Written by Alan Moses
A reporter for HealthDay
MONDAY, Nov. 21, 2022 (HealthDay News) — Regular exercise has long been touted as a great way to keep your heart healthy, but could a morning workout be more beneficial than an evening visit to the gym?
For women in their 40s and older, the answer appears to be yes, new research suggests.
“First of all, I would like to emphasize that physical activity or doing some kind of exercise is useful at any time of the day,” said study author Gali Albalak, a doctoral student in the Department of Internal Medicine at Leiden University Medical Center in the Netherlands.
Indeed, most health guidelines ignore the role of time altogether, Albalak said, choosing to focus mostly on “exactly how often, how long, and at what intensity we should be active” to get the most heart-healthy benefits.
But Albalak’s research focused on the intricacies of the 24-hour wake-sleep cycle — what scientists call the circadian rhythm. She wanted to know if there might be “a possible additional health benefit to physical activity.” when people choose to exercise.
To find out, she and her colleagues turned to data previously collected by the UK Biobank, which tracked the physical activity patterns and heart health of nearly 87,000 men and women.
Participants ranged in age from 42 to 78, and nearly 60% were women.
All were healthy when fitted with an activity tracker that monitored exercise patterns over the course of a week.
In turn, the condition of the heart was monitored for an average of six years. During that time, approximately 2,900 participants developed heart disease, and about 800 had a stroke.
Comparing cardiac “incidents” and exercise time, the researchers determined that women who exercised mostly in the “late morning” — that is, between about 8 and 11 a.m. — faced the lowest risk of heart attack or stroke.
Compared with women who were most active later in the day, those who were most active early or late in the morning had a 22-24% lower risk of heart disease. And for those who mostly exercised late in the morning, the relative risk of stroke decreased by 35%.
However, the increased benefit of morning exercise was not seen among men.
why? “We didn’t find any clear theory that could explain this finding,” Albalak said, adding that more research is needed.
She also stressed that her team’s findings were based on an observational analysis of exercise rather than a controlled test of exercise time. This means that while decisions about when to exercise do have an impact on heart health, it’s premature to draw any conclusions. reasons the risk of increasing or decreasing the heart.
Albalak also stressed that she and her team “are aware that there are social issues that prevent a large group of people from being physically active in the morning.”
However, the results suggest that “if you have an opportunity to be active in the morning – for example, on a day off, or by changing your daily commute – it can’t hurt to try to start your day with some activity.”
One expert found the findings interesting, surprising and somewhat mysterious.
“An easy explanation doesn’t come to mind,” admitted Lona Sandon, program director of clinical nutrition at the School of Health Professionals at UT Southwestern Medical Center in Dallas.
But to get a better understanding of what’s going on, Sandon suggested it might be useful to gather information about the participants’ eating patterns going forward.
“We know from nutrition research that you feel fuller when you eat in the morning than when you eat in the evening,” she said. This may indicate a difference in how the metabolism works in the morning and in the evening.
This may mean that “the timing of meals before physical activity may affect metabolism and nutrient storage, which may further affect cardiovascular risk,” Sandon added.
It’s also possible that morning workouts reduce stress hormones to a greater extent than evening workouts. If so, it can also affect heart health over time.
In any case, Sandan echoed Albalac’s admission that “any exercise is better than no exercise.”
So, “exercise at a time of day when you know you’ll be able to stick to your regular schedule,” she said. “And if you can, take a morning physical activity break instead of a coffee break.”
The report was published on November 14 European Journal of Preventive Cardiology.
Johns Hopkins Medicine has more information on exercise and heart health.
SOURCES: Hali Albalak, PhD, Department of Internal Medicine, Department of Geriatrics and Gerontology, Leiden University Medical Center, The Netherlands; Lona Sandon, Ph.D., M.D., Program Director and Associate Professor, Department of Clinical Nutrition, School of Health Professions, UT Southwestern Medical Center, Dallas; European Journal of Preventive Cardiology, November 14, 2022