anthony Acevedo
creator: Annika Myers
creator: Ruthie Marson
creator: Jeb Johnston
rights: Copyright (c) 2025 Zachary Zeigler, Anthony Acevedo, Annika Myers, Ruthie Marson, Jeb Johnston https://creativecommons.org/licenses/by/4.0
date: 2026-01-01
publication date: 2026-01-01
doi: 10.53520/jen2026.103211

Optimizing Nitric Oxide Production for Exercise Performance & Vascular Function: A Narrative Review on the Combination of Glutathione and Citrulline
type: item
description: Introduction: Citrulline has been thoroughly researched and well documented to increase plasma arginine levels, boosting nitric oxide (NO) synthesis via the nitric oxide synthase (NOS) pathway. While glutathione, a key antioxidant, protects NO from oxidative degradation and helps maintain vascular signaling integrity. When taken together, these nutrients may offer enhanced and/or sustained NO bioavailability, supporting vascular function, recovery, and exercise performance more effectively than citrulline alone. Methods: A literature review was conducted to explore the relationships between glutathione, citrulline, NO, and vascular health. Three databases, PubMed, ScienceDirect, and Google Scholar and eight search terms were used to find relevant articles. Results: Four double-blind placebo controlled human clinical trials found the combination of glutathione and l-citrulline to be more effective in enhancing and sustaining NO production levels and flow mediated dilation (vasodilation) better than citrulline alone (P<0.03). Conclusions: Collectively, these studies support the functional synergy between citrulline and glutathione in promoting NO-related health and performance outcomes offering a promising nutritional strategy for athletes, aging individuals, and those seeking cardiovascular support.
subject: Articles
  topic: section
subject: Antioxidants
  topic: keywords
subject: Sports Nutrition
  topic: keywords
subject: Nitric Oxide
  topic: keywords
subject: Flow Mediated Dilation
  topic: keywords
subject: Humans
  topic: subjects
subject: Adults
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
subject: Supplements
  topic: disciplines
creator: Katie Emerson
rights: Copyright (c) 2025 Katie M. Emerson https://creativecommons.org/licenses/by/4.0
date: 2025-09-09
publication date: 2025-09-09
doi: 10.53520/jen2025.103210

Effects of Sports Nutrition Counseling on Rating of Perceived Fatigue and Diet Patterns
type: item
description: Introduction: Collegiate cross-country runners have poor dietary intakes and are at increased risk for injury. Fatigue is one outcome used to predict risk of injury, and improvement in dietary intakes such as increased carbohydrate consumption may result in reduced fatigue. Other factors such as academic stress, sleep, and muscle mass also contribute to fatigue in athletes. Methods: Nutrient intake, perceived fatigue, sleep quality, and changes in body composition were assessed for nine cross-country athletes before and after receiving sports nutrition counseling. As this is a case series type design, these data, along with notes from nutrition counseling, were analyzed for trends with a focus on energy intake, carbohydrate intake, and factors that impact day-to-day fatigue. Results: Participants (n=9) had minimal changes in perceived fatigue, sleep quality, and body composition during the study. Most participants met estimated requirements for energy (106%) and protein (150%) but only consumed 70% of estimated carbohydrate needs. Participants made an effort to increase carbohydrate intake and reported reduced fatigue on long runs after increasing carbohydrates. Conclusions: Nutrition counseling from a registered dietitian can help to improve timing and quality of carbohydrates. Nutrition may improve peripheral fatigue experienced by athletes, but other factors impacting central fatigue should be assessed when reporting overall fatigue in athletes.
subject: Articles
  topic: section
subject: running
  topic: keywords
subject: energy
  topic: keywords
subject: endurance
  topic: keywords
subject: adults
  topic: subjects
subject: athletes
  topic: subjects
subject: exercise
  topic: disciplines
subject: nutrition
  topic: disciplines
creator: Gabriella Matney Matney
creator: Carrie Hamady
creator: Amy Morgan
rights: Copyright (c) 2025 Gabriella M. Matney, Dr. Carrie M. Hamady, Dr. Amy L. Morgan https://creativecommons.org/licenses/by/4.0
date: 2025-10-17
publication date: 2025-10-17
doi: 10.53520/jen2025.103207

