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1.
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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2.
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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3.
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.
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4.
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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5.
Effects of Caffeine on Countermovement-Jump Performance Variables in Elite Male Volleyball Players.
Zbinden-Foncea, H, Rada, I, Gomez, J, Kokaly, M, Stellingwerff, T, Deldicque, L, Peñailillo, L
International journal of sports physiology and performance. 2018;(2):145-150
Abstract
PURPOSE To examine the effects of a moderate dose of caffeine in elite male volleyball players on countermovement-jump (CMJ) performance, as well as temporal concentric- and eccentric-phase effects. METHODS Ten elite male volleyball players took part in 2 experimental days via a randomized crossover trial 1 wk apart in which they ingested either 5 mg/kg of caffeine or a placebo in double-blind fashion. Heart rate and blood pressure were measured at rest and 60 min postingestion. Afterward, subjects also performed 3 CMJ trials 60 min postingestion, of which the average was used for further analysis. They filled out a questionnaire on possible side effects 24 h posttrial. RESULTS Caffeine intake, compared with placebo, increased CMJ peak concentric force (6.5% ± 6.4%; P = .01), peak power (16.2% ± 8.3%; P < .01), flight time (5.3% ± 3.4%; P < .01), velocity at peak power (10.6% ± 8.0%; P < .01), peak displacement (10.8% ± 6.5%; P < .01), peak velocity (12.6% ± 7.4%; P < .01), peak acceleration (13.5% ± 8.5%; P < .01), and the force developed at peak power (6.0% ± 4.0%; P < .01) and reduced the time between peak power and peak force (16.7% ± 21.6%, P = .04). Caffeine increased diastolic blood pressure by 13.0% ± 8.9% (P < .05), whereas no adverse side effects were found. CONCLUSIONS The ingestion of 5 mg/kg of anhydrous caffeine improves overall CMJ performance without inducing side effects.
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6.
Total and regional bone mineral and tissue composition in female adolescent athletes: comparison between volleyball players and swimmers.
Valente-Dos-Santos, J, Tavares, ÓM, Duarte, JP, Sousa-E-Silva, PM, Rama, LM, Casanova, JM, Fontes-Ribeiro, CA, Marques, EA, Courteix, D, Ronque, ERV, et al
BMC pediatrics. 2018;(1):212
Abstract
BACKGROUND Exploring the osteogenic effect of different bone-loading sports is particular relevant to understand the interaction between skeletal muscle and bone health during growth. This study aimed to compare total and regional bone and soft-tissue composition between female adolescent swimmers (n=20, 15.71±0.93 years) and volleyball players (n=26, 16.20±0.77 years). METHODS Dietary intake was obtained using food frequency questionnaires. Body size was given by stature, sitting height, and body mass. Six skinfolds were measured. Bone mineral content (BMC) and density (BMD), lean soft tissue, and fat tissue were assessed using dual-energy X-ray absorptiometry. Pearson's product moment correlation coefficients were calculated to examine the relationships among variables, by type of sport. Comparisons between swimmers and volleyball players were performed using student t-tests for independent samples and multivariate analysis of covariance (controlling for age, training history and body size). RESULTS Swimmers (BMC: 2328±338 g) and volleyball players (BMC: 2656±470 g) exceeded respectively by 2.1 and 2.8 standard deviation scores the average of international standards for whole body BMC of healthy adolescents. Years of training in swimmers were positively related to the upper limbs BMC (r=+0.49, p<0.05). In volleyball players, years of training correlated significantly with lower limbs BMD (r=+0.43, p<0.05). After adjustments for potential confounders, moderate differences (ES-r=0.32) between swimmers and volleyball players were noted in BMD at the lower limbs (volleyball players: +0.098 g∙cm-2, +7.8%). CONCLUSIONS Youth female athletes who participate in high-intensity weight-loading activities such as volleyball exhibit moderately higher levels of BMD at the lower limbs compared to non-loading sports such as swimming.
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7.
