Effects of 10 weeks of military training on neuromuscular function in non-overreached and overreached conscripts

Abstract

The purpose of the study was to examine how military training influences neuromuscular function in non-overreached and overreached conscripts. A total of 24 male conscripts participated in the study (8 weeks basic training+2 weeks specialized training). All measurements were conducted during weeks 1, 5, 8 and 10. After the training period, nonoverreached (NOR, n= 16) and overreached (OR, n= 8) groups were compared. Isometric maximal forces (bench press, elbow flexion and knee extension), single twitch (plantar flexors), H-reflex, M-wave (Hmax/Mmax) and V-wave (V/Mmax) (soleus) were measured.In knee extension, force production increased in NOR by 22.5±20.5% (p<0.01) between weeks 1 and 8, which was not observed in OR (-1.1±18.2%, p>0.05). In OR, plantarflexion twitch contraction time increased between weeks 5 and 10 82.2±34.4% (p<0.01), which was not observed in NOR. No changes were observed in the H-reflex and V-wave responses in either of the groups. In conclusion, short term overreaching can also reduce the performance of the neuromuscular system, however, it seems to be more muscle than neural based. To avoid overreaching, more individualized periodization should be used during basic training.To enhance neuromuscular performance, maximal and explosive strength training should also be added into the basic training program.

Sleep of recruits throughout basic military training and its relationships with stress, recovery, and fatigue

“…Recovery strategies (e.g., physical rest, increased sleep) can help to counter some of the effects of sleep loss, stress and fatigue induced by BMT (Caravalho 2015 ), however, optimal recovery requirements are often highly individual (Kellmann et al 2018 ). Poor recovery practice can contribute to overtraining, reduced performance capacity, and injury (Kellmann et al 2018 ), all of which are noted outcomes during BMT (Booth et al 2006 ; Piirainen et al 2019 ). Whether an individual feels that sufficient recovery has occurred could be valuable when contextualising the current stress and fatigue state.…”

Training Load Monitoring and Injury Prevention in Military Recruits: Considerations for Preparing Soldiers to Fight Sustainably

“…Large increases in training load may precede injury (24,26) (51). Collectively, these strategies may reduce the risk of nonfunctional overreaching or overtraining (24,41).…”

Effects of intensified training with insufficient recovery on joint level and single muscle fibre mechanical function: The role of myofibrillar Ca2+sensitivity

“…Training adaptations are the result of acutely stressing physiological systems by manipulating the duration, frequency, and/or intensity of exercise (14, 15). However, when an increase in training load (i.e., intensified training) is not followed by adequate recovery, the benefits of exercise for both sport performance and overall health may be reduced (22, 26, 32, 38). While the effects of intensified training with insufficient recovery on the neuromuscular system are thought to play a role in the acute impairment of sport-specific tasks (6, 12), the underlying mechanisms are poorly characterized (8).…”

“…Strength can be assessed by performing an isometric maximum voluntary contraction (MVC), which is commonly used to measure changes in neuromuscular performance after a period of intensified training (6, 32). However, MVC force has previously been shown to not decrease following intensified training with insufficient recovery in both team sport athletes (6) and military conscripts (32).…”