Resting systolic and diastolic blood pressure in swimmers, runners, and general exercisers

The purpose of this study was to compare the levels of systolic and diastolic blood pressure in men performing regular aerobic exercise (swimming, running, or general exercising). Running, walking and cycling have been shown to provide anti-hypertensive benefits to those suffering fi-om hypertension while swimming has yet to be shown to be a beneficial mode of exercise for blood pressure control. Only one study has been completed using swimming as a training mode. In this study, systolic blood pressure was reduced by 9 mm Hg after a ten week training period, but there was no significant reduction in diastolic or mean arterial blood pressure. Thus there is a need for further information concerning swimming as regular aerobic exercise and its relationship to blood pressure. Resting blood pressure, resting heart rate, height, weight, and percent body fat data were collected on 107 white normotensive male subjects who differed in age and mode of exercise training (swimming, running and general exercising). Repeated measurements were obtained on separate days to assure reliable resting blood pressures. The investigator followed American Heart Association guidelines designed to eliminate erroneous readings of blood pressures. There was a significant effect for age on DBF (p<0.02). Percent Body Fat (p<0.0001) and MET x Min/Week (p<0.0001). In addition, there was a significant effect for mode on SBP (p<0.03), Percent Body Fat (p<0.0001) and MET x Min/Week (p<0.0001). There was a significant interaction between age and mode for MET x Min/Week values (p<0.0001). Contrast statements within each group (age and exercise mode) yielded significantly higher mean SBP in swimmers compared to runners (p<0.008). An age effect for DBP existed in swimmers (p<0.003) but not in runners (p<0.62). Significantly higher mean RHR was found in swimmers (p<0.0001) and runners (p<0.0001) when compared to general exercisers. Swimmers had significantly higher mean Percent Fat when compared to runners (p<0.02). Additionally, when runners were combined with swimmers, they had significantly lower mean Percent Fat (ruimers p<0.0001 and swimmers p<0.0007) compared to general exercisers. The results of this investigation reveal that swimmers have higher resting systolic blood pressure than runners do. Although the swimmers were higher, the level of blood pressure they were at was still well below the hypertensive level. The Older runners and swimmers exhibited resting SBP and DBP well below their average blood pressure for their age. When comparing the percent body fat levels of the exercise groups, it can be seen that percent body fat was much higher in the Older exercise groups and yet they still had low blood pressures when compared to their peers. The benefit of low blood pressure appears to come from exercise then since blood pressure is known to rise with increasing body fat and obesity. It appears safe to recommend swimming as a beneficial mode of exercise for the control and management of hypertension.