When you exercise in a thermally neutral environment or in a hot environment, the metabolic heat load places a considerable burden on the mechanisms that control body temperature. Let's look at some of the physiological changes that occur in response to exercise while the body is exposed to heat stress. For the purpose of this exercise, let's compare the responses of a dehydrated athlete to a well-hydrated athlete. Let's assume that the athlete is exercising at a steady, submaximal intensity in a warm environment. ldentify which physiological responses to heat stress increase, decrease, or stay the same.
1. End-diastolic volume
2. Demand for blood flow and oxygen to muscles
3. Working muscle blood flow
4. Body temperature
5. Cardiac output