Parasympathetic Reactivation Following Maximal Exercise: Influence of Breathwork and Body Composition in ROTC Cadets Original Research
Main Article Content
Keywords
fat-free mass, box breathing, cyclic sighing, vagal tone, VO2max
Abstract
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.
References
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3. Cornell DJ, Noel SE, Zhang X, Ebersole KT. Influence of Body Composition on Post-Exercise Parasympathetic Reactivation of Firefighter Recruits. Int J Environ Res Public Health. 2021;18(1):339. doi:10.3390/ijerph18010339
4. Shaffer F, Ginsberg JP. An Overview of Heart Rate Variability Metrics and Norms. Front Public Health. 2017;5:258. doi:10.3389/fpubh.2017.00258
5. Peçanha T, Silva‐Júnior ND, Forjaz CL de M. Heart rate recovery: autonomic determinants, methods of assessment and association with mortality and cardiovascular diseases. Clin Physiol Funct Imaging. 2014;34(5):327-339. doi:10.1111/cpf.12102
6. Cvijetic S, Keser I, Jurasović J, et al. Diurnal Salivary Cortisol in Relation to Body Composition and Heart Rate Variability in Young Adults. Front Endocrinol (Lausanne). 2022;13. doi:10.3389/fendo.2022.831831
7. Acevedo A, Zeigler Z, Melton B. Body Composition as a Predictor of Performance on the Army Combat Fitness Test Total Score for ROTC Cadets. Journal of Exercise and Nutrition. 2024;7(1). doi:10.53520/jen2024.103158
8. Pihlainen K, Santtila M, Häkkinen K, Lindholm H, Kyröläinen H. Cardiorespiratory Responses Induced by Various Military Field Tasks. Mil Med. 2014;179(2):218-224. doi:10.7205/MILMED-D-13-00299
9. Pletcher ER, Lovalekar M, Coleman LC, Beals K, Nindl BC, Allison KF. Decreased Percent Body Fat but Not Body Mass is Associated with Better Performance on Combat Fitness Test in Male and Female Marines. J Strength Cond Res. 2023;37(4):887-893. doi:10.1519/JSC.0000000000004335
10. Pihlainen K, Santtila M, Häkkinen K, Kyröläinen H. Associations of Physical Fitness and Body Composition Characteristics With Simulated Military Task Performance. J Strength Cond Res. 2018;32(4):1089-1098. doi:10.1519/JSC.0000000000001921
11. Nevill AM, Winter EM, Ingham S, Watts A, Metsios GS, Stewart AD. Adjusting athletes’ body mass index to better reflect adiposity in epidemiological research. J Sports Sci. 2010;28(9):1009-1016. doi:10.1080/02640414.2010.487071
12. Friedl KE. Body Composition and Military Performance—Many Things to Many People. J Strength Cond Res. 2012;26(Supplement 2):S87-S100. doi:10.1519/JSC.0b013e31825ced6c
13. Abu Hanifah R, Mohamed MohdNA, Jaafar Z, et al. The Correlates of Body Composition with Heart Rate Recovery after Step Test: An Exploratory Study of Malaysian Adolescents. PLoS One. 2013;8(12):e82893. doi:10.1371/journal.pone.0082893
14. Nogueira EC, Porto LGG, Nogueira RM, et al. Body Composition is Strongly Associated With Cardiorespiratory Fitness in a Large Brazilian Military Firefighter Cohort. J Strength Cond Res. 2016;30(1):33-38. doi:10.1519/JSC.0000000000001039
15. Jabbour G, Iancu HD. Supramaximal-Exercise Training Improves Heart Rate Variability in Association With Reduced Catecholamine in Obese Adults. Front Physiol. 2021;12. doi:10.3389/fphys.2021.654695
16. Papadakis Z, Grandjean PW, Forsse JS. Effects of Acute Exercise on Cardiac Autonomic Response and Recovery in Non-Dialysis Chronic Kidney Disease Patients. Res Q Exerc Sport. 2023;94(3):812-825. doi:10.1080/02701367.2022.2057401
