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Open access

Iñigo Mujika and Ritva S. Taipale

Open access

Ralph Beneke and Renate M. Leithäuser

Open access

Jos J. de Koning and Dionne A. Noordhof

Full access

Fiona Pelly and Susie Parker Simmons

Food provision at the Olympic Games has evolved considerably since the advent of a unified menu, but there are challenges in existing catering for the expanding cultural and sporting diversity. Continuity between events is difficult due to the changes in location, organizing committees, caterers, athletes, support staff, and volunteers. Independent review of the food provision by sports nutrition experts has been implemented to help establish some consistency between Olympic Games. The aim of this study was to compare an expert desk top and onsite review of the food provided at the Rio 2016 Olympic Games, and compare this with a similar review at the London 2012 Olympic Games. A previously developed survey was completed by sports nutrition experts 6 months prior to the opening of the Rio 2016 Olympic village and during the Olympic Games in September 2016. Questions about the food provision included both scaled and open-ended responses. There was a significantly lower rating for menu variety onsite (p = .025) versus the desk top review. All aspects of the menu and the ability to cater for specific situations rated as average or less. A significantly (p = .007) lower overall median rating was obtained for Rio (five out of 10) compared with London (eight out of 10), with hot gluten-free items rated as poor at both events. Comments from experts related to lack of variety, sports and recovery foods, absence of signage, and inaccurate nutrition labeling. An improved process for expert nutrition review at these events is warranted.

Open access

Keith Baar

Patellar tendinopathy is one of the most common afflictions in jumping sports. This case study outlines the rehabilitation of a professional basketball player diagnosed by magnetic resonance imaging (MRI) with a central core patellar tendinopathy within the proximal enthesis. The player undertook a nutrition and strength-based rehabilitation program combining gelatin ingestion and heavy isometric loading of the patellar tendon designed to produce significant stress relaxation as part of their competition schedule and a whole-body training plan. On follow-up one and a half years into the program an independent orthopedic surgeon declared the tendon normal on MRI. Importantly, the improved MRI results were associated with a decrease in pain and improved performance. This case study provides evidence that a nutritional intervention combined with a rehabilitation program that uses stress relaxation can improve clinical outcomes in elite athletes.

Open access

Edgar J. Gallardo and Andrew R. Coggan

Consumption of beetroot juice (BRJ) supplements has become popular among athletes because beets tend to be rich in nitrate (NO3 ), which can enhance exercise performance by increasing nitric oxide production. The NO3 content of beets can vary significantly, however, making it difficult to know how much NO3 any product actually contains. Samples from 45 different lots of 24 different BRJ products from 21 different companies were therefore analyzed for NO3 (and nitrite [NO2 ]) concentration using high-performance liquid chromatography. The NO3 and NO2 content (i.e., amount per serving) was then calculated based on either (a) the manufacturer’s recommended serving size (for prepackaged/single dose products) or (b) as used in previous studies, a volume of 500 ml (for BRJ sold in bulk containers). There was moderate-to-large variability in NO3 content between samples of the same product, with a mean coefficient of variation of 30% ± 26% (range 2–83%). There was even greater variability between products, with a ∼50-fold range in NO3 content between the lowest and highest. Only five products consistently provided ≥5 mmol of NO3 /serving, which seems to be the minimal dose required to enhance exercise performance in most individuals. NO2 contents were generally low (i.e., ≤0.5% compared with NO3 ), although two products contained 10% and 14%. The results of this study may be useful to athletes and their support staff contemplating which (if any) BRJ product to utilize. These data may also offer insight into variability in the literature with respect to the effects of BRJ on exercise performance.

Open access

Shona L. Halson, Alan G. Hahn, and Aaron J. Coutts

Open access

Trent Stellingwerff, Ingvill Måkestad Bovim, and Jamie Whitfield

Middle-distance runners utilize the full continuum of energy systems throughout training, and given the infinite competition tactical scenarios, this event group is highly complex from a performance intervention point of view. However, this complexity results in numerous potential periodized nutrition interventions to optimize middle-distance training adaptation and competition performance. Middle-distance race intensity is extreme, with 800- to 5,000-m races being at ∼95% to 130% of VO2max. Accordingly, elite middle-distance runners have primarily Type IIa/IIx fiber morphology and rely almost exclusively on carbohydrate (primarily muscle glycogen) metabolic pathways for producing adenosine triphosphate. Consequently, the principle nutritional interventions that should be emphasized are those that optimize muscle glycogen contents to support high glycolytic flux (resulting in very high lactate values, of >20 mmol/L in some athletes) with appropriate buffering capabilities, while optimizing power to weight ratios, all in a macro- and microperiodized manner. From youth to elite level, middle-distance athletes have arduous racing schedules (10–25 races/year), coupled with excessive global travel, which can take a physical and emotional toll. Accordingly, proactive and integrated nutrition planning can have a profound recovery effect over a long race season, as well as optimizing recovery during rounds of championship racing. Finally, with evidence-based implementation and an appropriate risk/reward assessment, several ergogenic aids may have an adaptive and/or performance-enhancing effect in the middle-distance athlete. Given that elite middle-distance athletes undertake ∼400 to 800 training sessions with 10–25 races/year, there are countless opportunities to implement various periodized acute and chronic nutrition-based interventions to optimize performance.