One healthy, female endurance athlete (BW = 64 kg) will perform two bouts of prolonged running exercise (90 min at 175 m/min) in an environmental chamber on 2 separate days under different conditions: 1) at 21 C and 2) at 34 C.; each trial at 50% RH The subject has a maximal VO2 of 3.92 L/min. The subject will not consume any fluids during either trial.

If there are differences in the outcome variables between Trial 1 and Trial 2, address what factor(s) contribute to these differences.

Given the data in Trial 2 (34 C), at what point during exercise (i.e. if exercise continued), would the exercise become dangerous?

Explain your predicted BP (including systolic and diastolic) responses. If you predicted differences between trials, what factor(s) could explain these differences?

What could explain the unchanged VO2 from Trial 1 to Trial 2, even though Q is higher in Trial 2 vs. Trial 1?

Would you predict there to be differences in skin blood flow or muscle perfusion during the two trials?

What procedures/strategies may be used to minimize differences in thermoregulatory and cardiovascular outcomes between the two trials (assuming you cannot control the weather)?