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Romain Meeusen and Lieselot Decroix

stimuli to recall memorial representations of experiences with particular food items. These memorial representations can be pleasant or unpleasant (e.g., conditioned food/taste aversion). It is clear that nutrition (and supplements) will influence brain functioning. Nutrition provides the proper building

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Anna Skarpanska-Stejnborn, Lucja Pilaczynska-Szczesniak, Piotr Basta, and Ewa Deskur-Smielecka

The aim of this study was to investigate the effect of Rhodiola rosea supplementation on the balance of oxidants and antioxidants in the serum and erythrocytes of competitive rowers. This double-blinded study included 22 members of the Polish Rowing Team who were participating in a preparatory camp. Participants were randomly assigned to the supplemented group (n = 11), who received 100 mg of R. rosea extract twice daily for 4 wk, or the placebo group (n = 11). At the beginning and end of the study, participants performed a 2,000-m maximum test on a rowing ergometer. Blood samples were taken from the antecubital vein before each exercise test, 1 min after completing the test, and after a 24-hr restitution period. The following redox parameters were assessed in erythrocytes: superoxide dismutase activity, glutathione peroxidase activity, and thiobarbituric-acid-reactive substances concentrations. In addition, creatine kinase activity and total antioxidant capacity were measured in plasma samples, lactate levels were determined in capillary blood samples, and uric acid concentrations were measured in serum. After supplementation, the total plasma antioxidant capacity was significantly higher (p = .0002) in the supplemented group than in the placebo group, and superoxide dismutase activity in erythrocytes directly after and 24 hr after the ergometry was significantly (p = .0461) lower in athletes receiving R. rosea extracts than in the placebo group. In conclusion, supplementation with R. rosea increased antioxidant levels in the plasma of professional rowers but had no effect on oxidative damage induced by exhaustive exercise.

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International Olympic Committee Expert Group on Dietary Supplements in Athletes

Dietary supplements encompass a wide range of products, including essential nutrients (vitamins, minerals, proteins, amino acids, etc.), herbals and botanicals, and specific products with potential for maintenance of health and optimisation of performance. The use of dietary supplements is

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Scott C. Forbes, Nathan Sletten, Cody Durrer, Étienne Myette-Côté, D. Candow, and Jonathan P. Little

High-intensity interval training (HIIT) has been shown to improve cardiorespiratory fitness, performance, body composition, and insulin sensitivity. Creatine (Cr) supplementation may augment responses to HIIT, leading to even greater physiological adaptations. The purpose of this study was to determine the effects of 4 weeks of HIIT (three sessions/week) combined with Cr supplementation in recreationally active females. Seventeen females (age = 23 ± 4 yrs; BMI = 23.4 ± 2.4) were randomly assigned to either Cr (Cr; 0.3 g・kg-1・d-1 for 5 d followed by 0.1 g・kg-1・d-1 for 23 days; n = 9) or placebo (PLA; n = 8). Before and after the intervention, VO2peak, ventilatory threshold (VT), time-trial performance, lean body mass and fat mass, and insulin sensitivity were assessed. HIIT improved VO2peak (Cr = +10.2%; PLA = +8.8%), VT (Cr = +12.7%; PLA = +9.9%), and time-trial performance (Cr = -11.5%; PLA = -11.6%) with no differences between groups (time main effects, all p < .001). There were no changes over time for fat mass (Cr = -0.3%; PLA = +4.3%), whole-body lean mass (Cr = +0.5%; PLA = -0.9%), or insulin resistance (Cr = +3.9%; PLA = +18.7%). In conclusion, HIIT is an effective way to improve cardiorespiratory fitness, VT, and time-trial performance. The addition of Cr to HIIT did not augment improvements in cardiorespiratory fitness, performance or body composition in recreationally active females.

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Katharina Diehl, Ansgar Thiel, Stephan Zipfel, Jochen Mayer, Alexia Schnell, and Sven Schneider

The authors’ aim was to examine the prevalence of (daily) dietary-supplement (DS) use among elite adolescent athletes and to differentiate use by different types of DS according to their function. Data were analyzed for associations between users of these DS types, sociodemographic, sport-specific characteristics, and opinion on the need for DS. In addition, sources of supply and information were examined. In the framework of the GOAL Study, 1,138 German elite adolescent athletes (14–18 yr) answered questions about DS. The data were analyzed to identify groups at risk for using DS after a classification by supplemental function. Of the young athletes, 91.1% reported DS use during the previous month. (Daily) DS use was significantly associated with sex, kind of sport, and the weekly duration of sporting activity. Furthermore, some athletes were required to use DS by their sporting organization. DS use was more likely in these athletes than in those whose sporting organizations had no such requirement. Overall, DS with short- and long-term supplemental function were mostly associated with the use of magnesium. However, DS with medium-term muscle-building function played an important role among daily users. The main source of information about DS was coaches; main source of supply was parents. Professional education is urgently needed, as 9 out of 10 athletes used DS, and strong positive opinions toward the use of DS were present, particularly in the DS users.

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Rebecca L. Jones, Trent Stellingwerff, Paul Swinton, Guilherme Giannini Artioli, Bryan Saunders, and Craig Sale

moderate positive effect size on exercise outcomes ( Christensen et al., 2017 ; Matson & Tran, 1993 ; Peart et al., 2012 ), with larger effect sizes in nontrained individuals compared to trained athletes ( Peart et al., 2012 ). Accordingly, SB is one of few performance-enhancing supplements with ample

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Christopher Tack, Faye Shorthouse, and Lindsy Kass

Dietary supplements are defined as any concentrated source of a nutritional compound demonstrating a physiological effect ( Department of Health, 2011 ). A meta-analysis ( n  = 159) showed greater usage of supplements in athletes compared with nonathletes with increasing frequency in elite

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Rianne Costello, Mark E.T. Willems, Stephen D. Myers, Fiona Myers, Nathan A. Lewis, Ben J. Lee, and Sam D. Blacker

) and via indirect markers measured systemically in plasma, such as creatine kinase and inflammatory cytokines (e.g., interleukin-6 [IL-6]) and muscle soreness ( Clarkson & Hubal, 2002 ; Hyldahl & Hubal, 2014 ). Recently, foods and supplements that are rich in polyphenols, such as berries and fruits

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Philippe Richard, Lymperis P. Koziris, Mathieu Charbonneau, Catherine Naulleau, Jonathan Tremblay, and François Billaut

-skating competitions 4 highlight the importance of efficient recovery for successful performances. Dietary nitrate consumption has become progressively more popular among athletes. 5 Nitrate (NO 3 − ) supplementation via beetroot juice or as salt (NaNO 3 − ) increases nitric oxide (NO) bioavailability. NO is a

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Vincent G. Kelly, Liam S. Oliver, Joanna Bowtell, and David G. Jenkins

the athletes in this study, young male RL players should focus on evenly distributing protein intakes of 2.0–2.6 g·kg −1 ·day −1 , possibly including supplements after training. Therefore, suggestions of how general athlete guidelines ( Burke et al., 2011 ; Thomas et al., 2016 ) may translate to RL