Eleven Weeks of Iron Supplementation Does Not Maintain Iron Status for an Entire Competitive Season in Elite Female Volleyball Players: A Follow-Up Study.
Mielgo-Ayuso, J, Zourdos, MC, Calleja-González, J, Córdova, A, Fernandez-Lázaro, D, Caballero-García, A
Nutrients. 2018;(10)
Abstract
BACKGROUND Even though iron supplementation can be effective, it is necessary to be cautious of toxicity and aim to do no harm, therefore, it is important to examine the length of time the benefits of iron supplementation can be maintained following its cessation. The main purpose of this study was to analyze if iron stores and strength performance were maintained in elite female volleyball players for the final 18 weeks of a competitive season following the cessation of 11 weeks of iron supplementation. METHODS Twenty-two volleyballers (age: 27.0 ± 5.6 years.) were assigned to two groups (iron treatment group-ITG, n = 11 or control gropu-CG, n = 11) at the beginning of a previous trial (T0) and ITG consumed 325mg/d of ferrous sulphate for 11 weeks (T11). Then, in the present study iron status and strength were measured again 10 (T21) and 18 weeks later (T29) after the cessation of supplementation. RESULTS At the end of the previous trial (T11), ITG maintained iron status as measured by hematological parameters (serum iron-sFE, serum ferritin-FER, transferrin saturation index-TSI, and hemogloblin-Hb), however, CG showed a decrease in these markers at T11. Further, from T0 to T11 ITG experienced greater (p < 0.05) changes in clean and jerk, power clean, and total mean strength (TMS-sum of all strength tests) than CG. In the present, follow-up investigation, there was a group-by-time interaction in favor of CG vs. ITG from T11 to T21 for FER (p = 0.028) and Hb (p = 0.042). Further, there was an increase for CG (p < 0.001) in power clean for CG from T11 (38.4 ± 1.7 kg) to T21 (41.3 ± 1.9 kg) and T29 (41.8 ± 1.7 kg), but no change for power clean in ITG (p > 0.05). A group-by-time interaction from T11 to T29 occurred in favor of CG for half-squat (p = 0.049) and TMS (p = 0.049). CONCLUSION Our findings suggest that the benefits of iron supplementation are not sustained in elite female volleyballers if supplementation is ceased for 18 weeks.
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8.
Decreased Circulating mtDNA Levels in Professional Male Volleyball Players.
Nasi, M, Cristani, A, Pinti, M, Lamberti, I, Gibellini, L, De Biasi, S, Guazzaloca, A, Trenti, T, Cossarizza, A
International journal of sports physiology and performance. 2016;(1):116-21
Abstract
PURPOSE Exercise exerts various effects on the immune system, and evidence is emerging on its anti-inflammatory effects; the mechanisms on the basis of these modifications are poorly understood. Mitochondrial DNA (mtDNA) released from damaged cells acts as a molecule containing the so-called damage-associated molecular patterns and can trigger sterile inflammation. Indeed, high plasma levels of mtDNA are associated to several inflammatory conditions and physiological aging and longevity. The authors evaluated plasma mtDNA in professional male volleyball players during seasonal training and the possible correlation between mtDNA levels and clinical parameters, body composition, and physical performance. METHODS Plasma mtDNA was quantified by real-time PCR every 2 mo in 12 professional volleyball players (PVPs) during 2 consecutive seasons. As comparison, 20 healthy nonathlete male volunteers (NAs) were analyzed. RESULTS The authors found lower levels of mtDNA in plasma of PVPs than in NAs. However, PVPs showed a decrease of circulating mtDNA only in the first season, while no appreciable variations were observed during the second season. No correlation was observed among mtDNA, hematochemical, and anthropometric parameters. CONCLUSIONS Regular physical activity appeared associated with lower levels of circulating mtDNA, further confirming the protective, anti-inflammatory effect of exercise.
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9.
Isometric exercise induces analgesia and reduces inhibition in patellar tendinopathy.
