Functional overstrain during long-term rehabilitation of military personnel with musculoskeletal Injuries of the limbs

Andrii Chernozub; Oleh Olkhovyi; Lesia Korobeinikova; Alina Kizilova; Oleksandr Zavizion; Andrii Maidachenko

doi:10.15391/prrht.2025-10(5).04

Authors

Andrii Chernozub Department of Sports Theory and Physical Education, Lesya Ukrainka Volyn National University, Lutsk, Ukraine https://orcid.org/0000-0001-6293-8422
Oleh Olkhovyi Department of Theory and Methods of Physical Education, Kharkiv State Academy of Physical Culture, Kharkiv, Ukraine https://orcid.org/0000-0002-5223-5229
Lesia Korobeinikova Department of Combat Sports and Strength Sports, National University of Ukraine on Physical Education and Sport, Ukraine https://orcid.org/0000-0001-8648-316X
Alina Kizilova Department of Sports Theory and Physical Education, Lesya Ukrainka Volyn National University, Lutsk, Ukraine https://orcid.org/0000-0002-2475-7054
Oleksandr Zavizion Department of Sports Theory and Physical Education, Lesya Ukrainka Volyn National University, Lutsk, Ukraine https://orcid.org/0009-0007-3806-7234
Andrii Maidachenko Department of Sports Theory and Physical Education, Lesya Ukrainka Volyn National University, Lutsk, Ukraine https://orcid.org/0009-0009-1094-9248

DOI:

https://doi.org/10.15391/prrht.2025-10(5).04

Keywords:

servicemen, musculoskeletal injuries of the limbs, functional overstrain, long-term rehabilitation, readaptation, biomarkers

Abstract

Purpose. To study the main causes of functional overstrain in military personnel with musculoskeletal injuries of the limbs during long-term rehabilitation while applying standard physical therapy protocols.

Material & Methods. 56 military personnel who had sustained musculoskeletal injuries of the limbs 16 months earlier as a result of mine-explosive and gunshot wounds were examined. During the previous 10 months of long-term rehabilitation, standard physical therapy protocols were used according to the specific nosology. The participants were divided into groups and subgroups according to their nosology and type of heart rhythm regulation. Test load 1 was developed for servicemen with upper limb injuries, and test load 2 – for military personnel with lower limb injuries. To assess the adaptive and compensatory responses of the participants to the test loads, indicators of heart rate spectral analysis and blood biomarkers (creatine phosphokinase, lactate dehydrogenase, testosterone, and cortisol) were used. Monitoring of possible adaptive changes was carried out before and after 15 days of using physical therapy protocols under the supervision of rehabilitation specialists.

Results. At the beginning of the study, regardless of the nosology, a shift in autonomic balance was simultaneously observed toward both sympathetic and parasympathetic activity. In 50% of the examined participants, an enhancement of the central contour of sinus rhythm regulation was observed along with decreased cortisol concentration and increased LDH activity in the blood. Such adaptive-compensatory responses to a stress stimulus indicate low muscle glycogen reserves and an insufficient level of resistance, reflecting a state of non-functional overstrain and a risk of adaptive failure. Other study participants had a decrease in the influence of the central contour, accompanied by opposite changes in the LF/HF ratio. CPK levels increased significantly, and blood cortisol concentration almost reached the upper limit of normal, indicating a state of functional overstrain. The results obtained after 15 days of using the prescribed physical therapy protocols under the supervision of rehabilitation specialists showed almost identical changes in HRV indicators and blood biomarkers as those observed at the beginning of the study. Such prolonged changes in biomarkers indicate a continuously progressing depletion of adaptive reserves due to compensatory reactions triggered by excessive stress stimuli.

Conclusions. Using inpatient rehabilitation services by military personnel over the previous 10 months led to the development of a state of non-functional overstrain in 50% of the examined individuals. A re-examination conducted over 15 days in inpatient conditions, concerning the influence of physical therapy protocols recommended by physical rehabilitation specialists on the neuromuscular system readaptation, confirmed the previous results.

