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Objective: To test the effects of hot-water immersion on the rapid force production and parameters of neuromuscular function in healthy adults. Design: Cross-sectional study. Methods: Fifteen healthy adults (24.9 ± 5.6 years; 178 ± 11.4 cm; 72.8 ± 16.2 kg) performed neuromuscular assessments before, after and ∼15 min after either 90 min of 42 • C (hot) or 36 • C (sham-condition) water immersion (lower body). Knee extensors rate of torque development (RTD) was measured during explosive voluntary contraction in the interval of 0−50 ms (RTD V50 ) and 0−150 ms (RTD V150 ) and during electrically-evoked contractions by single twitches (RTD twitch ) and low-and high-frequencies doublets (RTD 20Hz and 100Hz ). Rate of EMG rise (RER) was calculated for voluntary contractions and half-relaxation time (HRT) and electromechanical delay (EMD) was measured during single twitches. Results: After the hot-water immersion (when rectal and muscle temperature were elevated [↑1 • C and ↑2.4 • C, respectively]), RTD V50 , RTD 20Hz and RTD 100Hz significantly increased and HRT decreased when compared to baseline and sham-condition (p < 0.05). Approximately 15 min after the hot-water immersion (when muscle temperature was still higher [↑1.4 • C], but rectal temperature at baseline level), RTD V50 remained higher and RTD twitch presented higher values than baseline and sham-condition. The RTD 20Hz and RTD 100Hz showed further increases compared to post hot-water immersion trials. HRT showed no changes compared to post water immersion, but the EMD presented lower values than baseline and sham-condition. No changes were observed for RTD V150 and RER at any moment. Conclusion: Increased muscle temperature provoked by 42 • C hot-water immersion increases the early phase of the RTD (<70 ms) (voluntary and evoked) and decreases HRT and EMD of the knee extensors.

Information about the Vietnamese physical education (PE) programme is limited due to a lack of relevant studies. Using the Health Optimising Physical Education as a conceptual framework, this study examined students’ physical activity (PA) levels in the fifth-grade PE programme in Vietnam and barriers to programme implementation. Eight schools (28 PE classes) were randomly selected for assessing students’ PA levels, lesson context, and PA promotion during PE lessons using the System for Observing Fitness Instruction Time. In-depth interviews were also conducted with school administrators, PE instructors, and classroom teachers using semi-structured guides to examine barriers influencing the implementation of the current PE programme. Results showed students spent 33% of PE time in moderate–vigorous physical activity (MVPA), which is less than the international recommendation of 50%. The amount of MVPA varied by school type, instructor gender and qualification. Programme implementation was negatively affected by the current structure that limits autonomy, a proclivity for a “one size fits all” approach to teaching PE, and limited motivation for PE instructors to improve their teaching. The low perceived value of PE, lack of support and professional development for existing PE instructors, and an over-emphasis on sports training due to available financial incentives were also identified as important barriers that affected programme implementation. Addressing these barriers could help improve the quality of the Vietnamese PE programme.

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DOI: http://dx.doi.org/10.5007/1980-0037.2016v18n3p322 The purpose of the present investigation was to identify the effects of a 130-km cycling race on indices of biochemical indirect markers of muscle damage and muscle soreness responses during a 72-hour recovery period. Fifteen endurance-trained male cyclists which were competing for more than 2 years and were involved in systematic training at least of 3 days/wk underwent a collection of indirect biochemical markers of muscle damage (CK, LDH, Myo) and delayed onset of muscle soreness (DOMS), at five different moments of data collection: before (PRE) and immediately after (POST) a 130-km cycling race, and 24, 48, 72 hours following the cycling race. CK and LDH plasma concentrations significantly increased POST-race (p < 0.001) and remained high throughout the 72 hour recover period (CK: p < 0.05; LDH: p < 0.001). Myo increased significantly POST-race (p < 0.001) and returned to the PRE-race values 24 hours thereafter (p < 0.05). DOMS increased significantly POST-race (p < 0.001) and returned to the PRE-race values at 48 hours after (p > 0.05). A 130-km cycling race has a noteworty effect on indices of biochemical indirect markers of muscle damage and muscle soreness responses, indicating that 72 hour recovery period do not seems to be enough for long-distance cyclist, and reinforce the propositions of scientific literature about the need of a sufficient recovery period for cycling endurance athletes.