Rio, E, Kidgell, D, Purdam, C, Gaida, J, Moseley, GL, Pearce, AJ, Cook, J
British journal of sports medicine. 2015;(19):1277-83
Abstract
BACKGROUND Few interventions reduce patellar tendinopathy (PT) pain in the short term. Eccentric exercises are painful and have limited effectiveness during the competitive season. Isometric and isotonic muscle contractions may have an immediate effect on PT pain. METHODS This single-blinded, randomised cross-over study compared immediate and 45 min effects following a bout of isometric and isotonic muscle contractions. Outcome measures were PT pain during the single-leg decline squat (SLDS, 0-10), quadriceps strength on maximal voluntary isometric contraction (MVIC), and measures of corticospinal excitability and inhibition. Data were analysed using a split-plot in time-repeated measures analysis of variance (ANOVA). RESULTS 6 volleyball players with PT participated. Condition effects were detected with greater pain relief immediately from isometric contractions: isometric contractions reduced SLDS (mean±SD) from 7.0±2.04 to 0.17±0.41, and isotonic contractions reduced SLDS (mean±SD) from 6.33±2.80 to 3.75±3.28 (p<0.001). Isometric contractions released cortical inhibition (ratio mean±SD) from 27.53%±8.30 to 54.95%±5.47, but isotonic contractions had no significant effect on inhibition (pre 30.26±3.89, post 31.92±4.67; p=0.004). Condition by time analysis showed pain reduction was sustained at 45 min postisometric but not isotonic condition (p<0.001). The mean reduction in pain scores postisometric was 6.8/10 compared with 2.6/10 postisotonic. MVIC increased significantly following the isometric condition by 18.7±7.8%, and was significantly higher than baseline (p<0.001) and isotonic condition (p<0.001), and at 45 min (p<0.001). CONCLUSIONS A single resistance training bout of isometric contractions reduced tendon pain immediately for at least 45 min postintervention and increased MVIC. The reduction in pain was paralleled by a reduction in cortical inhibition, providing insight into potential mechanisms. Isometric contractions can be completed without pain for people with PT. The clinical implications are that isometric muscle contractions may be used to reduce pain in people with PT without a reduction in muscle strength.
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10.
Acute Consumption of an Energy Drink Does Not Improve Physical Performance of Female Volleyball Players.
Fernández-Campos, C, Dengo, AL, Moncada-Jiménez, J
International journal of sport nutrition and exercise metabolism. 2015;(3):271-7
Abstract
To determine the acute effect of an energy drink (ED) on physical performance of professional female volleyball players. 19 females (age= 22.3 ± 4.9 yr.; height= 171.8 ± 9.4 cm; weight= 65.2 ± 10.1 kg) participated in a randomized, crossover, double-blind study to measure grip strength, vertical jump and anaerobic power in 3 different sessions (ED, placebo [PL] or no beverage [CTL]). For each session, participants arrived in a fasted state, consumed a standardized breakfast meal, and 1 hr later completed the 3 baseline performance tests without having ingested the beverage. After completing the premeasurements, the athletes drank 6 ml/kg of body weight of the ED or PL and in the CTL condition no beverage was consumed. Posttest measurements were taken 30 min after the ingestion of liquids. A 3 × 2 repeated-measures ANOVA revealed no significant within-session and measurement time interactions for each performance test. Regardless of the measurement time, right hand grip strength was significantly higher in the ED condition (34.6 ± 0.9 kg) compared with PL (33.4 ± 1.1 kg) and CTL (33.6 ± 1.0 kg) (p < 0.05). Regardless of the beverage ingested, averaged right hand grip strength, taking into account all 3 testing conditions, increased from pre to posttesting (Pre = 33.8 ± 0.9 kg vs. Post = 33.9 ± 1.0 kg; p = 0.029), as did the averaged fatigue index, obtained from the anaerobic power test (Pre = 65.9± 2.2% vs. Post = 68.7± 2.0%; p= 0.049). The acute ingestion of an ED did not improve physical performance of professional Costa Rican female volleyball players.