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Purpose The aim of this investigation was to evaluate the effects of local cryotherapy on the recovery from symptoms of exercise-induced muscle damage (EIMD) on biceps brachii. Methods Nineteen untrained women performed an eccentric protocol of damage induction (2 sets of 10 repetitions) in both arms after the baseline data collection. The cryotherapy was applied for 20 min, twice per day, for 4 days following the eccentric exercise. Randomly, one of the subject's arms was assigned as intervention, and received cryotherapy, the opposite arm served as control. As muscle damage indirect markers, we collected muscle thickness, and echo intensity, delayed onset muscle soreness, and peak torque at baseline (PRE), and at 24, 48, 72, and 96 h. Results Muscle thickness at PRE was significantly lower than all time points in both experimental and control arms. Echo intensity at PRE was significantly lower than 24, 48, and 72 h in the experimental arm, and significantly lower than all time points in the control arm. Muscle soreness assessed by flexion-extension, and by self-palpation of both the experimental and the control arms significantly increased compared to the PRE value at 24, 48, and 72 h. Peak Torque of both experimental and control arm was significantly lower than all time points after EIMD. None of the muscle damage indirect markers showed any significant difference between arms at any moment (p [ 0.05).Conclusion The results demonstrated that the protocol of cryotherapy utilized in the present study was not effective in enhancing the recovery from EIMD in untrained women.

BACKGROUND: Stretching exercises increase the joint range of motion (ROM) and depend on the skeletal tissues' exposition-time to stretch. However, it is unclear how a long stretching time affects the muscle-tendon unit's passive mechanical properties. AIM: This study aimed to analyze changes in the triceps surae muscle-tendon unit’s passive mechanical properties before and after a 10-minute passive stretching protocol. METHOD: Thirty healthy participants (26.57 ± 3.82 years old) were allocated into a control group (n=15), who did not perform any intervention, and to an experimental group (n=15), who performed one bout of a 10-minute ankle plantar flexor passive static stretching. Ankle ROM, plantar flexor passive torque, and myotendinous junction displacement were evaluated pre-intervention, immediately after, and 15, 30, 45, and 60 minutes after the end of the intervention. The stiffnesses of the muscle-tendon unit, muscle, and tendon were calculated for all moments. A generalized estimating equation test was performed to compare groups and moments. RESULTS: The experimental group increased the ROM (p<0.001) from pre- to post-intervention and remained augmented up to 60 minutes. The myotendinous junction displacement decreased at post-30 and post-45 moments compared to pre-intervention. Muscular stiffness increased immediately after stretching and post-45 and post-60 minutes. Passive torque and musculotendinous unit stiffness decreased over time, with trivial, small, and moderate effect sizes, respectively. CONCLUSION: Passive static stretching (10 min) generates an acute ROM increase associated with muscle-tendon unit passive mechanical properties reduction, which lasts up to one-hour post-intervention.