Agreement Between Six Bioelectrical Impedance Analysis Devices and Dual-Energy X-Ray Absorptiometry
type: item
description: Introduction: Bioelectrical impedance analysis (BIA) is a low-cost, accessible method to assess percent body fat (%BF). Rising recognition of the role of body composition in overall health and disease prevention has led to an increased usage of at-home BIA devices. The purpose of this study was to assess the level of agreement between six BIA devices and dual-energy x-ray absorptiometry (DXA). Methods: Male (n=42) and female (n=35) participants completed body composition testing on six different BIA devices and a DXA scan Agreement was assessed using intraclass correlation coefficients (ICC) with 95% confidence intervals, Spearman’s correlations, and Bland-Altman analyses to determine limits of agreement (LoA) for %BF. Results: Four BIA devices demonstrated moderate reliability (ICC: 0.66-0.73) and two devices demonstrated poor reliability (ICC: 0.25 and 0.43). The most favorable agreement profile from a BIA device was a mean bias of -2.21% and relatively narrow LoA (-9.88% - 5.46%). The least favorable agreement profile from a BIA device was a mean bias of 2.88% and LoA of –10.25% –16.01%. Conclusions: The present study indicated that multi-frequency BIA devices outperformed single-frequency BIA devices, and that the Omron had the highest LoA with DXA.
subject: Articles
  topic: section
subject: Body composition assessment
  topic: keywords
subject: body fat percentage
  topic: keywords
subject: Adults
  topic: subjects
subject: Males
  topic: subjects
subject: Females
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
creator: Gena Irwin
creator: Ariel Aguiar Bonfim Cruz
creator: Alexa Chandler
creator: C.J. Brush
creator: Ann Frost Brown
rights: Copyright (c) 2025 Ann Frost Brown, Ariel Aguiar Bonfim Cruz, Alexa Chandler, C.J. Brush, Gena Irwin https://creativecommons.org/licenses/by/4.0
date: 2025-09-09
publication date: 2025-09-09
doi: 10.53520/jen2025.103206

Navigating ROTC and Corps of Cadets’ Nutrition Knowledge and Perspectives on Dietary Intake and Behavior
type: item
description: Introduction: Reserve Officer Training Corps (ROTC) and Corps of Cadets face unique challenges that make them susceptible to poor nutritional habits. We evaluated cadets’ dietary beliefs, habits, barriers, and food choices, as well as general and sport nutrition knowledge. Methods: Cross-sectional data were analyzed from 184 members of the University’s ROTC and Corps of Cadets, using validated questionnaires, including the Nutrition Knowledge Questionnaire for Athletes (NKQA), the Food Choice Questionnaire (FCQ), the Rapid Eating Assessment for Participants, Shortened Version (REAP-S), and the Perceived Barriers to Healthy Eating. The categorical data were reported as frequencies (n) and percentages, and Chi-square (χ2) analyses were used to determine group independence (p < 0.05). Continuous data were checked for normality and then analyzed for differences between sexes and commission status using independent samples t-tests or Mann-Whitney U tests. Effects sizes were calculated using Cohen’s d and interpreted as follows: <0.2 trivial, <0.5 small, <0.8 moderate, <1.2 large, and >1.2 very large. Results: Participants exhibited poor overall nutrition knowledge (37.3±14.2%), with low scores for carbohydrates = 31.9±15.6%, protein = 52.6±20.7%, fat = 40.6±24.1%, vitamins = 35.3±23.2%, general nutrition = 29.1±14.6%, fluid = 28.8±20.4%, and sport nutrition = 36.2±17.5%. Further, the participants expressed being very willing (n=79, 42.9%) or willing (n=79, 42.9%) to change their dietary habits to healthier ones. However, a busy lifestyle (n = 164, 89.1%) and limited cooking facilities (n = 104, 56.5%) presented significant challenges to healthy eating. Conclusions: The participants reported having poor nutrition knowledge but valued healthier eating and expressed a willingness to improve their dietary habits to healthier ones. These findings suggest cadets may benefit from practical, registered dietitian nutritionist (RDN)-supported nutrition educational interventions th…
subject: Articles
  topic: section
subject: Military
  topic: keywords
subject: Food Choice
  topic: keywords
subject: Nutrition, Diet
  topic: keywords
subject: Tactical Athlete
  topic: keywords
subject: Military
  topic: subjects
subject: Cadets
  topic: subjects
subject: Adults
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
creator: Sheyla Leon
creator: Adriana Gil
creator: Ryan J. Sowinski
creator: Lisa C. Colvin
creator: Steven E. Martin
creator: Stella L. Volpe
creator: Drew E. Gonzalez
rights: Copyright (c) 2025 Sheyla Leon, Adriana Gil, Ryan J. Sowinski, Lisa C. Colvin, Steven E. Martin, Stella L. Volpe, Drew E. Gonzalez https://creativecommons.org/licenses/by/4.0
date: 2025-09-29
publication date: 2025-09-29
doi: 10.53520/jen2025.103204

