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Ronald J. Maughan, Louise M. Burke, Jiri Dvorak, D. Enette Larson-Meyer, Peter Peeling, Stuart M. Phillips, Eric S. Rawson, Neil P. Walsh, Ina Garthe, Hans Geyer, Romain Meeusen, Luc van Loon, Susan M. Shirreffs, Lawrence L. Spriet, Mark Stuart, Alan Vernec, Kevin Currell, Vidya M. Ali, Richard G.M. Budgett, Arne Ljungqvist, Margo Mountjoy, Yannis Pitsiladis, Torbjørn Soligard, Uğur Erdener and Lars Engebretsen

Dietary supplements are used by athletes at all levels of sport, reflecting the prevalence of their use in the wider society. About half of the adult US population uses some form of dietary supplements ( Bailey et al., 2011 ) and, though there are regional, cultural, and economic differences, a

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Louise M. Burke and Peter Peeling

A common discussion point among experienced sports scientists, especially those who serve on journal editorial boards with opportunities to vet incoming manuscripts, is that studies of supplements and sports performance seem to be considered an entry point to the world of sports nutrition research

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Gabriel Motta Pinheiro Brisola, Elvis de Souza Malta, Paulo Roberto Pereira Santiago, Luiz Henrique Palucci Vieira and Alessandro Moura Zagatto

, 2 and a decrease in time spent in sprints and other high-intensity actions (from 18.1% to 12.6%). 7 In this way, some studies have recently used β-alanine supplementation in water polo 8 – 10 in an attempt to avoid the deleterious effects of acidosis on muscle, and some positive findings were

Open access

Eric S. Rawson, Mary P. Miles and D. Enette Larson-Meyer

Several dietary supplements, including carbohydrate, caffeine, creatine monohydrate, nitrate, beta-alanine, and sodium bicarbonate, are well-established performance enhancers (see Peeling et al., 2018 ). Additionally, the beneficial effects of protein on the adaptive response to exercise has been

Open access

Peter Peeling, Martyn J. Binnie, Paul S.R. Goods, Marc Sim and Louise M. Burke

these underpinning factors are accounted for, and the athlete reaches a training maturity and competition level where marginal gains determine success, a role may exist for the use of evidence-based performance supplements. Although an array of supplements are marketed for the enhancement of sports

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Elliot R. Cooper, Kristine C.Y. McGrath, XiaoHong Li and Alison K. Heather

Athletes of all ages, from amateurs to professional, use sport supplements. Reasons for supplement use include enhanced performance or recovery, muscle mass gain, or improved appearance ( Kiertscher & DiMarco, 2013 ). The use of supplements by athletes in some sports (e.g., bodybuilding) is

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Paraskevi Detopoulou and Vasilios Papamikos

Omega-3 fatty acids exert a plethora of physiological actions including triglycerides lowering, reduction of inflammatory indices, immunomodulation, anti- thrombotic effects and possibly promotion of exercise performance. Their use is widespread and for commonly ingested doses their side- effects are minimal. We report a case of a 60y amateur athlete who consumed about 20 g omega-3 fatty acids daily from supplements and natural sources for a year. After the intake of cortisone and antibiotics he presented duodenum ulcer and bleeding although he had no previous history of gastrointestinal problems. Although several animal data support gastro-protective effects of omega-3 fatty acids in the present case they were not able to prevent ulcer generation. The present observation may be explained by (i) the high dose of omega-3 fatty acids and their effect on bleeding, (ii) the fact that cortisone increases their oxidation and may render them proinflammatory, (iii) other antithrombotic microconstituents included in the consumed cod-oil and/or the diet of the subject and (iv) the differences in the coagulation and fibrinolytic systems of well- trained subjects. Further studies are needed to substantiate any possible interaction of cortisone and omega-3 fatty acids in wide ranges of intake.

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Matthew W. Hoon, Andrew M. Jones, Nathan A. Johnson, Jamie R. Blackwell, Elizabeth M. Broad, Bronwen Lundy, Anthony J. Rice and Louise M. Burke

Context:

Beetroot juice is a naturally rich source of inorganic nitrate (NO3 ), a compound hypothesized to enhance endurance performance by improving exercise efficiency.

Purpose:

To investigate the effect of different doses of beetroot juice on 2000-m ergometer-rowing performance in highly trained athletes.

Methods:

Ten highly trained male rowers volunteered to participate in a placebo-controlled, double-blinded crossover study. Two hours before undertaking a 2000-m rowing-ergometer test, subjects consumed beetroot juice containing 0 mmol (placebo), 4.2 mmol (SINGLE), or 8.4 mmol (DOUBLE) NO3 . Blood samples were taken before supplement ingestion and immediately before the rowing test for analysis of plasma [NO3 ] and [nitrite (NO2 )].

Results:

The SINGLE dose demonstrated a trivial effect on time to complete 2000 m compared with placebo (mean difference: 0.2 ± 2.5 s). A possibly beneficial effect was found with DOUBLE compared with SINGLE (mean difference –1.8 ± 2.1 s) and with placebo (–1.6 ± 1.6 s). Plasma [NO2 ] and [NO3 ] demonstrated a dose-response effect, with greater amounts of ingested nitrate leading to substantially higher concentrations (DOUBLE > SINGLE > placebo). There was a moderate but insignificant correlation (r = –.593, P = .055) between change in plasma [NO2 ] and performance time.

Conclusion:

Compared with nitratedepleted beetroot juice, a high (8.4 mmol NO3 ) but not moderate (4.2 mmol NO3 ) dose of NO3 in beetroot juice, consumed 2 h before exercise, may improve 2000-m rowing performance in highly trained athletes.

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Mayur K. Ranchordas, Laurent Bannock and Scott L. Robinson

Professional soccer players are exposed to large amounts of physiological and psychological stress, which can increase infection risk and threaten availability for training and competition. Accordingly, it is important for practitioners to implement strategies that support player well-being and prevent illness. This case study demonstrates how a scientifically supported and practically applicable nutrition and lifestyle strategy can reduce infection incidence in an illness-prone professional soccer player. In the 3 months before the intervention, the player had 3 upper-respiratory tract infections (URTIs) and subsequently missed 3 competitive matches and 2 weeks’ training. He routinely commenced morning training sessions in the fasted state and was estimated to be in a large daily energy deficit. Throughout the 12-week intervention, the amount, composition, and timing of energy intake was altered, quercetin and vitamin D were supplemented, and the player was provided with a daily sleep and hygiene protocol. There was a positive increase in serum vitamin D 25(OH) concentration from baseline to Week 12 (53 n·mol-1 to 120 n·mol-1) and salivary immunoglobulin-A (98 mg·dl-1 to 135 mg·dl-1), as well as a decline in the number of URTI symptoms (1.8 ± 2.0 vs. 0.25 ± 0.5 for Weeks 0–4 and Weeks 8–12, respectively). More important, he maintained availability for all training and matches over the 12-week period. We offer this case study as a real-world applied example for other players and practitioners seeking to deploy nutrition and lifestyle strategies to reduce risk of illness and maximize player availability.

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Martin C. Waller, Deborah A. Kerr, Martyn J. Binnie, Emily Eaton, Clare Wood, Terreen Stenvers, Daniel F. Gucciardi, Carmel Goodman and Kagan J. Ducker

Supplements are often used to optimize nutrition, or to enhance health and performance, with usage rates of 37–93% among elite athletes ( Giannopoulou et al., 2013 ; Knapik et al., 2016 ; Sato et al., 2015 ). The large variance in supplement usage rates may be due to the varying definitions of