The American College of Sports Medicine recommends that adults exercise for at least 150 minutes per week to maintain good health. The organization supports breaking up that time however the individual chooses. Now a new study suggests that multiple short workouts might provide better health benefits than a single longer session. Published last year in the journal Medicine & Science in Sports & Exercise, the study compared the effects of different exercise bouts on blood pressure over a 24-hour period. Scientists recruited 11 hypertensive individuals around 28 years old. Each was randomly selected to participate in one of the following protocols: one 30-minute continuous exercise session; three 10-minute exercise sessions evenly spaced throughout the day; or no exercise (the control group). The mode of exercise in each case was treadmill walking at 75%–79% of heart rate maximum – moderately high intensity. Subjects were monitored with an automated ambulatory blood pressure device for 24 hours.
Both protocols were associated with lower systolic blood pressure than the control option during daytime and evening hours (1:00–11:00 pm). However, subjects who completed the three short bouts also had lower blood pressure overnight (11:00 pm–8:00 am) and the following morning (8:00 am–noon). This was not the case of the single-bout group. This adds to the strengthening argument for discontinuous/fractionated exercise. We already know that many individuals, especially those new to physical activity, are more inclined to adhere to an exercise program when they break up their workouts into smaller chunks – discontinuous exercise can be more manageable physically for new exercisers, as well as in terms of time management. For those who are starting an exercise program to address hypertension, here is another reason to adopt this type of protocol.