Analysis of Dietary Micronutrient Intake of NCAA Track and Field Athletes
type: item
description: Introduction: Micronutrients are critical to optimal physiological function of the human body’s overall health and homeostasis. An athlete’s performance and recovery may be inhibited by micronutrient deficiencies1. This study analyzed the micronutrient consumption of National Collegiate Athletic Association (NCAA) Division I Collegiate Track and Field athletes. Methods: Thirty-seven track and field athletes, 15 females and 22 males participated. Multiple 24-hr recalls were collected, including weekdays and weekends, and analyzed using Nutrition Data System for Research (NDSR) to obtain dietary micronutrient intakes. Average intakes were compared to the Recommended Dietary Allowance (RDA) for each micronutrient. Pearson Chi Squared tests were used to assess correlations amongst the participant characteristics, gender, age, race, track event group, and residence. Results: Many participants under-consumed micronutrients, most commonly magnesium, calcium, and vitamin D. Significant correlations were found between gender and iron intake, race and magnesium intake, and residence and calcium intake. Results indicated a significant relationship between gender and dietary iron intake (p < 0.001), residence and calcium consumption (p < .05), and the race and magnesium intake (p < .05). Males were more likely to meet the iron RDA, and Caucasians had higher magnesium intake than African Americans. Those living on-campus were more likely to meet calcium requirements than off-campus. Conclusions: These findings highlight the need for dietary education and the importance of assessing micronutrient intake. While the impact of these nutrients on athletic performance justifies such efforts, their broader implications for overall health reinforce the necessity of thorough dietary analysis. Athletic programs should evaluate micronutrient intake alongside total caloric and macronutrient consumption.
subject: Articles
  topic: section
subject: Athletes
  topic: keywords
subject: Nutrition
  topic: keywords
subject: Performance
  topic: keywords
subject: Athletes
  topic: subjects
subject: Male
  topic: subjects
subject: Female
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
creator: Haley Melton
creator: Corbit Franks
creator: Tyler Myers
creator: Samantha Kostelnik
creator: Hyun-Woo Joung
creator: Melinda Valliant
rights: Copyright (c) 2025 Haley Melton, Dr. Corbit Franks, Tyler Myers, Dr. Samantha Kostelnik, Dr. Hyun-Woo (David) Joung, Dr. Melinda W Valliant https://creativecommons.org/licenses/by/4.0
date: 2025-08-08
publication date: 2025-08-08
doi: 10.53520/jen2025.103203

A Randomized, Double-Blind, Placebo-Controlled Evaluation of Coffea Arabica Seed Extract for Cognitive and Mood Impacts in Healthy Adults
type: item
description: Introduction: NeuroRush™ is a dietary ingredient comprised of the seed extract of the Coffea arabica. It is rich in polyphenols and chlorogenic acid (CGA). CGAs are linked to positive health impacts and are believed to support cognitive function. This study aimed to determine if a dietary supplement made of Coffee arabica seed extract would affect cognitive function and mood states in healthy adults. Methods: In a randomized, double-blind, placebo-controlled crossover trial, 19 healthy adults consumed either NeuroRush™ (150 mg coffee seed extract) or placebo (150 mg of maltodextrin). Participants completed cognitive tests (Go/No-Go, Stroop, and N-Back), subjective mood assessments, and safety monitoring at baseline and 1-, 2-, and 3 hours post-ingestion. Results: Significant main effects of time were observed for cognitive performance across tasks, including improvements in Stroop total score (p = 0.016), Stroop reaction time (p = 0.013), and N-Back correct responses (p = 0.010). The NeuroRush™ group exhibited enhanced N-Back accuracy (p = 0.008, d = 0.85) and a trend toward faster overall Go reaction times. Self-reported well-being was significantly greater in the NeuroRush™ group at 3 hours compared to placebo (p = 0.047, d = 0.64). Conclusions: Acute ingestion of NeuroRush™ may mildly enhance cognitive performance, particularly working memory and processing efficiency, and improve well-being in healthy adults. NeuroRush™ was well-tolerated and was safe within the confines of the study design. Longer-term research is warranted to determine if the enhanced cognitive impacts and mood states remain over time.
subject: Articles
  topic: section
subject: chlorogenic acid
  topic: keywords
subject: polyphenols
  topic: keywords
subject: cognition
  topic: keywords
subject: mood
  topic: keywords
subject: coffee
  topic: keywords
subject: Adults
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
creator: Cassandra Evans
creator: Doug Kalman
rights: Copyright (c) 2025 Cassandra Evans, Doug Kalman https://creativecommons.org/licenses/by/4.0
date: 2025-06-26
publication date: 2025-06-26
doi: 10.53520/jen2025.103202

Impact of Immersive Virtual Reality Exercise on Physiological and Psychological Outcomes in College Students: A Comparison with Traditional Cardiorespiratory Exercise
type: item
description: Introduction: Research suggests virtual reality (VR) exercise could be useful in promoting physical activity, particularly among college students who often engage with video games. The aim of this study was to compare physiological and psychological effects of immersive VR exercise to traditional cardiorespiratory exercise. Methods: Twenty-four participants completed two separate 20-minute exercise sessions (immersive VR exercise and cardio equipment of choice) in a randomized and counter-balanced order. Average and maximum heart rate, perceived exertion, and psychological outcomes of enjoyment, intrinsic motivation, and mood were assessed. Results: There was no significant difference in heart rate parameters or perceived exertion indicating similar exercise intensity between both sessions. However, the VR session resulted in significantly greater enjoyment (p<.001), improved mood (tension p=.011, depression p=.026, vigor p<.001, happiness p=.003), higher interest/enjoyment and perceived competence (p<.001 and p=.018, respectively), and less effort (p=.022) compared to traditional exercise. Conclusions: VR exercise is a highly motivating and enjoyable alternative to traditional exercise and could be a valuable tool for improving physical activity and mental well-being in college-aged individuals. Future research should investigate different VR exercise modalities and long-term effects to optimize VR’s potential in sustaining physical activity.
subject: Articles
  topic: section
subject: Physical activity
  topic: keywords
subject: mood
  topic: keywords
subject: motivation
  topic: keywords
subject: Adults
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
creator: Renee Harrington
rights: Copyright (c) 2025 Renee Harrington https://creativecommons.org/licenses/by/4.0
date: 2025-06-01
publication date: 2025-06-01
doi: 10.53520/jen2025.103201

