Neurovascular mechanisms cause the decrease in BP levels, results from a study of 23 participants in Brazil show.
Elderly individuals who exercise in the evening have a greater decrease in blood pressure (BP) compared with those who exercise in the morning, according to the results of a study presented at the American Physiology Summit, the annual meeting of the American Physiological Society (APS), in Long Beach, California.
Neurovascular mechanisms caused the decrease in BP levels, according to investigators.
“Elderly patients or those with resistant hypertension or obesity don’t always experience as much blood pressure benefit from exercise as other groups,” Leandro Brito, PhD, a postdoctoral fellow at the Oregon Health & Science University, said in a statement. “For these patients, finding a more beneficial time to exercise may reduce their need for medication or help it work better.”
The study, which was conducted at the University of São Paulo in Brazil, included 23 older adults with hypertension who were taking prescribed BP medication for at least 4 months.
The individuals exercised 3 times a week for 10 weeks by cycling on a stationary bike, with 1 group exercising between 7 a.m. and 10 a.m. and 1 exercising between 5 p.m. and 8 p.m.
“The purpose of our research was to understand the role of the neural mechanism that control people’s arterial tonus in the blood pressure lowering effect induced by aerobic exercise training conducted in the evening versus in the morning,” Brito said in a video interview with APS.
“We have 2 main findings in the study, actually. First is that aerobic training performed in the evening was greater than morning to decrease blood pressure in elderly patients with hypertension. In the second finding, we found that the neural mechanisms that control people’s arterial tonus may at least partially explain the greater blood pressure decrease when those patients trained in the evening,” Brito said.
Investigators found that though the diastolic BP decrease was similar in both groups, the systolic BP only decreased in the evening.
Additionally, they measured the autonomic nervous system functions that regulate involuntary processes and control BP. The investigators found that the improvement in the neural responses to changes in BP, known as the arterial tonus, was responsible for the benefits of evening exercise.
“Although any exercise is always better than no exercise, people who need to achieve faster regularization of blood pressure or who don’t see benefits from exercise might want to try working out in the evening,” Brito said. “These findings replicate what we found in a previous study of middle-aged men with hypertension on blood pressure medicine, but now we understand the neural mechanisms that contribute.”
Investigators will continue to look into the body’s “biological clock” and how this could contribute to the findings.
Trying to lower blood pressure? Evening exercise might be best. American Physiological Society. News release. April 18, 2023. Accessed April 13, 2023. Email.