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Study aim: The purpose of this study was to evaluate neuromuscular adaptations in conscripts with different fitness levels (VO2max) during 8 weeks of military basic training (BT).

Study aim: The aim of this study was to evaluate the effects of training while wearing socks differing in compression level (clinical, sub-clinical, regular) on performance of static and dynamic balancing and agility tasks in healthy, physically active people. We sought to understand whether socks with different compression properties supported postural regulation and agility task performance by enhancing somatosensory perception, unskewed by specific age range effects. Material and methods: Participants comprised 61 adults aged 18-75 years, divided into three groups (two experimental groups wearing clinical or sub-clinical level compression socks, and one control group wearing regular non-compression socks during training). An 8-week (2 × 1h per week) intervention programme was administered to train static and dynamic balance and postural control, leg strength and agility. Results: A mixed model ANOVA revealed no differences in static and dynamic balance and postural control and agility performance between clinical, sub-clinical, and control groups before and after training. All groups significantly improved their test performance, suggesting that training had some benefit on motor performance. Conclusions: These results raised interesting questions requiring further investigation to examine the effects of wearing socks (with and without different levels of compression) on motor behaviours in specific groups of elderly vs. young participants, in physically active vs. less physically active people, and in performance settings outside standardized laboratory tests to study applications in natural performance environments.

Following ankle movement, posterior balance perturbation evokes short-(SLR ~30-50 ms), medium- (MLR ~50-60 ms), and long-latency responses (LLR ~70-90 ms) in soleus muscle before voluntary muscle contraction. Transcranial magnetic stimulation (TMS) and Hoffmannreflex (H-reflex) measurements can provide insight into the contributions of corticospinal and spinal mechanisms to each response. Motor evoked potential (MEP) and H-reflex responses have shown good reliability in some dynamic muscle contraction tasks. However, it is still unclear how reliable these methods are in dynamic balance perturbation and corticospinalmodulation during long amplitude balance perturbation tasks. 14 subjects completed two test sessions in this study to evaluate the reliability of MEPs, H-reflex, and corticospinal modulation during balance perturbation. In each session, the balance perturbation system operated at 0.25 m/s, accelerating at 2.5 m/s² over 0.3 m displacement. MEPs and H-reflexes were elicited in the right leg soleus muscle at four delays after ankle movement (10 ms, 40 ms, 80 ms, and 140 ms), respectively. Test-retest reliability of MEP and H-reflex amplitudes were assessed via intraclass correlation coefficients (ICC) both between- and within-session. Between-session test-retest reliability for MEPs was excellent (ICC = 0.928-0.947), while H-reflex demonstrated moderate-to-good reliability (ICC = 0.626-0.887). Within session reliability for both MEPs and H-reflex was excellent (ICC = 0.927-0.983). TMS and H-reflex measurements were reliable at different delays after perturbation between- and within-sessions, which indicated that these methods can be used to measure corticospinal excitability during balance perturbation. [ABSTRACT FROM AUTHOR]

The dropout rate in the Finnish military service has increased during the past two decades. At the same time, the physical fitness level of young Finnish males has decreased, possibly leading to overtraining in new conscripts. The purpose of the present study was to examine whether body composition would influence neuromuscular function during the 8-week basic training (BT) period. Eighteen healthy male subjects (19 [+ or -] 1 years) were divided into three different groups according to their body fat %. Group 1 (< 10%), group 2 (10-13%) and group 3 (>13%). The soleus H-reflex response was measured in the standing position. In the seated position (knee 160[degrees] and hip 110[degrees]), the V-wave response was measured during maximal voluntary contraction, and the single twitch response was measured in passive conditions. In body composition (fat-free mass and fat mass) was observed small but not significant changes during 8-week period. H-reflex activity increased in groups 2 (10.9% not significant [ns]) and 3 (2.8% ns) but decreased in group 1 (-34.8%, p < 0.05) during the 8-week period. V-wave values decreased in all groups, and the biggest decrement was observed in group 2 (-34.7%, p < 0.05), whereas in group 1 and group 3 no significance was observed. For each group the single twitch torque (G1 ns, G2 and G3 p < 0.05) increased during the 8-week period. The major finding of the study was that the BT period did not cause overtraining in conscripts. Increased activity of the H-reflex and single twitch torque supports this finding. V-wave activity was decreased in all groups, which may also indicate that the training did not stimulate neural activity. In general, the observed changes in neuromuscular system supports the main finding. KEY WORDS neuromuscular fatigue, overtraining, H-reflex

The purpose of this study was to examine whether split step (small hop before step) would be more beneficial than no-split condition in simulated tennis response situation. In addition, it was studied if movement time of the response is related to separately measured force production capabilities and reflex sensitivity of the players. Nine skilled male tennis players participated in this study. Subjects stood on a force plate and reacted to a light signal and moved to appointed direction as fast as possible. With split step the participants were 13.1% faster (P <0.05) than without split step from the start to the distal end of the so called close range movement continuum (2.70 m). This was mainly explained by 43.6% faster time (P <0.05) from the signal to the onset of force production. Greater vertical forces were observed with split step: 15.7% greater F(z) mean force (P <0.05), 60.0% greater F(z) peak force (P<0.01). In split step both mean (r= − 0.813, P <0.01) and peak (r=−0.765, P <0.05) vertical forces (Fz) correlated negatively with the time from the onset of the force production to the photocell. With split step higher EMGs were observed in muscles responsible for ankle joint movement indicating that different strategies were used. Due to the split step the players were able to start the movement faster which mostly explains the advantages over the no-split step condition. Split step condition may also benefit from stretch shortening type of muscle action. [ABSTRACT FROM AUTHOR]

The article presents a study which examined the effects of body composition on the neuromuscular function of Finnish draftees during basic training. Small, insignificant changes to body composition were noticed in test subjects during their eight-week basic training period. The author focuses on instances of neuromuscular fatigue.