Cardiovascular Responses to Heat Waves in the Elderly

Inclusion Criteria: * Healthy male and female individuals * 18-35 years or 65+ years of age * Free of any underlying moderate to serious medical conditions Exclusion Criteria: * Known heart disease; other chronic medical conditions requiring regular medical therapy including cancer, diabetes, neurological diseases, uncontrolled hypertension, and uncontrolled hypercholesterolemia. * Taking of any medications (such as beta blockers and non-dihydropyridine calcium channel blockers) that have known influences on either cardiac function or sweating responses. * Abnormalities detected on routine screening. * Individuals who participate in a structured aerobic exercise training program at moderate to high intensities. * Current smokers, as well as individuals who regularly smoked within the past 3 years. * Body mass index of greater than 30 kg/m\^2 * Pregnant individuals