For women, morning workouts were found to reduce belly fat and improve blood pressure more than late-night workouts. Evening exercise also amplified the benefits of strength training, but more so for women.
The study of exercise timing is part of the rapidly developing science of chronobiology, which focuses on how the body clock influences nearly every aspect of physiology.
The human body, like other mammals, plants, reptiles and insects, operates on an innate 24-hour clock. circadian rhythmthe master clock system in our brains sends and receives biochemical signals that work in concert with molecular clocks within our cells to orchestrate a tremendous symphony of biological processes.
This rhythm responds to signals from the outside world, especially day and night, but also to eating, sleeping and exercise.
Recently research in mice Large groups of rodents were allowed to run on exercise wheels at different times of the day. Studies have shown that an animal’s heart rate, fat burning, gene expression, and body weight can vary significantly depending on when they exercise, even if the exercise itself is the same.
However, human studies on exercise timing are more contradictory. Some shows people burn excess fat, lose more weight By exercising early in the morning, especially before breakfast, others suggest greater health benefits from the afternoon or afternoon. night training.
However, most of these studies were small and included only men with metabolic diseases such as type 2 diabetes, hypertension and obesity. So little is known about the optimal timing of exercise for healthy men, and even less about the optimal timing for women.
A Real Study of Exercise Timing
The study, published in Frontiers in Physiology in May, is designed to reflect real-life demographics, said Dr. Stuart, director of the Institute for Human Nutrition, Performance and Metabolism at Skidmore College in Saratoga Springs, New York. said Paul Arciero, lead author of the study.
All volunteers self-identified as either male or female, and more than half of the 56 participants were female. Also, although all were healthy and physically active, they were not athletes.
Researchers tested the health, strength, and fitness of the volunteers and randomly divided them into two equal groups of men and women. In one group, he was instructed to exercise between 6am and 8am four times a week. The other group was instructed to exercise in the evening between 6:30 pm and 8:30 pm.
Each group participated in the same workout. Once a week they lifted weights. The next day, they did approximately 35 minutes of interval training (running, swimming, cycling, resting, and repeating as hard as possible for about 1 minute). On other days, I did yoga and pilates. They ended the week with about an hour of running, biking, or other aerobic exercise.
The group remained on this routine for 12 weeks and then returned to the lab for retesting.
everyone who participated in the study Slimmer, faster, healthier, stronger, healthier, more flexible, regardless of whether you worked out early or late.
Want to lose belly fat? Or get stronger?
However, there were relevant differences between the groups based on the time they exercised.
- Women are more likely to burn fat in the morning. Female early exercisers lost, on average, about 3% more body fat than evening exercisers. Much of the loss is due to the waistline. Women who exercised in the morning had about 7% less abdominal fat than women who exercised in the evening. (Volunteers’ total body weight did not decrease because they gained muscle when they lost fat.)
- Morning exercise also significantly lowered blood pressure in female exercisers more than the same exercise in the evening.
- On the other hand, evening exercise by women amplified strength gains. I was.
- For men, evening exercise was the clear winner when it came to health. Those who exercised at night had significantly lower cholesterol levels, but surprisingly, those who exercised in the morning had slightly higher cholesterol levels. Exercise at night also promoted fat burning in men. By the end of the study, the bodies of male evening exercisers were burning approximately 28% more fat during exercise than at the start, a change that may facilitate body fat loss. fat burning increased only slightly.
- However, it was always a good time for men to improve their strength and fitness. , sit-ups, push-ups, and other peak intensities by about the same amount.
What these results really mean is that women with specific health or fitness goals may want to tweak their workout timings. If you’re a woman who wants to, consider training in the morning. If your goal is strength, training in the evening may be more effective.
For men, exercising early in the morning or later in the day seems to be comparable to strength and fitness, but evening exercise may have special health benefits, says Arciero.
“We are just getting started when it comes to individualizing the optimal time of day to exercise,” says John Hawley, director of the Exercise Nutrition Research Program at the Australian Catholic University in Melbourne, Australia. . learned exercise Metabolism and timing were included but were not involved in this study.
He noted that the new study did not control women’s menstrual cycles or track people’s chronotypes. Nor did they investigate why the women responded differently.Arciero suspects hormonal or other cellular and genetic influences, and plans follow-up studies to learn more, he said. rice field.
For now, the key takeaway from this research is that timing may fine-tune what you get from exercise.
Have a fitness question? e-mail [email protected] I may answer your question in a future column.