A Case Report: Compositional, Physiological, and Psychological Responses to Contest Preparation in a First-time Bikini Competitor
type: item
description: Introduction: The purpose of this report was to document a novice, natural, female, physique athlete’s physiological and psychological responses to a 6-month preparation and 1-month post-competition period. Methods: The athlete’s protocol throughout preparation was a high-protein caloric deficit with ~2 refeed days per week, as well as resistance and cardiovascular training. The athlete self-reported bodyweight and adherence via a weekly electronic survey. Once monthly during preparation, compositional, physiological, and psychological assessments were administered by a technician. Blood samples were drawn at the beginning of preparation and during the week of competition. Results: Bodyweight decreased throughout preparation (51.9 to 46.7kg; Δ5.2kg) and further post-competition (46.3kg, R2=0.96), with a similar decrease in body fat percentage (17.2 to 12.3%; Δ4.9%) and fat-free mass (42.9 to 41.0kg; Δ1.9kg) during preparation. Mild somatic (8/30) and depressive (5/27) symptoms manifested approximately 1-month prior to competition. Depressive (7/27) and anxiety (5/21) symptoms peaked post-competition but were not clinically significant. This aligned with a peak in emotional eating post-competition (5/12) and an increase in the athlete’s previously elevated cortisol levels (761.76 to 839.04nmol/L). Conclusions: The present report may be the first empirical documentation of a female physique competitor reducing fat-free mass during contest preparation and what is anecdotally known as “post-show blues.”
subject: Articles
  topic: section
subject: Dieting
  topic: keywords
subject: Bodybuidling
  topic: keywords
subject: Fat loss
  topic: keywords
subject: female
  topic: subjects
subject: adult
  topic: subjects
subject: nutrition
  topic: disciplines
subject: exercise
  topic: disciplines
subject: weight loss
  topic: disciplines
creator: Alexa Rukstela
creator: Kworweinski Lafontant
creator: Bill Campbell
rights: Copyright (c) 2025 Alexa Rukstela, Kworweinski Lafontant, Dr. Bill I. Campbell https://creativecommons.org/licenses/by/4.0
date: 2025-04-29
publication date: 2025-04-29
doi: 10.53520/jen2025.103200

Acute Effects of Creatine and Branch Chain Amino Acids on Resting Energy Expenditure: Considerations for Testing
type: item
description: Introduction: The purpose of this study to was to elucidate the potential effects of acute creatine monohydrate (CM) and branched chain amino acid (BCAA) ingestion on resting energy expenditure (REE). Methods: Young physically active individuals (n=60) were randomly allocated to a single treatment: 1) Placebo (PL), 2) CM, or 3) BCAA. Participants completed a REE test via indirect calorimetry to establish baseline REE prior to ingesting their corresponding treatment. A post-REE was then conducted 60-mins after treatment consumption. Estimate daily caloric expenditure at rest was compared between treatments. Results: PL consumption did not result in changes of REE from pre- (1691 ± 360) to post-ingestion (1671 ± 319; p= 0.395; d= 0.06). However, acute ingestion of BCAA (p= 0.008; d= 0.12) resulted in significantly higher REE pre- (1678 ± 401) versus post- (1761 ± 357) . A non-significant trend towards decreases in REE were noted pre- (1663 ± 421) to post- (1590 ± 346) for CM (p=0.056; d=0.17). The magnitude of the effects for all conditions were small or trivial. These findings suggest that while the popular supplements CM and BCAAs alter REE acutely, the small changes may not be practically important to consider for REE testing. Conclusions: While the effects were small, individualized considerations for REE testing may still be necessary, but further testing using larger and more diverse sample sizes are needed.
subject: Articles
  topic: section
subject: Supplements
  topic: keywords
subject: Metabolism
  topic: keywords
subject: Indirect Calorimetry
  topic: keywords
subject: adults
  topic: subjects
subject: exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
creator: Lia Jiannine
creator: Zachary H. Ervin
creator: Christopher G. Ballmann
rights: Copyright (c) 2025 Lia Jiannine, Zachary H. Ervin , Christopher G. Ballmann https://creativecommons.org/licenses/by/4.0
date: 2025-04-05
publication date: 2025-04-05
doi: 10.53520/jen2025.103199

