ABSTRACT
“Cramping” of leg muscles during sports competition is a common occurrence and, although not serious, such muscle spasms are both painful and temporarily disabling. Despite their frequency, the cause of exercise-associated muscle cramps remains uncertain, and, consequently, the means by which they might best be prevented is not clear. This section of the chapter outlines two prevalent theories on the pathogenesis of cramps: a) dehydration and excessive salt loss via sweating in hot ambient conditions, and b) muscular fatigue triggering abnormalities in contraction/relaxation properties of muscle. To many, the loud shriek or grunt emitted by many professional tennis players when striking the ball is simply an auditory annoyance, but others have insisted that such noise serves as an unfair distraction. This section of the chapter examines the research addressing the influence of these noises on tennis performance. Evidence does exist that such shrieks may prove to be distracting and detrimental to the opponent. As well, research findings suggest that shrieking may serve to increase the force of the tennis swing. World records in endurance athletic events have steadily improved over the past century. Such advances might be accounted for by improved training regimens, advances in equipment and techniques, improved nutritional practices, and rule and measurement changes. It should be expected, though, that a physiological ceiling exists which provides a biological limit to such performance. Some evidence exists that such top performance times are plateauing in recent years for many events, and in some cases a ceiling of performance may already have been achieved.