17. Sztajzel J, Golay A, Makoundou V, et al. Impact of body fat mass extent on cardiac autonomic alterations in women. Eur J Clin Invest. 2009;39(8):649-656. doi:10.1111/j.1365-2362.2009.02158.x
18. Amato A, Petrigna L, Sortino M, Musumeci G. Visceral Fat Affects Heart Rate Recovery but Not the Heart Rate Response Post-Single Bout of Vigorous Exercise: A Cross-Sectional Study in Non-Obese and Healthy Participants. Sports. 2024;12(12):323. doi:10.3390/sports12120323
19. Sergi TE, Voelkel OM, Deehl CE, Jagim AR, Heileson JL. Normative fat-free mass index values based on body composition method in Army personnel. Performance Nutrition. 2025;1(1):10. doi:10.1186/s44410-025-00012-8
20. Hull HR, Thornton J, Wang J, et al. Fat-free mass index: changes and race/ethnic differences in adulthood. Int J Obes. 2011;35(1):121-127. doi:10.1038/ijo.2010.111
21. Zaccaro A, Piarulli A, Laurino M, et al. How Breath-Control Can Change Your Life: A Systematic Review on Psycho-Physiological Correlates of Slow Breathing. Front Hum Neurosci. Frontiers Media S.A. 2018;12. doi:10.3389/fnhum.2018.00353
22. Vlemincx E, Abelson JL, Lehrer PM, Davenport PW, Van Diest I, Van Den Bergh O. Respiratory variability and sighing: A psychophysiological reset model. Biol Psychol. 2013;93(1):24-32. doi:10.1016/j.biopsycho.2012.12.001
23. Balban MY, Neri E, Kogon MM, et al. Brief structured respiration practices enhance mood and reduce physiological arousal. Cell Rep Med. 2023;4(1). doi:10.1016/j.xcrm.2022.100895
24. Jerath R, Edry JW, Barnes VA, Jerath V. Physiology of long pranayamic breathing: Neural respiratory elements may provide a mechanism that explains how slow deep breathing shifts the autonomic nervous system. Med Hypotheses. 2006;67(3):566-571. doi:10.1016/j.mehy.2006.02.042
25. Picard M, McEwen BS, Epel ES, Sandi C. An energetic view of stress: Focus on mitochondria. Front Neuroendocrinol. 2018;49:72-85. doi:10.1016/j.yfrne.2018.01.001
26. Röttger S, Theobald DA, Abendroth J, Jacobsen T. The Effectiveness of Combat Tactical Breathing as Compared with Prolonged Exhalation. Appl Psychophysiol Biofeedback. 2021;46(1):19-28. doi:10.1007/s10484-020-09485-w
27. Lehrer P, Kaur K, Sharma A, et al. Heart Rate Variability Biofeedback Improves Emotional and Physical Health and Performance: A Systematic Review and Meta Analysis. Applied Psychophysiology Biofeedback. Springer. 2020;45(3):109-129. doi:10.1007/s10484-020-09466-z
28. Letzler R, Janoska-Bedi S, Penner A. Marching into the Leadership Pipeline: Gender, College Type, and ROTC Participation. Socius. 2025;11. doi:10.1177/23780231241297776
29. Riebe D, Franklin B, Thompson P, et al. Updating ACSM’s Recommendations for Exercise Preparticipation Health Screening. Med Sci Sports Exerc. 2015;47(11):2473-2479. doi:10.1249/MSS.0000000000000664
30. Damoun N, Amekran Y, Taiek N, El Hangouche AJ. Heart rate variability measurement and influencing factors: Towards the standardization of methodology. Glob Cardiol Sci Pract. HBKU Press. 2024;2024(4). doi:10.21542/gcsp.2024.35
31. Warburton DER, Jamnik VK, Bredin SSD, Gledhill N. The Physical Activity Readiness Questionnaire for Everyone (PAR-Q+) and electronic Physical Activity Readiness Medical Examination (ePARmed-X+). Health & Fitness Journal CSEP Health & Fitness Program of BC. 2011;4(2). doi:10.14288/hfjc.v4i2.103
32. Ozemek Cemal, Bonikowske AR., Christle JW., Gallo PM. ACSM’s Guidelines for Exercise Testing and Prescription. 11th ed. Wolters Kluwer; 2025.