Selection of Sex Does Not Affect Body Composition When Using the InBody770 Bioelectrical Impedance Analysis
type: item
description: Introduction: Many methods and equations for assessing body composition include sex as a variable. However, sex and gender identity do not always align. Thus, it would be beneficial to have easily performed methods of measuring body composition that did not rely on sex as a component of the assessment. For this purpose, the current study tested whether the InBody770 requires sex input to accurately measure body composition in males and females. Methods: Cisgender men and women were recruited to the study to have their body composition assessed in duplicate. Assessments were performed in a random order. ANOVAs were performed on the data reported from the InBody770 both within subjects and between groups. Results: There were no within subject differences for percent body fat (33.6 vs. 33.5 and 15.1 vs. 15.1%), estimated basal metabolic rate (1,438 vs. 1,440 and 1,842 vs. 1,842kcals/day), nor total body water (36.15 vs. 36.24 and 49.89 vs. 49.92 L) regardless of whether their sex was assigned as male or female. There were significant sex differences for percent body fat (33.5 vs. 15.1%), metabolic rate (1,438 vs. 1,842kcals), and total body water (36.15 vs. 49.92L regardless of how the individuals were identified (male or female). Conclusions: While average sex differences in percent body fat existed between males and females, the imputation of sex on the InBody770 did not influence the data produced.
subject: Articles
  topic: section
subject: Body fat
  topic: keywords
subject: BIA
  topic: keywords
subject: Gender
  topic: keywords
subject: Adults
  topic: subjects
subject: Students
  topic: subjects
subject: Exercise
  topic: disciplines
subject: nutrition
  topic: disciplines
subject: body composition
  topic: disciplines
creator: Douglas Oberlin
creator: Adam Mohan
creator: Yea Been Kim
creator: Levi Vazquez
creator: Jane Ekhtman
rights: Copyright (c) 2025 D.J. Oberlin, Adam Mohan, Yea Been Kim , Levi Vazquez , Jane Ekhtman https://creativecommons.org/licenses/by/4.0
date: 2025-04-09
publication date: 2025-04-09
doi: 10.53520/jen2025.103198

Exercise Behaviors and Nutrition Knowledge and Practices Among Trained Athletes: A Cross-Sectional Study
type: item
description: Introduction: Nutritional supplementation is a common strategy used by athletes at all levels of sport to enhance mental and physical performance and to improve recovery; however, it is difficult to generalize dietary supplement use as studies on the topic are heterogeneous. This cross-sectional study aims to collect current data on aspects related to exercise behaviors and nutrition knowledge and practices in trained athletes in the United States. Methods: Purposive sampling was utilized to recruit participants in the target population. A pilot-questionnaire was used to create the valid, reliable final questionnaire that was implemented. Descriptive statistics were used to summarize data. A chi-square test of independence was performed to examine relationships between selected variables. Results: Details on frequency, intensity, time, and type of exercise were summarized for the respondents. A majority responded as having basic or average nutrition knowledge. Nutrition knowledge and frequency of nutritional product use was also summarized. There was a significant relationship between selected variables with lower level and frequency of muscle soreness associated with higher frequency of engagement in recovery activities, higher level and frequency of muscle soreness associated with higher average intensity of both cardio- and strength-based exercise sessions, and a higher level of nutrition knowledge associated with a higher implementation of nutritional focus before, during, and after exercise. Conclusions: The results of the present study provide valuable information on aspects related to exercise behaviors and nutrition knowledge and practices in trained athletes. Future research should continue to investigate the use of supplements for athletic performance as well as investigate distinct nutrition knowledge compared to self-reported level of knowledge of nutrition.
subject: Articles
  topic: section
subject: supplementation
  topic: keywords
subject: training measures
  topic: keywords
subject: performance
  topic: keywords
subject: Athletes
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
creator: Renee Harrington
rights: Copyright (c) 2025 Renee Harrington https://creativecommons.org/licenses/by/4.0
date: 2025-03-12
publication date: 2025-03-12
doi: 10.53520/jen2025.103197