The study results allowed for a clear identification of the main problems causing the FOR and NFOR state development in military personnel with these nosologies, and the necessity of using a wide range of biomarkers to assess their adaptive and compensatory responses to physical load.

References

Busso, T., & Chalencon, S. (2025). Differentiating acute fatigue and overreaching during intensified training using a recursive least squares algorithm combined with the variable dose-response model. Eur J Appl Physiol, 125(5), 1437-1448. https://doi.org/10.1007/s00421-024-05692-z

Cadegiani, F., & Kater, C. (2019). Basal Hormones and Biochemical Markers as Predictors of Overtraining Syndrome in Male Athletes: The EROS-BASAL Study. J Athl Train, 54(8), 906-914. https://doi.org/10.4085/1062-6050-148-18

Chernozub, A., Manolachi, V., Potop, V., Khudyi, O., Kozin, S., Bokatuieva, V., Kizilova, A., Stanescu, M., & Timnea, C. (2023). Kinesiological models of the neuromuscular system readaptation in mature women after prolonged hypokinesia. Health, Sport, Rehabilitation, 9(1), 78-92. https://doi.org/10.34142/HSR.2023.09.01.07

Chernozub, A., Tsos, A., Olkhovyi, O., Ikkert, O., Koval, V., & Kirychuk, Y. (2024). Comparative study of adaptive reserves of servicemen and servicemen-athletes with neuromuscular injuries after the post-acute rehabilitation. Physical rehabilitation and recreational health technologies. 9(6), 468-475. https://doi.org/10.15391/prrht.2024-9(6).02

Chernozub, A., Tsos, A., Olkhovyi, O., Hlukhov, I., Koval, V., & Zavizion, O. (2025). Readaptation of functional capabilities of special unit servicemen with long-term hypodynamia caused by peripheral neuromuscular system damage. Physical rehabilitation and recreational health technologies, 10(1), 9-19. https://doi.org/10.15391/prrht.2024-9(6).02

Fiala, O., Hanzlova, M., Borska, L., Fiala, Z., & Holmannova, D. (2025). Beyond physical exhaustion: Understanding overtraining syndrome through the lens of molecular mechanisms and clinical manifestation. Sports Med Health Sci, 7(4), 237-248. https://doi.org/10.1016/j.smhs.2025.01.006

Grandou, C., Wallace, L., Coutts, A., Bell, L., & Impellizzeri, F. (2021). Symptoms of Overtraining in Resistance Exercise: International Cross-Sectional Survey. Int J Sports Physiol Perform, 16(1), 80-89. https://doi.org/10.1123/ijspp.2019-0825

Gancitano, G., Baldassarre, A., Lecca, L., Mucci, N., Petranelli, M., Nicolia, M., Brancazio, A., Tessarolo, A., & Arcangeli, G. (2021). HRV in Active-Duty Special Forces and Public Order Military Personnel. Sustainability,13(7), 1-15. https://doi.org/10.3390/su13073867

Gray, L., Coppack, R., Barker-Davies, R., Cassidy, R., Bennett, A., & Caplan, N. (2025). Efficacy and acceptability of different blood flow restriction training interventions during the rehabilitation of military personnel with lower limb musculoskeletal injuries: protocol for a two-phase randomised controlled trial. BMJ Open, 15(5), e096643. https://doi.org/10.1136/bmjopen-2024-096643

Gregg, B., Barrow, T., Heffernan, C., & Julian, C. (2025). Characterization of Direct Access Upper Extremity Rehabilitation Services by Military Occupational Therapists. Mil Med, 190 (2), 574-580. https://doi.org/10.1093/milmed/usaf276

Korobeinikova, L., Raab, M., Korobeynikov, G., Pryimakov, O., Kerimov, F., Chernozub, A., Korobeinikova, I., & Goncharova, O. (2024) Comparative analysis of psychophysiological state among in physical active and sedentary persons. Journal of Physical Education and Sport, 24 (2) ,382-389. https://doi.org/10.7752/jpes.2024.02046

