Chemistry of marathon running
Article Abstract:
Whether a person can become an endurance athlete depends on an inherited trait called slow twitch fibers; if present in large proportions in the muscles, these fibers help muscles produce very efficient force without causing much fatigue. Competitive long distance runners undergo a variety of physiological changes, many of which are beneficial, but there are also some hazards associated with vigorous exercise. The effects of running on the various physiological systems of the body are briefly reviewed. Regular aerobic exercise increases peak performance by promoting metabolic changes that help the athlete to avoid fatigue and to exercise more efficiently. The effects of marathon running on blood cholesterol are not entirely clear, although it appears that total and low-density-lipoprotein (LDL) cholesterol are reduced and high-density-lipoprotein (HDL) cholesterol is increased; all of these changes are thought to reduce the risk of coronary artery disease. Atherosclerosis (fatty plaques accumulating in the arteries) may be reduced by regular exercise. Sudden death and heart attack are rare during strenuous exercise, although participation during the incubation period of a viral illness can exacerbate myocarditis, or inflammation of the heart muscle, a potentially fatal condition. Heat and humidity are hazardous, especially to those who are not used to them. Heat exhaustion and other disorders may follow excessive sweating, and heat stroke can often be fatal. Hormonal changes are frequent, and cause the ''runners high,'' a euphoric state during which pain and fatigue fade. Among women, hormonal changes may cause the menstrual cycles to stop. Changes in the blood chemistry alter the clotting mechanism, possibly contributing to the prevention of ischemic heart disease (reduced blood flow to the heart). The effects on the immune system are variable: moderate exercise has been shown to stimulate it, but exercising to exhaustion compromises immune function. The optimum amount of exercise remains to be determined. (Consumer Summary produced by Reliance Medical Information, Inc.)
Publication Name: Journal of Clinical Pathology
Subject: Health
ISSN: 0021-9746
Year: 1989
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Four-layer bandaging
Article Abstract:
Four-layer bandaging is a valuable therapeutic technique for the treatment of venous ulceration using graduated compression to reduce the pressure on superficial veins and capillaries. It is also useful for treatment of oedema, varicose veins and lymphoedema. The layers are: orthopedic wool; cotton crepe; elastic, conformable compression bandage; and cohesive, elastic compression bandage. Patient and wound assessment procedures are included as well as a list of those patients who cannot use the four-layer bandaging.
Publication Name: Nursing Times
Subject: Health
ISSN: 0954-7762
Year: 1997
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