Evaluating the Effects of a Proprietary Water Formulation on Hydration and Physiological Responses During Exercise-Heat Stress in Active Adults
type: item
description: Introduction: Hypohydration can impair physical and cognitive performance, particularly in hot and humid conditions or after intense activity. Hydration solutions aim to maintain euhydration and minimize electrolyte loss, yet the efficacy of a proprietary water (PW) formulation remains unclear. This study compared its effects on hydration status and performance to a carbohydrate-electrolyte drink (CE) and distilled water (DW), hypothesizing that CE would enhance hydration markers, perceptual responses, and cognitive and physiological outcomes. Methods: Thirty-seven physically active males and females (25±7 years, 19 females) were randomized into PW (n=12), CE (n=13), or DW (n=12). Participants consumed 3.7 L (males) or 2.7 L (females) of their assigned fluid for five days before completing two 45-minute treadmill protocols simulating soccer play (28-33°C, 40-50% RH). Fluids lost were replenished at halftime. Cognitive assessments and subjective questionnaires were administered. A repeated measures linear mixed effects model analyzed group differences (α=0.05). Results: Time significantly affected serum osmolality (p=0.009), lactate (p<0.001), vasopressin (p=0.003), and cortisol (p<0.001), but no significant group effects were found (p>0.05). The PW participants reported a higher RPE post-exercise than DW (p=0.041), with no other significant cognitive or perceptual differences. Conclusion: None of the fluids significantly impacted hydration status or performance variables. Future research may examine longer exercise durations or more extreme conditions to reveal potential differences.
subject: Articles
  topic: section
subject: Thermoregulation
  topic: keywords
subject: cognition
  topic: keywords
subject: rehydration
  topic: keywords
subject: active males
  topic: subjects
subject: active females
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
creator: Blaine Lints
creator: Jacob Eade
creator: Gianna Mastrofini
creator: Courtney Meyer
creator: Sten Stay-Gundersen
creator: Alexa Chandler
creator: Bridget McFadden
creator: Nathaniel Rhoades
creator: Robert Moore
creator: Shawn Arent
creator: Susan Yeargin
rights: Copyright (c) 2025 Blaine S. Lints, Jacob M. Eade, Gianna F. Mastrofini, Courtney M. Meyer, Sten Stay-Gundersen, Alexa J. Chandler, Bridget A. McFadden, Nathaniel D. Rhoades, R. Davis Moore, Shawn M. Arent, Susan W. Yeargin https://creativecommons.org/licenses/by/4.0
date: 2025-03-12
publication date: 2025-03-12
doi: 10.53520/jen2025.103195

Risk of Low Energy Availability, Disordered Eating, Eating Disorders, and Bone Stress Injuries in United States Female Track and Field
type: item
description: Introduction: Female track and field athletes have increased risk of low energy availability (LEA), disordered eating (DE), and eating disorders (ED), which are associated with health and performance consequences. This study explored LEA, DE, and ED risk among United States female track and field athletes and assessed differences in proportions between risk and competition level and bone stress injury (BSI) risk. Methods: Female track and field athletes (n = 392, aged 18-68 years) completed an online survey including the Low Energy Availability in Females Questionnaire (LEAF-Q), Eating Disorder Examination Questionnaire (EDE-Q), and Female Athlete Screening Tool (FAST), and self-reported BSIs. Chi-square tests of homogeneity assessed differences in proportions between competition level and BSI and LEA, DE, and ED risk. Results: 49%, 48%, and 22% of participants had high risk for LEA, DE, and ED, respectively; and concurrent risk of LEA, DE, and ED was 27%. There was a significant difference in proportions between competition level and LEA risk (X2 (3, 387) = 11.93, p = 0.008, Φ= 0.176) and ED/DE risk (X2 (3, 387) = 11.65, p = 0.007, Φ= 0.213); and BSI and LEA risk (X2 (2, 392) = 8.58, p = 0.014, Φ= 0.148). Conclusions: This study demonstrated a considerable portion of US female track and field athletes had high risk of LEA, DE, and ED.
subject: Articles
  topic: section
subject: Runners
  topic: keywords
subject: Nutrition
  topic: keywords
subject: Injury
  topic: keywords
subject: Female
  topic: subjects
subject: Athletes
  topic: subjects
subject: Track and Field
  topic: subjects
subject: Exercise
  topic: disciplines
subject: Nutrition
  topic: disciplines
creator: Melissa Lodge
creator: Steve Cirella
creator: Mark Hartman
creator: Nicole Logan
creator: Christie Ward-Ritacco
rights: Copyright (c) 2025 Melissa T. Lodge, Steve M. Cirella, Dr. Mark E. Hartman, Dr. Nicole E. Logan, Dr. Christie L. Ward-Ritacco https://creativecommons.org/licenses/by/4.0
date: 2025-02-28
publication date: 2025-02-28
doi: 10.53520/jen2025.103192

The Omega-3 Index in Athletes
type: item
description: Introduction: The omega-3 index (O3i), the amount of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) as a percentage of total fatty acids within erythrocytes, has emerged as a potentially important biomarker for sport. The purpose of this review is to quantify the O3i in athletes across various sporting contexts. Methods: Two databases (PubMed, Google Scholar) were searched for cross-sectional studies reporting the O3i in athletes. Simple pooled mean analyses were used to quantify the O3i in all studies and by subgroup (i.e., sex and sport). Results: Based on 18 studies (25 observations) comprised of 1,452 athletes, the combined O3i was 4.43 ± 0.59% and ranged between 2.98% and 5.19%. According to studies that reported the O3i proportion within their sample, less than 1% of all athletes had an O3i > 8%, whereas 32% of athletes had an O3i < 4%. The O3i mean difference between all subgroups (sex and sport activity) was within ± 1%. Conclusions: Athlete programs should make a concerted effort to: 1) routinely test the O3i, 2) provide education from nutrition professionals on the potential benefits and sources of n-3 fatty acids and, 3) provide meal options comprised of rich sources of EPA and DHA at least three times per week and consider providing supplementation as needed, if allowed by governing organizations.
subject: Articles
  topic: section
subject: Biomarker
  topic: keywords
subject: performance
  topic: keywords
subject: sports nutrition
  topic: keywords
subject: eicosapentaenoic acid
  topic: keywords
subject: docosahexaenoic acid
  topic: keywords
subject: Adults
  topic: subjects
subject: athletes
  topic: subjects
subject: males
  topic: subjects
subject: females
  topic: subjects
subject: exercise
  topic: disciplines
subject: nutrition
  topic: disciplines
subject: sports
  topic: disciplines
subject: Supplementation
  topic: disciplines
creator: Jeffery Heileson
creator: Tina Sergi
creator: Leticia C. de Souza
rights: Copyright (c) 2025 Jeffery L. Heileson, Tina E. Sergi, Leticia C. de Souza https://creativecommons.org/licenses/by/4.0
date: 2025-04-21
publication date: 2025-04-21
doi: 10.53520/jen2025.103194

