Context: Cold-water immersion (CWI) has been applied widely as a recovery method, but little evidence is available to support its effectiveness.Objective: To investigate the effects of CWI on muscle damage, perceived muscle soreness, and muscle power recovery of the upper and lower limbs after jiu-jitsu training.Design: Crossover study. Setting: Laboratory and field. Patients or Other Participants: A total of 8 highly trained male athletes (age ¼ 24.0 6 3.6 years, mass ¼ 78.4 6 2.4 kg, percentage of body fat ¼ 13.1% 6 3.6%) completed all study phases.Intervention(s): We randomly selected half of the sample for recovery using CWI (6.08C 6 0.58C) for 19 minutes; the other participants were allocated to the control condition (passive recovery). Treatments were reversed in the second session (after 1 week).Main Outcome Measure(s): We measured serum levels of creatine phosphokinase, lactate dehydrogenase (LDH), aspartate aminotransferase, and alanine aminotransferase enzymes; perceived muscle soreness; and recovery through visual analogue scales and muscle power of the upper and lower limbs at pretraining, postrecovery, 24 hours, and 48 hours.Results: Athletes who underwent CWI showed better posttraining recovery measures because circulating LDH levels were lower at 24 hours postrecovery in the CWI condition (441.9 6 81.4 IU/L) than in the control condition (493.6 6 97.4 IU/L; P ¼ .03). Estimated muscle power was higher in the CWI than in the control condition for both upper limbs (757.9 6 125.1 W versus 695.9 6 56.1 W) and lower limbs (53.7 6 3.7 cm versus 35.5 6 8.2 cm; both P values ¼ .001). In addition, we observed less perceived muscle soreness (1.5 6 1.1 arbitrary units [au] versus 3.1 6 1.0 au; P ¼ .004) and higher perceived recovery (8.8 6 1.9 au versus 6.9 6 1.7 au; P ¼ .005) in the CWI than in the control condition at 24 hours postrecovery.Conclusions: Use of CWI can be beneficial to jiu-jitsu athletes because it reduces circulating LDH levels, results in less perceived muscle soreness, and helps muscle power recovery at 24 hours postrecovery.Key Words: creatine kinase, cryotherapy, L-lactate dehydrogenase, martial arts, muscle power Key PointsCold-water immersion may be beneficial to jiu-jitsu athletes because it decreased markers of muscle damage. Cold-water immersion reduced the perception of muscle pain. Cold-water immersion assisted in the recovery of the upper and lower limbs. Jiu-jitsu athletes could use cold-water immersion to improve performance and physiologic status, especially during training phases in which more intensive sessions are conducted and at the beginning of the season.

Background: The relationship between training and competition is very important and aims at a more specific and adequate preparation in Jiu-Jitsu. Problem and objective: To evaluate the relationship between training and competition through indications of injury and muscle strength. Methods: The study sample included nine subjects (22.54 ± 2.77 years of age) who were submitted to the following two conditions: 1) training simulation and 2) competition simulation. Results: There were no significant differences in the countermovement jump (CMJ) test. However, 48 hours after training there was an indication of values higher than the post-competition ones. Creatine kinase (CK) indicated significant differences in muscle damage after competition in relation to the other conditions and moments (p <0.01) with a high effect. Lactate dehydrogenase (LDH) showed differences in the moments before, during, and after both competition and training conditions (p <0.05) with a high effect. The power of the upper limbs (PUL) showed a medium correlation at 24h (> 0.55) and 48h (0.47) after the intervention. There was high correlation (> 0.70) for all conditions in the squat jump (SJ). LDH showed a high correlation (> 0.70) at 48 hours. Conclusion: There was a good correlation between training and competition simulation, which tends to indicate that the training model used in the study properly prepare Jiu-Jitsu athletes for the demands of competition. Level of evidence I; High-quality randomized clinical trial with or without a statistically significant difference, but with narrow confidence intervals.