33. Lohman TG, Roche AF, Martorell R. Anthropometric Standardization Reference Manual. Human Kinetics Books; 1988.
34. Gilgen-Ammann R, Schweizer T, Wyss T. RR interval signal quality of a heart rate monitor and an ECG Holter at rest and during exercise. Eur J Appl Physiol. 2019;119(7):1525-1532. doi:10.1007/s00421-019-04142-5
35. Krummenacher M, Tarvainen M, Montet E, Turner MC, Guseva Canu I. Which Device Is Most Suitable for Measuring Heart Rate Variability in the Field? A Comparative Evaluation of Two Leading Options. J Occup Environ Med. 2025;67(9):717-722. doi:10.1097/JOM.0000000000003479
36. Scafoglieri A, Clarys JP. Dual energy X-ray absorptiometry: gold standard for muscle mass? J Cachexia Sarcopenia Muscle. 2018;9(4):786-787. doi:10.1002/jcsm.12308
37. Lewiecki EM, Binkley N, Morgan SL, et al. Best Practices for Dual-Energy X-ray Absorptiometry Measurement and Reporting: International Society for Clinical Densitometry Guidance. Journal of Clinical Densitometry. 2016;19(2):127-140. doi:10.1016/j.jocd.2016.03.003
38. Nana A, Slater GJ, Stewart AD, Burke LM. Methodology Review: Using Dual-Energy X-Ray Absorptiometry (DXA) for the Assessment of Body Composition in Athletes and Active People. Int J Sport Nutr Exerc Metab. 2015;25(2):198-215. doi:10.1123/ijsnem.2013-0228
39. Gabani V, Murugan S. Reliability and Validity of Kubios HRV Smart Phone Application as Measures of Heart Rate Variability. Int J Curr Res Rev. 2024;16(06):07-10. doi:10.31782/ijcrr.2024.16602
40. Schaffarczyk M, Rogers B, Reer R, Gronwald T. Validity of the Polar H10 Sensor for Heart Rate Variability Analysis during Resting State and Incremental Exercise in Recreational Men and Women. Sensors. 2022;22(17):6536. doi:10.3390/s22176536
41. Kasap M, Aydin GR. Box breathing or six breaths per minute: Which strategy improves athletes post-HIIT cardiovascular recovery? PLoS One. 2025;20(11 November). doi:10.1371/journal.pone.0336615
42. Turnes T, Possamai LT, Penteado dos Santos R, de Aguiar RA, Ribeiro G, Caputo F. Mechanical power during an incremental test can be estimated from 2000-m rowing ergometer performance. J Sports Med Phys Fitness. 2020;60(2). doi:10.23736/S0022-4707.19.09967-5
43. Gao WD, Nuuttila OP, Fang HB, Chen Q, Chen X. A New Fitness Test of Estimating VO2max in Well-Trained Rowing Athletes. Front Physiol. 2021;12. doi:10.3389/fphys.2021.701541
44. Penichet-Tomas A, Jimenez-Olmedo JM, Pueo B, Olaya-Cuartero J. Physiological and Mechanical Responses to a Graded Exercise Test in Traditional Rowing. Int J Environ Res Public Health. 2023;20(4). doi:10.3390/ijerph20043664
45. Shariat A, Cleland JA, Danaee M, et al. Borg CR-10 scale as a new approach to monitoring office exercise training. Work. 2018;60(4):549-554. doi:10.3233/WOR-182762
46. Montoye AHK, Vondrasek JD, Hancock Ii JB. Validity and Reliability of the VO2 Master Pro for Oxygen Consumption and Ventilation Assessment. Vol 13. 2020. http://www.intjexersci.com
47. Goldberger JJ, Arora R, Buckley U, Shivkumar K. Autonomic Nervous System Dysfunction: JACC Focus Seminar. J Am Coll Cardiol. Elsevier USA. 2019;73(10):1189-1206. doi:10.1016/j.jacc.2018.12.064
48. Buchheit M, Gindre C. Cardiac parasympathetic regulation: respective associations with cardiorespiratory fitness and training load. American Journal of Physiology-Heart and Circulatory Physiology. 2006;291(1):H451-H458. doi:10.1152/ajpheart.00008.2006
49. Plews DJ, Laursen PB, Stanley J, Kilding AE, Buchheit M. Training Adaptation and Heart Rate Variability in Elite Endurance Athletes: Opening the Door to Effective Monitoring. Sports Medicine. 2013;43(9):773-781. doi:10.1007/s40279-013-0071-8
50. Rogers B, Schaffarczyk M, Gronwald T. Estimation of Respiratory Frequency in Women and Men by Kubios HRV Software Using the Polar H10 or Movesense Medical ECG Sensor during an Exercise Ramp. Sensors. 2022;22(19):7156. doi:10.3390/s22197156
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Mar 20, 2026
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Parasympathetic Reactivation Following Maximal Exercise: Influence of Breathwork and Body Composition in ROTC Cadets: Original Research. (2026). Journal of Exercise and Nutrition, 9(1). https://doi.org/10.53520/jen2026.103232
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Copyright, 2026 by the authors. This work is licensed under the Creative Commons Attribution 4.0 International License.
How to Cite
Parasympathetic Reactivation Following Maximal Exercise: Influence of Breathwork and Body Composition in ROTC Cadets: Original Research. (2026). Journal of Exercise and Nutrition, 9(1). https://doi.org/10.53520/jen2026.103232