An Evaluation of Sports Nutrition Knowledge and Influencing Factors in NCAA Division III Athletes
type: item
description: Introduction: This study evaluated the sports nutrition knowledge of NCAA Division III (DIII) athletes, examining the influence of demographic and sport-specific factors. Nutrition is a critical component of athletic performance, recovery, and overall health, yet prior research indicates collegiate athletes often lack adequate nutrition knowledge. Methods: A total of 412 athletes, representing 17 different sports across endurance, power, and skill categories, completed the validated Abridged Nutrition for Sport Knowledge Questionnaire (A-NSKQ). The sample included freshmen through fifth-year senior athletes, predominantly Caucasian (85%). Results: The average A-NSKQ score was 17.1 out of 35 (48.9%), indicating suboptimal knowledge. Significant differences were found across multiple variables including sex (p=0.0018), class rank (p=0.0023), sport played (p<0.0001), and previous nutrition education (p=0.0011). A multiple regression analysis identified sport played (54%), class rank (16%), sex (13%), and prior nutrition education (11%) as significant predictors of A-NSKQ scores (R2 = 0.26, p < 0.01). Conclusions: These results highlight the need for targeted, evidence-based nutrition education in DIII programs. Future research should explore how improved knowledge influences dietary practices, athletic performance, and effective delivery of nutritional education.
subject: Articles
  topic: section
subject: nutrition
  topic: keywords
subject: athletes
  topic: keywords
subject: college
  topic: keywords
subject: athletes
  topic: subjects
subject: adults
  topic: subjects
subject: exercise
  topic: disciplines
subject: nutrition
  topic: disciplines
creator: Kerrie Berends
creator: Michael Wierenga
creator: Madeline Frens
rights: Copyright (c) 2025 Kerrie Berends, Michael J. Wierenga, Madeline Frens https://creativecommons.org/licenses/by/4.0
date: 2025-01-24
publication date: 2025-01-24
doi: 10.53520/jen2025.103191

Nutritional Preparation for an Ultra-Endurance Swimmer: A Case Report
type: item
description: Introduction: Nutritional considerations and metabolic determinates for ultra-endurance events continue to evolve with the increasing popularity of events. This case study assessed the nutritional requirements required of 30-year-old male ultra-endurance athlete to successfully complete an endurance open-water swim. Methods: Dietary intake in preparation for the event was assessed, estimated caloric needs, and a nutritional analysis was performed on the athlete to determine nutritional intake that was required to successfully complete the endurance swim event. The athlete was monitored for 24.3 miles (Ontario, Canada to Northeast, Pennsylvania, United States). Day of nutritional changes were observed, and body composition was assessed pre- and post-event. Results: The swimmer was monitored for 11 hours, 28 minutes and 5 seconds. Determination of athletes’ potential metabolic energy would shape the energy cost to complete the endurance event. Modifications prior to the ultra-endurance swim event met the athlete’s energy requirement for training and the energy reserve needed for the endurance swim event. Conclusions: The addition of calories and nutritional modifications prior to the ultra-endurance swim event met the athlete’s energy requirement for training and the energy reserve needed for the endurance swim event. This case study highlights the importance of providing nutritional support for ultra-endurance athletes and the difficulty in predicting energy expenditure for such an event.
subject: Articles
  topic: section
subject: nutrition
  topic: keywords
subject: caloric expenditures
  topic: keywords
subject: swimming efficiency
  topic: keywords
subject: College student
  topic: subjects
subject: Adults
  topic: subjects
subject: Exercise
  topic: disciplines
subject: nutrition
  topic: disciplines
subject: sports
  topic: disciplines
creator: Suzanne Kitts
creator: Kory Stauffer
creator: Tania Flink
rights: Copyright (c) 2025 Suzanne Kitts, Kory Stauffer, https://creativecommons.org/licenses/by/4.0
date: 2025-01-15
publication date: 2025-01-15
doi: 10.53520/jen2025.103190