Lodhi, M., Brismée, J., Shapiro, R., LeClere, L., & Waltz, R. (2025). Impact of Functional Training on Injuries After Anterior Cruciate Ligament Reconstruction for Return-to-Duty Status in U.S. Naval Academy Midshipmen: A Retrospective Analysis. Mil Med, 190(7-8), e1595-e1600. https://doi.org/10.1093/milmed/usae572

Maqsood, R., Schofield, S., Bennett, A., Khattab, A., Bull, A., Fear, N., Cullinan, P., & Boos, C. (2025). Long-term impact of combat-related traumatic injury on heart rate variability: findings from the ADVANCE study. BMJ Mil Health, e002895. https://doi.org/10.1136/military-2024-002895

Mallardo, M., Daniele, A., Musumeci, G., & Nigro, E. (2024). A Narrative Review on Adipose Tissue and Overtraining: Shedding Light on the Interplay among Adipokines, Exercise and Overtraining. Int J Mol Sci, 25(7), 4089. https://doi.org/10.3390/ijms25074089

Miyatsu ,T., Smith, B., Koutnik, A., Pirolli, P., & Broderick, T. (2023). Resting-state heart rate variability after stressful events as a measure of stress tolerance among elite performers. Front Physiol, 13, 1070285. https://doi.org/10.3389/fphys.2022.1070285

Olkhovyi, O., Tykhorskyi, O., Didyuk, N., Savchenko, V., Babenko, S., Romanenko, V., & Potop, V. (2025). Effect of pre-competition weight loss on onautonomic regulation and functional state qualified powerlifters. Slobozhanskyi Herald of Science and Sport, 29(2), 184-192. https://doi.org/10.15391/snsv.2025-2.09

Potop, V., Mihailescu, L., Mahaila, I., Zawadka-Kunikowska, M., Jagiello, W., Chernozub, A., Baican, S., Timnea, C., Ene-Voiculescu, C., & Ascinte, A. (2024). Applied biomechanics within the Kinesiology discipline in higher education. Physical Education of Students, 28(2), 106-19. https://doi.org/10.15561/20755279.2024.0208

Salonen, M., Huovinen, J., Kyröläinen, H., Piirainen, J., & Vaara, J. (2019). Neuromuscular Performance and Hormonal Profile During Military Training and Subsequent Recovery Period. Mil Med, 184(3-4), e113-e119. https://doi.org/10.1093/milmed/usy176

Spiering, B., Clark, B., Schoenfeld, B., Foulis, S., & Pasiakos, S. (2023). Maximizing Strength: The Stimuli and Mediators of Strength Gains and Their Application to Training and Rehabilitation. Journal of Strength and Conditioning Research, 37(4), 919-929. https://doi.org/10.1519/JSC.0000000000004390

Stephenson, M., Thompson, A., Merrigan, J., Stone, J., & Hagen, J. (2021). Applying Heart Rate Variability to Monitor Health and Performance in Tactical Personnel: A Narrative Review. Int J Environ Res Public Health, 18(15), 8143. https://doi.org/10.3390/ijerph18158143.

Uphill, A., Kendall, K., Baker, B., Guppy, S., Brown, H., Vacher, M., Nindl, B., & Haff, G. (2025). The physiological consequences of and recovery following the Australian Special Forces Selection Course. Appl Physiol Nutr Metab, 50, 1-13. https://doi.org/10.1139/apnm-2024-0117

Watanabe, D., & Wada, M. (2025). Cellular mechanisms underlying overreaching in skeletal muscle following excessive high-intensity interval training. Am J Physiol Cell Physiol, 328(3), C921-C938. https://doi.org/10.1152/ajpcell.00623.2024

Whitehurst, R., Romanello, A., Reilly, N., & Goss, D. (2025). U.S. Army Holistic Health and Fitness Programs Outperform Traditional Physical Therapy Models for Soldiers. Mil Med. usaf419. https://doi.org/10.1093/milmed/usaf419