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Short-term branched-chain amino acid supplementation does not enhance vertical jump in professional volleyball players. A double-blind, controlled, randomized study.
Martín-Martínez, JP, Calleja Gonzalez, J, Adsuar Sala, JC, Gómez-Pomares, S, Carlos-Vivas, J, Pérez-Gómez, J
Nutricion hospitalaria. 2020;(5):1007-1011
Abstract
To the best of the authors' knowledge, no previous studies have described the effect of branched-chain amino acids (BCAA) on vertical performance during a week in professional volleyball players. This study assessed BCAA supplementation for a week, aiming to improve vertical jump performance in male professional volleyball players. Twelve male volleyballers were randomly assigned to a BCAA group (n = 6) or a control group (n = 6). The BCAA group ingested 21 g over a week, 7 g per day on Monday, Wednesday, and Friday, before a volleyball training session, while the control group drank a placebo drink. Participants performed 8 maximal countermovement jumps (CMJ); the 3 CMJs on Monday and Wednesday were evaluated after warm-up, after plyometric training, and at the end of the training session; and the 2 CMJs on Friday were evaluated after warm-up, and at the end of the training session. Compared with baseline, no significant differences in CMJ over the week were observed in BCAA or control group, neither between groups. The results indicated that 21 g of BCAA supplementation over a week did not improve vertical jump performance in professional volleyball players.
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Recovery after volleyball: a narrative review.
Closs, B, Burkett, C, Trojan, JD, Brown, SM, Mulcahey, MK
The Physician and sportsmedicine. 2020;(1):8-16
Abstract
Volleyball is a popular sport, but there has been little research to date investigating the recovery process. Volleyball involves short bouts of high intensity exertion, often with limited time to rest between matches. This literature review highlights the specific methods used to recover after playing volleyball and evaluates their effectiveness. Recovery strategies have been shown to increase performance and prevent injury. Specific techniques identified include nutritional strategies, proper sleep, mental and psychological techniques, cold water immersion, and laser therapy. Some, such as nutrition and sleep, have been definitively shown to benefit volleyball players, while others, such as cold water immersion and laser therapy, have shown promise but require further research to determine their overall effect. Other areas of future research include evaluating the effectiveness of combined recovery techniques as well as determining which are best for rapid recovery.
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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, Nakamura, FY
Journal of strength and conditioning research. 2019;(2):502-513
Abstract
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.
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Female Volleyball Players Are More Prone to Cortisol Anticipatory Stress Response than Sedentary Women.
Dziembowska, I, Wójcik, M, Hołyńska-Iwan, I, Litwic-Kaminska, K, Słomka, A, Żekanowska, E
Medicina (Kaunas, Lithuania). 2019;(6)
Abstract
Background and Objectives: Top-level sports performance places heavy physical and psychological demands on elite-level athletes, which can be a source of increased levels of stress. Therefore, high-level volleyball players may present altered cardiovascular and endocrinological stress response during stressful events. Although many previous studies have examined the response to stress on athletes, most of them regarded only males, while the impact of the female menstrual cycle has rarely been taken into account. We aimed to study psychophysiological response to anticipatory stressor through analysis of heart rate, self-reported anxiety level, and salivary cortisol in healthy young female athletes by minimalizing the effect of confounders. Materials and Methods: A total of 55 females (25 members of the best league for female volleyball players in Poland and 30 sedentary-lifestyle control subjects) in the follicular phase of their menstrual cycle were exposed to mental arithmetic tasks as an experimental imitation of the stressor. Volleyball players were significantly taller than sedentary individuals (177.1 ± 3.4 cm vs. 173.3 ± 3.4 cm, respectively, p = 0.034), but did not differ in weight (73.6 ± 5.2 kg vs. 70 ± 4.23 kg, respectively, p = 0.081), body mass index (BMI) (23.5 ± 1.13 vs. 24.1 ± 1.45, respectively, p = 0.060), and age (22 ± 1.11 vs. 23 ± 1.14 years, respectively, p = 0.2). Their stress responses were assessed through self-reported anxiety levels and physiological measurements of salivary cortisol concentrations and heart rate (HR). Results: For HR, significant effects of time (F(2,120) = 21.34, p < 0.001, η2 = 0.26) were found, but not for training status (F(1,60) = 2.69, p = 0.106, η2 = 0.04). For cortisol levels, the analysis showed the main effects of time (F(3,180) = 11.73, p < 0.001, η2 = 0.16) and training status (F(1,60) = 4.69, p = 0.034, η2 = 0.07) and a significant interaction between training status and time (F(3,180) = 3.07, p = 0.029, η2 = 0.05). Post-hoc analyses showed higher cortisol concentrations among volleyball players following the math task (all p < 0.001), as well as higher cortisol concentrations in S2, S3, and S4 compared to S1 in volleyball players (all p < 0.001). We observed also a significant increase in state anxiety in both groups (all p < 0.001), but no differences in state anxiety levels between groups. Conclusion: Female volleyball players may not differ in subjective graduation of stressors; however, exposure to training-based stressors seems to promote cortisol response to the anticipated stressor.