Effect of Cold Water Immersion Performed on Successive Days on Physical Performance, Muscle Damage, and Inflammatory, Hormonal, and Oxidative Stress Markers in Volleyball Players.

de Freitas, VH, Ramos, SP, Bara-Filho, MG, Freitas, DGS, Coimbra, DR, Cecchini, R, Guarnier, FA, and Nakamura, FY. Effect of cold water immersion performed on successive days on physical performance, muscle damage, and inflammatory, hormonal, and oxidative stress markers in volleyball players. J Strength Cond Res 33(2): 502-513, 2019-The aim of this study was to investigate the effects of daily cold water immersion (CWI) on physical performance, muscle damage, and inflammatory, hormonal, and oxidative stress markers in volleyball. Six players were submitted to CWI and six players to a placebo, during 5 training days. Thigh circumference, squat jump, and agility were measured on the first, third, and sixth days. On the first and sixth days, blood and saliva were collected for analysis of oxidative stress, muscle damage, and inflammatory and hormonal levels. Muscle soreness and countermovement jump were quantified daily. The physical performance comparisons did not present differences and the only between group comparison with a large effect size (ES = -1.39) was in Δ% between day 1 and day 2 for countermovement jump. Delayed onset muscle soreness and creatine kinase increased in both groups and the ESs of between group comparisons of Δ% between moments were not more than moderate. Thigh circumference increased only in the placebo group (p = 0.04) and the ES of the between group comparisons of Δ% between moments was large (1.53). No differences were found in oxidative stress, or inflammatory markers. Cortisol decreased only in the CWI-group (p ≤ 0.05) and the ESs of the between group comparisons of Δ% between moments of the testosterone to cortisol ratio (-1.94) and insulin-like growth-1 (-1.34) were large. Despite the positive effects of daily CWI on muscle edema and hormonal status, the limited effects of CWI on performance, muscle damage, inflammation markers, and reactive oxygen species mediators signal the unimportance of the daily practice of this recovery method in volleyball players.

Seasonal Training Load Distribution of Professional Futsal Players: Effects on Physical Fitness, Muscle Damage and Hormonal Status.

The aims of the present study were to describe the training load (TL) distribution of a professional futsal team and verify its subsequent effects on physical performance, muscle damage, and hormonal status. Twelve male professional futsal players (24.3 ± 4.7 years old; 75.5 ± 7.7 kg; and 173.4 ± 4.5 cm) participated in this study. A training program of 22 weeks (6 weeks of pre-season and 16 weeks of in-season) was analyzed. The session rating of perceived exertion method was used to monitor TLs. Physical tests (PTs; countermovement jump (CMJ), 5- and 20-m sprint, T-test, and multistage 20-m shuttle-run tests) were performed 4 times throughout the season (PT1-PT4). Blood sample (BS) collection (Creatine kinase [CK], testosterone, and cortisol) was performed in 7 occasions (BS1-BS7). TLs were higher in pre-season compared to in-season (p < 0.001). Countermovement jumps (CMJs) and 5- and 20-m performances were better in PT3 (CMJ: 0/23/77, 5-m: 0/3/97, and 20-m: 0/1/99) and PT4 (CMJ: 0/8/92, 5- and 20-m: 0/0/100) than in PT1; T-test performance and V[Combining Dot Above]O2max was better in all moments compared with those of PT1 (0/0/100). Higher CK concentration (p = 0.03) and testosterone to cortisol (T:C) ratio values (p = 0.02) were detected in BS2 vs. BS1. An increase in C (p = 0.007) and a decrease in T:C ratio (p = 0.003) was observed from BS4 to BS5. The training program demonstrated higher TLs during the periods with low incidence of matches, emphasis on endurance and strength training during pre-season, speed and power training throughout in-season. This TL organization provides sufficient stimulus for appropriate physical fitness development in professional futsal players, without causing negative disturbances.

Sensitivity of the Yo-Yo Intermittent Recovery Test and cardiac autonomic responses to training in futsal players.

PURPOSE: This study examined the sensitivity of maximal (Yo-Yo Intermittent Recovery [IR] 1 and 2) and submaximal (5'-5') tests to identify training adaptations in futsal players along with the suitability of heart-rate (HR) and HR-variability (HRV) measures to identify these adaptations. METHODS: Eleven male professional futsal players were assessed before (pretraining) and after (posttraining) a 5-wk period. Assessments included 5'-5' and Yo-Yo IR1 and IR2 performances and HR and HRV at rest and during the IR and 5'-5' tests. Magnitude-based-inference analyses examined the differences between pre- and posttraining, while relationships between changes in variables were determined via correlation. RESULTS: Posttraining, Yo-Yo IR1 performance likely increased while Yo-Yo IR2 performance almost certainly increased. Submaximal HR during the Yo-Yo IR1 and Yo-Yo IR2 almost certainly and likely, respectively, decreased with training. HR during the 5'-5' was very likely decreased, while HRV at rest and during the 5'-5' was likely increased after training. Changes in both Yo-Yo IR performances were negatively correlated with changes in HR during the Yo-Yo IR1 test and positively correlated with the change in HRV during the 5'-5'. CONCLUSIONS: The current study has identified the Yo-Yo IR2 as more responsive for monitoring training-induced changes of futsal players than the Yo-Yo IR1. Changes in submaximal HR during the Yo-Yo IR and HRV during the 5'-5' were highly sensitive to changes in maximal performance and are recommended for monitoring training. The 5'-5' was recommended as a time-efficient method to assess training adaptations for futsal players.

Effects of additional repeated sprint training during preseason on performance, heart rate variability, and stress symptoms in futsal players: a randomized controlled trial.

The aim of this study was to investigate whether supplementing regular preseason futsal training with weekly sessions of repeated sprints (RS) training would have positive effects on repeated sprint ability (RSA) and field test performance. Thirteen players from a professional futsal team (22.6 ± 6.7 years, 72.8 ± 8.7 kg, 173.2 ± 6.2 cm) were divided randomly into 2 groups (AddT: n = 6 and normal training group: n = 7). Both groups performed a RSA test, Yo-Yo intermittent recovery test level 1 (YoYo IR1), squat (SJ) and countermovement jumps (CMJ), body composition, and heart rate variability (HRV) measures at rest before and after 4 weeks of preseason training. Athletes weekly stress symptoms were recorded by psychometric responses using the Daily Analysis of Life Demands for Athletes questionnaire and subjective ratings of well-being scale, respectively. The daily training load (arbitrary units) was assessed using the session of rating perceived exertion method. After the preseason training, there were no significant changes for body composition, SJ, CMJ, and RSAbest. The YoYo IR1, RSAmean, RSAworst, and RSAdecreament were significantly improved for both groups (p ≤ 0.05). The HRV parameters improved significantly within both groups (p ≤ 0.05) except for high frequency (HF, absolute and normalized units, [n.u.]), low frequency (LF) (n.u.), and the LF/HF ratio. A moderate effect size for the AddT group was observed for resting heart rate and several HRV measures. Training load and psychometric responses were similar between both groups. Additional RS training resulted in slightly greater positive changes for vagal-related HRV with similar improvements in performance and training stress during the preseason training in futsal players.