IOC Consensus Statement: Dietary Supplements and the High-Performance Athlete.

Nutrition usually makes a small but potentially valuable contribution to successful performance in elite athletes, and dietary supplements can make a minor contribution to this nutrition program. Nonetheless, supplement use is widespread at all levels of sport. Products described as supplements target different issues, including the management of micronutrient deficiencies, supply of convenient forms of energy and macronutrients, and provision of direct benefits to performance or indirect benefits such as supporting intense training regimens.

IOC consensus statement: dietary supplements and the high-performance athlete.

Nutrition usually makes a small but potentially valuable contribution to successful performance in elite athletes, and dietary supplements can make a minor contribution to this nutrition programme. Nonetheless, supplement use is widespread at all levels of sport. Products described as supplements target different issues, including (1) the management of micronutrient deficiencies, (2) supply of convenient forms of energy and macronutrients, and (3) provision of direct benefits to performance or (4) indirect benefits such as supporting intense training regimens.

The Effect of Postexercise Carbohydrate and Protein Ingestion on Bone Metabolism.

Purpose: This study aimed to investigate the effect of feeding carbohydrate and protein (CHO + PRO), immediately or 2 h after an exhaustive run, on the bone turnover response in endurance runners.

Methods: Ten men (age = 28 ± 5 yr, height = 1.74 ± 0.

Postexercise High-Fat Feeding Suppresses p70S6K1 Activity in Human Skeletal Muscle.

Purpose: This study aimed to examine the effects of reduced CHO but high postexercise fat availability on cell signaling and expression of genes with putative roles in regulation of mitochondrial biogenesis, lipid metabolism, and muscle protein synthesis.

Methods: Ten males completed a twice per day exercise model (3.5 h between sessions) comprising morning high-intensity interval training (8 × 5 min at 85% V˙O2peak) and afternoon steady-state (SS) running (60 min at 70% V˙O2peak).

Parathyroid Hormone Secretion Is Controlled by Both Ionized Calcium and Phosphate During Exercise and Recovery in Men.

Context: The mechanism by which PTH is controlled during and after exercise is poorly understood due to insufficient temporal frequency of measurements.

Objective: The objective of the study was to examine the temporal pattern of PTH, PO4, albumin-adjusted calcium, and Ca(2+) during and after exercise.

Design And Setting: This was a laboratory-based study with a crossover design, comparing 30 minutes of running at 55%, 65%, and 75% maximal oxygen consumption, followed by 2.

Utilizing small nutrient compounds as enhancers of exercise-induced mitochondrial biogenesis.

Endurance exercise, when performed regularly as part of a training program, leads to increases in whole-body and skeletal muscle-specific oxidative capacity. At the cellular level, this adaptive response is manifested by an increased number of oxidative fibers (Type I and IIA myosin heavy chain), an increase in capillarity and an increase in mitochondrial biogenesis. The increase in mitochondrial biogenesis (increased volume and functional capacity) is fundamentally important as it leads to greater rates of oxidative phosphorylation and an improved capacity to utilize fatty acids during sub-maximal exercise.

Carbohydrate ingestion improves performance of a new reliable test of soccer performance.

The aim of the study was to investigate the reliability of a new test of soccer performance and evaluate the effect of carbohydrate (CHO) on soccer performance. Eleven university footballers were recruited and underwent 3 trials in a randomized order. Two of the trials involved ingesting a placebo beverage, and the other, a 7.

Effect of beverage glucose and sodium content on fluid delivery.

Background: Rapid fluid delivery from ingested beverages is the goal of oral rehydration solutions (ORS) and sports drinks.

Objective: The aim of the present study was to investigate the effects of increasing carbohydrate and sodium content upon fluid delivery using a deuterium oxide (D2O) tracer.

Design: Twenty healthy male subjects were divided into two groups of 10, the first group was a carbohydrate group (CHO) and the second a sodium group (Na).

Plasma deuterium oxide accumulation following ingestion of different carbohydrate beverages.

Optimal fluid delivery from carbohydrate solutions such as oral rehydration solutions or sports drinks is essential. The aim of the study was to investigate whether a beverage containing glucose and fructose would result in greater fluid delivery than a beverage containing glucose alone. Six male subjects were recruited (average age (+/-SD): 22 +/- 2 y).

Validity, reliability and sensitivity of measures of sporting performance.

Performance testing is one of the most common and important measures used in sports science and physiology. Performance tests allow for a controlled simulation of sports and exercise performance for research or applied science purposes. There are three factors that contribute to a good performance test: (i) validity; (ii) reliability; and (iii) sensitivity.

Superior endurance performance with ingestion of multiple transportable carbohydrates.

Introduction: The aim of the present study was to investigate the effect of ingesting a glucose plus fructose drink compared with a glucose-only drink (both delivering carbohydrate at a rate of 1.8 g.min(-1)) and a water placebo on endurance performance.

Reliability of a cycling time trial in a glycogen-depleted state.

The aim of this study was to investigate the reliability of a protocol designed to simulate endurance performance in events of long duration (approximately 5 h) where endogenous carbohydrate stores are low. Seven male subjects were recruited (age 27 +/- 7 years, VO(2max) 66 +/- 5 ml/kg/min, W (max) 367 +/- 42 W). The subjects underwent three trials to determine the reliability of the protocol.

Pseudoephedrine enhances performance in 1500-m runners.

Unlabelled: Pseudoephedrine is an over-the-counter drug to relieve nasal and sinus congestion. Although it has been suggested that pseudoephedrine could be a stimulant and ergogenic aid, pseudoephedrine was recently removed from the banned substance list by the International Olympic Committee and placed on the monitoring program (from January 2004). It was felt that evidence was lacking for an ergogenic effect, although few studies have investigated the effects of pseudoephedrine on exercise performance.

Exogenous carbohydrate oxidation rates are elevated after combined ingestion of glucose and fructose during exercise in the heat.

The first purpose of this study was to investigate whether a glucose (GLU)+fructose (FRUC) beverage would result in a higher exogenous carbohydrate (CHO) oxidation rate and a higher fluid availability during exercise in the heat compared with an isoenergetic GLU beverage. A second aim of the study was to examine whether ingestion of GLU at a rate of 1.5 g/min during exercise in the heat would lead to a reduced muscle glycogen oxidation rate compared with ingestion of water (WAT).