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IntroductionWe assessed metabolic and hormonal responses to high-load resistance exercise under varying normobaric hypoxia conditions with a saturation clamp.MethodsEmploying a counterbalanced, crossover test design, ten well-trained men participated in three exercise trials with normoxic or hypoxic gas mixtures to maintain arterial oxygen saturation at −90% and 80% [moderate (MH) and severe (SH) hypoxia, respectively]. The resistance exercise regimen comprised five sets of 10 repetitions of barbell back squats at 70% of one repetition maximum, with 1-min rest between sets. Metabolic and hormonal responses were measured before normoxia or hypoxia exposures (Pre 1), 15 min after the exposures (Pre 2), and at 0-, 15-, and 30-min post-exercises (T0, T15, and T30, respectively).ResultsCompared to Pre 2, blood lactate concentrations and growth hormone values were elevated at T0, T15, and T30 (p ≤ 0.001), while testosterone values increased at T0 in all conditions (p ≤ 0.009). Epinephrine values increased significantly from Pre 2 to T0 in SH only (p < 0.001). SH had significantly higher blood lactate concentrations (p = 0.023), growth hormone (p = 0.050), and epinephrine (p = 0.020) values at T30 compared to NM. Cortisol values were elevated above Pre 2 at T15 in MH and SH, while lower testosterone values were noted at T0 and T15 for SH compared to NM and MH (all p ≤ 0.05).DiscussionSevere simulated hypoxia, achieved through a saturation clamp during barbell back squats, may enhance metabolic and hormonal responses, particularly 30 min post-session. Nevertheless, the acute effects of hypoxia exposure seem to be overridden by the impact of high-load resistance exercise.

Background/Objectives: The athletic performance in badminton players largely depends on the capability of dynamic postural control to quickly restore balance when performing high-paced movements (e.g., frequent single-leg jumps). Our aim was to examine the effects of a novel intervention that combines balance training on an unstable surface and plyometric training on the performance of restoring balance after jumping, as well as related postural control in elite badminton players. Methods: Sixteen elite male badminton players were randomly allocated to either a combined balance and plyometric training group (CT, n = 8) or a plyometric training group (PT, n = 8). The CT group participated in a six-week training program, which included three training sessions per week. Each session comprised 40 min of plyometric exercises and 20 min of balance training. The PT group underwent plyometric training using the identical protocol as that of the CT group. All participants underwent identical technical training in badminton throughout the duration of the study. At baseline and immediately after the intervention, participants completed a single-leg jumping test. The capacity to restore balance was evaluated using the time to stabilization (TTS) after landing; and the related center of pressure (COP) fluctuations were also recorded. The effect of intervention was examined by two-way repeated-measures of ANOVA. Results: The primary two-way repeated-measures ANOVA models showed no significant interactions between group and time on either the time to stability in the dominant leg (D-TTS) or the time to stability in the non-dominant leg (N-TTS) (p > 0.70). Significant main effects of time, group, and their interactions on dominant legs of the anterior-posterior displacement difference (D-COPAP) (time: p = 0.001; group: p = 0.001; interaction: p = 0.014), non-dominant legs of the anterior-posterior displacement difference (N-COPAP) (time: p

Objective: In this study, we examined the effects of pre-exercise H2 gas inhalation on physical fatigue (PF) and prefrontal cortex (PFC) activation during and after high-intensity cycling exercise.Methods: Twenty-four young men completed four study visits. On the first two visits, the maximum workload (Wmax) of cycling exercise of each participant was determined. On each of the other two visits, participants inhaled 20 min of either H2 gas or placebo gas after a baseline test of maximal voluntary isometric contraction (MVIC) of thigh. Then participants performed cycling exercise under their maximum workload. Ratings of perceived exertion (RPE), heart rate (HR) and the PFC activation by using functional near-infrared spectroscopy (fNIRS) was measured throughout cycling exercise. The MVIC was measured again after the cycling.Results: It was observed that compared to control, after inhaling H2 gas, participants had significantly lower RPE at each workload phase (p < 0.032) and lower HR at 50% Wmax, 75% Wmax, and 100% Wmax during cycling exercise (p < 0.037); the PFC activation was also significantly increased at 75 and 100% Wmax (p < 0.011). Moreover, the H2-induced changes in PF were significantly associated with that in PFC activation, that is, those who had higher PFC activation had lower RPE at 75% Wmax (p = 0.010) and lower HR at 100% Wmax (p = 0.016), respectively.Conclusion: This study demonstrated that pre-exercise inhalation of H2 gas can alleviate PF, potentially by maintaining high PFC activation during high-intensity exercise in healthy young adults.