Athletes who are properly fueled and hydrated before, during, and after exercise can improve training, increase performance, and decrease fatigue. Many commercial products are marketed to athletes and are designed to be consumed at specific periods: before, during, and after exercise. Are these products really necessary? This article reviews the research on nutrition support for [...]
To determine if athletes' muscle mass affects the usefulness of urine specific gravity (U(sg)) as a hydration index. Nine rugby players and nine endurance runners differing in the amount of muscle mass (42 +/- 6 vs. 32 +/- 3 kg, respectively; P = 0.0002) were recruited. At waking during six consecutive days, urine was collected [...]
To determine how the sodium content of ingested fluids affects drinking and the restoration of the body fluid compartments after dehydration, we studied six subjects during 4 h of recovery from 90-110 min of a heat [36 degrees C, less than 30% relative humidity (rh)] and exercise (40% maximal aerobic power) exposure, which caused body [...]
This paper reviews the literature, describes and discusses methods by which whole body hydration status can be determined in humans. A method of determining whether or not an individual is hypohydrated is of particular significance in an exercise situation as even moderate levels of hypohydration have a negative impact on exercise performance. Inspection of the published literature [...]
Euhydrated and dehydrated subjects exercised in a hot and a cold environment with our aim to identify factors that relate to reductions in stroke volume (SV). We hypothesized that reductions in SV with heat stress are related to the interaction of several factors rather than the effect of elevated skin blood flow. Eight male endurance-trained cyclists [maximal O(2) consumption (VO(2 max)) 4.5 [...]
BACKGROUND: Well-recognized markers for static (one time) or dynamic (monitoring over time) dehydration assessment have not been rigorously tested for their usefulness in clinical, military, and sports medicine communities. OBJECTIVE: This study evaluated the components of biological variation and the accuracy of potential markers in plasma, urine, saliva, and body mass (B(m)) for static and dynamic dehydration assessment. DESIGN: We studied 18 healthy volunteers (13 men and 5 [...]
As the number of youth sports participants continues to rise over the past decade, so too have sports related injuries and emergency department visits. With low levels of oversight and regulation observed in youth sports, the responsibility for safety education of coaches, parents, law makers, organizations and institutions falls largely on the sports medicine practitioner. [...]
"BACKGROUND: Muscle contraction during short intervals of intense exercise causes oxidative stress, which can play a role in the development of overtraining symptoms, including increased fatigue, resulting in muscle microinjury or inflammation. Recently it has been said that hydrogen can function as antioxidant, so we investigated the effect of hydrogen-rich water (HW) on oxidative stress [...]
Objectives: to examine current practice with regard to hydration in acute stroke (part 1) to identify problem areas, to develop, implement and evaluate an intervention package (part 2). Design: prospective, repeated measures, between subjects Setting: a district general hospital. Participants: consecutive admissions with an acute stroke. Part 1 involved 30 patients, 14 of whom were [...]