Volume 12, Issue 2 (9-2026)                   J Sport Biomech 2026, 12(2): 286-300 | Back to browse issues page


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Omidi H, Sabzevari Rad R, Ghorbani M. Changes in Lower Limb Strength and Neuromuscular Control during One Year of Military Training in Officer Cadets. J Sport Biomech 2026; 12 (2) :286-300
URL: http://biomechanics.iauh.ac.ir/article-1-452-en.html
1- Department of Physical Education and Sport Sciences, Faculty of Command and management, Imam Ali Military' University, Tehran, Iran.
2- Department of Sport Injuries and Corrective Exercise, Faculty of Physical Education and Sport Sciences, University of Guilan, Rasht, Iran.
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Extended Abstract
1.    Introduction

Military readiness is among the most critical requirements of any country, as an army lacking adequate readiness cannot effectively defend its borders. Human resources play a central role in achieving this readiness; consequently, the assessment and development of physical fitness have long been shared priorities within armed forces (1). Enhanced physical fitness improves resilience to both physical and psychological stresses encountered in combat, enabling military personnel to perform operational tasks effectively and maintain optimal performance under demanding conditions (3,4). The development of physical characteristics such as strength, balance, and endurance is essential for improving the functional capacity and practical military skills of service members, thereby contributing to successful professional and combat operations (4). Previous studies have demonstrated that military training positively influences soldiers’ physical fitness. A systematic review reported that military training enhances physical fitness, operational readiness, and resilience in harsh environments (9). Additionally, military training has been shown to increase muscular strength (10), improve balance (11), and enhance resilience during operational tasks (12). Despite these findings, a notable challenge in the field of military physical fitness research is the limited attention paid to neuromuscular factors—particularly balance and proprioception—following military and athletic training (13). For example, Ghorbani et al. reported that military training may increase the risk of musculoskeletal injuries by inducing alterations in landing biomechanics, including muscular asymmetry and impaired proprioception (14).
Another important limitation of previous research is that, due to the time-consuming nature of longitudinal investigations, many studies have focused primarily on short-term training interventions lasting 6 to 8 weeks and examined outcomes such as strength, endurance, balance, and proprioception (17). Consequently, the comprehensive and real-world effects of long-term military training programs on these neuromuscular components remain insufficiently explored. Given that muscular strength, muscular endurance, and balance are fundamental pillars for effective performance in military duties and operations (4,18), targeted attention to these components within officer cadet training programs is essential. Therefore, the present study aimed to evaluate the direct and practical effects of a routine military training program by examining changes in lower-limb neuromuscular indices, with a particular focus on strength, balance, and proprioception.
2.    Methods
This study employed a longitudinal, prospective observational design with pre-test and post-test measurements. The statistical population consisted of officer cadets enrolled at Imam Ali University. Sample size was determined using G*Power software based on previous studies, assuming a significance level of 0.05 and a statistical power of 0.80, which yielded a required sample size of 30 participants (19). To account for potential attrition due to withdrawal or incomplete participation, 35 cadets were initially recruited. Ultimately, data from 30 participants who completed all assessments without significant attrition were included in the final analysis. Baseline data on selected muscle strength, dynamic balance, and lower-limb proprioception were collected upon the cadets’ entry to Imam Ali University. Following the pre-test assessments, participants completed a standard, routine military training program for a duration of one year. The training program comprised sprint and endurance running, field maneuvers involving rapid directional changes, obstacle jumping, load carriage (e.g., military backpacks), and bodyweight resistance exercises. After the one-year training period, all measurements were repeated using the same assessment protocols.
3.    Results
The results of the repeated measures analysis of variance in Table 1 showed that Y-balance in the anterior direction (η² = 0.18, P = 0.009) and posterolateral direction (η² = 0.20, P = 0.042) significantly improved in the post-test. Additionally, significant differences were observed between the dominant and non-dominant limbs in the posteromedial direction (P = 0.028), posterolateral direction (P = 0.006), and total score (P < 0.001 in the pre-test and P = 0.032 in the post-test). A significant interaction effect was observed only in the posterolateral direction (P = 0.048), indicating a greater improvement in the dominant limb compared to the non-dominant limb. 
4.    Discussion
The results of this study demonstrate the positive and significant impact of one year of military training on enhancing key neuromuscular performance indicators, including dynamic balance, proprioceptive accuracy, and muscular strength, in military cadets. The observed improvements, particularly in the dominant limb, highlight the importance of intensive and diverse military training in inducing superior neuromuscular adaptations. These findings can serve as a foundation for designing optimized training programs for military and athletic populations. 

Ethical Considerations
Compliance with ethical guidelines

This study was conducted in accordance with the 2013 Helsinki Declaration. Participants provided informed consent after being informed of the research objectives. Data confidentiality and the right to withdraw were upheld.
Funding
This research did not receive any financial support from government, private, or non-profit organizations. 
Authors' contributions
All authors contributed equally to preparing the article.
Conflicts of interest
The authors declare that they have no conflict of interest associated with this study. 
Type of Study: Research | Subject: Special
Received: 2025/10/8 | Accepted: 2026/01/21 | Published: 2026/01/31

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