Medicine and science in sports and exercise
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Med Sci Sports Exerc · Mar 2001
The influence of recovery posture on post-exercise hypotension in normotensive men.
Postexercise hypotension may be the result of an impaired vasoconstrictor response. This hypothesis was investigated by examining the central and peripheral hemodynamic responses during supine and seated recovery after maximal upright exercise. ⋯ The lower peripheral resistance in the supine compared with seated recovery position suggests there is potential for greater vasoconstriction, although this is not evoked to increase blood pressure. This further suggests that the arterial baroreceptor reflex is reset to a lower operating pressure after exercise.
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Med Sci Sports Exerc · Dec 2000
GuidelineJoint Position Statement: nutrition and athletic performance. American College of Sports Medicine, American Dietetic Association, and Dietitians of Canada.
It is the position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine that physical activity, athletic performance, and recovery from exercise are enhanced by optimal nutrition. These organizations recommend appropriate selection of food and fluids, timing of intake, and supplement choices for optimal health and exercise performance. This position paper reviews the current scientific data related to the energy needs of athletes, assessment of body composition, strategies for weight change, the nutrient and fluid needs of athletes, special nutrient needs during training, the use of supplements and nutritional ergogenic aids, and the nutrition recommendations for vegetarian athletes. ⋯ However, supplements may be required by athletes who restrict energy intake, use severe weight-loss practices, eliminate one or more food groups from their diet, or consume high-carbohydrate diets with low micronutrient density. Nutritional ergogenic aids should be used with caution, and only after careful evaluation of the product for safety, efficacy, potency, and whether or not it is a banned or illegal substance. Nutrition advice, by a qualified nutrition expert, should only be provided after carefully reviewing the athlete's health, diet, supplement and drug use, and energy requirements.
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Med Sci Sports Exerc · Oct 2000
Randomized Controlled Trial Clinical Trial Controlled Clinical TrialUtilizing exercise to affect the symptomology of fibromyalgia: a pilot study.
Fibromyalgia (FM), a rheumatological disorder of unknown origin, is characterized by both physical and psychological symptoms. Although inconclusive results have been reported for most treatment modalities, exercise appears to have universal support for decreasing the myriad of symptoms associated with FM. Weaknesses in the literature, however, prevent conclusive statements regarding exercise prescription and concomitant impact on FM symptomology. ⋯ A larger number of subjects and direct supervision of the training program to increase compliance is necessary to clarify the effects of a walking program on the manifestations of FM. Results indicate that intensity of the walking program is an important consideration. Individuals with FM can adhere to low-intensity walking programs two to three times per week, possibly reducing FM impact on daily activities.
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Med Sci Sports Exerc · Sep 2000
Comparative StudyA comparative evaluation of three accelerometry-based physical activity monitors.
Accelerometry-based activity monitors offer promise for the assessment of free-living physical activity. They provide an objective record of frequency, intensity, and duration of physical activity with minimal burden on participants. The purpose of this study was to evaluate the absolute and relative validity of three contemporary activity monitors (Computer Science and Applications, Inc. [CSA], Tritrac, and Biotrainer) under both laboratory and field conditions. ⋯ The observed differences among the monitors were attributed primarily to differences in the accuracy of the calibration equations rather than to the monitors themselves. Further research is needed to better understand how to use these devices for field-based assessments of physical activity.
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Med Sci Sports Exerc · May 2000
Comparative StudyDetermination of circulating hemoglobin mass and related quantities by using capillary blood.
A standardized carbon monoxide (CO) rebreathing procedure with measurements of CO-hemoglobin, hemoglobin concentration ([Hb]), and hematocrit (Hct) enables to determine total Hb mass (Hb(tot)), blood, erythrocyte, and plasma volume (BV, EV, and PV). These calculations are normally based on venous blood samples. However, micromethods also allow determinations from capillary blood. ⋯ Calculation of Hb(tot) using capillary blood is as accurate and reliable as using venous blood.