A Pharmacokinetic Comparison of Three Butyrate Products
type: item
description: Introduction: The aim of this study was to compare the pharmacokinetic (PK) parameters of lysine butyrate (LysB) to sodium (NaB) and tributyrin (TB). Methods: Ten men (29.1 ± 10.4yr) completed this randomized, three-arm, crossover clinical trial (#NCT06700785) over four visits (a screening and three testing visits). Serum butyrate and indices of affect (well-being, calm/relaxed, stressed/anxious, mood, motivation to perform tasks, alertness, and concentration) were measured prior to product ingestion, and 20-, 45-, 90-, 150-, and 210-min post-ingestion. Each butyrate product delivered a total amount of 786 mg of butyric acid. Results: There was a trend for an interaction (p=0.095) for serum butyrate concentrations, however there were no post hoc differences over time or between treatments. NaB (144±214µg/mL/min, p=0.042, d=0.75) and LysB (189±306µg/mL/min, p=0.023, d=0.86) had a significantly greater AUC0-210 than TB (108±190µg/mL/min). NaB (2.51±4.13µg/mL, p<0.001, d=1.66) and LysB (4.53±7.56µg/mL, p=0.007, d=1.11) had a significantly greater Cmax than TB (0.91±1.65µg/mL). NaB (22.5±7.91min, p=0.008, d=1.21) and LysB (20.0±0.0min, p=0.004, d=1.45) had a significantly lower Tmax than TB (51.5±21.7min). There was a main effect of time for well-being (p=0.005), calm and relaxed (p=0.013), mood (p=0.002), motivation to perform tasks (p=0.040), alertness (p=0.035), and a treatment trend for concentration (p=0.063) while there were no differences between treatments over time for stressed and anxious (p>0.10). Conclusions: This study is among the first to simultaneously evaluate three commercially available butyrate formulations in a controlled setting, which may help inform formulation-specific therapeutic strategies in the future. This PK study demonstrates that LysB and NaB exhibit greater bioavailability and more rapid systemic appearance compared to TB.
subject: Articles
  topic: section
subject: short chain fatty acids
  topic: keywords
subject: pharmacokinetics
  topic: keywords
subject: gut-brain axis
  topic: keywords
subject: lysine
  topic: keywords
subject: tributyrin
  topic: keywords
subject: adults
  topic: subjects
subject: males
  topic: subjects
subject: exercise
  topic: disciplines
subject: nutrition
  topic: disciplines
creator: Michael La Monica
creator: Trevor Kirby
creator: Shelley Hartshorn
creator: Ashley Gustat
creator: Jodi Grdic
creator: Jennifer Sandrock
rights: Copyright (c) 2025 Michael La Monica, Trevor Kirby, Shelley Hartshorn, Ashley Gustat, Jodi Grdic, Jennifer Sandrock https://creativecommons.org/licenses/by/4.0
date: 2025-01-20
publication date: 2025-01-20
doi: 10.53520/jen2025.103189

https://journalofexerciseandnutrition.com/index.php/JEN/article/view/188
type: item
title: A Dietary Supplement Containing Essential Amino Acids in Combination with Resistance Training Improves Body Composition and Physical Performance Parameters in Generally Healthy Adults: A Pragmatic Single Arm Study
description: Introduction: Essential amino acid (EAA) supplements are popular for increasing muscle mass and improving performance. Methods: This pragmatic single arm study enrolled 30 participants (17F/13M) to consume a commercially available supplement providing 3.6 g/d EAA + arginine and complete supervised strength training (two, upper-body days, two, lower body days/week) over a 10-week period. DXA body composition, muscular strength (1 repetition max [1RM]) muscular endurance (number of repetitions to failure), and the Acute Recovery and Stress Scale (ARSS) were assessed at baseline and week 10. Results: Participants (n=27 completers [15F/12M]; mean ± SD age 38.7 ± 8.6 y and BMI 29.4 ± 3.6 kg/m2) experienced statistically significant (p<0.05) reductions in total fat mass (-0.9 [-1.8, -0.1] kg) and visceral fat (-96 [-165, -26] g), with concurrent increases in total lean body mass (1.1 [0.4, 1.8] kg), upper body strength (~18% increase in bench press 1-RM), lower body strength (~40% increase in angled leg-press 1-RM), and muscular endurance (~75% increased repetitions to failure for both exercises). Additionally, participants demonstrated improvements in all stress and recovery outcomes within the ARSS. Conclusions: These results demonstrate the potential value of EAA supplementation as part of a comprehensive approach to support physical performance and body composition in previously untrained or recreationally trained adults.
subject: Articles
  topic: section
subject: lean body mass
  topic: keywords
subject: muscular strength
  topic: keywords
subject: protein
  topic: keywords
subject: adults
  topic: subjects
subject: exercise
  topic: disciplines
subject: nutrition
  topic: disciplines
creator: Chad Cook
creator: Rob Missman
creator: Kristin Morris
rights: Copyright (c) 2025 Chad Cook, Rob Missman, Kristin Morris https://creativecommons.org/licenses/by/4.0
date: 2025-02-15
publication date: 2025-02-15
doi: 10.53520/jen2025.103188