Fitness and Exercise as Linked to Overall Stress and Physiological Stress Responses

Exercise has been shown to correlate with physiological response reduction to stress, but there is not much research on short-term stress hormones for this response. For this thesis, I hypothesized that exercise and fitness levels would be negatively correlated with perceived stress and with physiological stress from a standard stressor. In the study, undergraduate college participants answered questions about their chronic stress, current mood, past week’s physical activity (amount and intensity), perceived physical fitness, and demographic characteristics. In addition, participants engaged in a social stress task, where they were given five minutes to prepare a five minute speech with no notice or resources that they then gave in front of peer who they were told was analyzing and recording them. Then they were asked to do a mental math task aloud for five minutes. To measure physiological reactions, participants’ blood pressure, heart rate, and salivary amylase levels were assessed at baseline, immediately after the stressor, ten minutes after the stressor, and thirty minutes after the stressor. Participants who had a higher perceived fitness reported significantly lower stress on a measure of everyday student hassles. Participants were found to be significantly emotionally stressed from the stress-inducing task. The correlations between exercise engagement, perceived fitness, and amount of induced stress were analyzed, but participants who exercised more or had higher perceived fitness did not show significantly lower amylase, heart rate, or diastolic blood pressure responses to the stressful task. Participants who exercised more did show significantly higher systolic blood pressure than participants who did not exercise as much, which prompts a call for further research. When comparing those high and low in perceived fitness, there was a pattern in which the amylase response was lower in the high-fitness groups; however these results should be interpreted with caution. These findings reinforce the theory that exercise reduces stress, but questions remain as to the effect of exercise and fitness on the physical response.