SOLNA, Sweden — Morning gym-goers reap more rewards and burn more calories, a new study explains. Through an experiment involving mice, researchers in Sweden say the animals have a higher metabolism if they exercise earlier in the day. Moreover, scientists add this is also the case in humans.
Biological processes work differently depending on the time of day, due to each cell’s circadian rhythm — the system which regulates the sleep-wake cycle over 24 hours. Researchers at Karolinska Institutet set out to discover the impact on our workouts. At two points in the day, experts set mice on a high-intensity workout and studied their adipose tissue afterwards.
Joined by a team from University of Copenhagen, the researchers marked an early active phase and early rest phase, corresponding to a late morning and late evening gym session in humans. They looked at which genes were active in adipose tissue, otherwise known as body fat, and discovered those involved with boosting the metabolism were more abundant in the morning slot — regardless of how much food they ate. Morning workout genes broke down fat by producing heat and mitochondria in the adipose tissue.
“Our results suggest that late morning exercise could be more effective than late evening exercise in terms of boosting the metabolism and the burning of fat, and if this is the case, they could prove of value to people who are overweight,” says Professor Juleen Zierath from the Department of Molecular Medicine and Surgery and the Department of Physiology and Pharmacology at the Karolinska Institutet in a media release.
“The right timing seems to be important to the body’s energy balance and to improving the health benefits of exercise, but more studies are needed to draw any reliable conclusions about the relevance of our findings to humans,” Prof. Zierath concludes.
Mice have been a long-established model for human physiology and metabolism. However, the researchers say that their comparison, published in the Proceedings of the National Academy of Sciences is limited by the fact mice are nocturnal creatures.
What time should you start working out?
A recent study by researchers from the European Society of Cardiology finds morning physical activity appears to provide the biggest boost to heart health, producing the lowest risk of heart disease and stroke. The researchers found that activity between 8 a.m. and 11 a.m. yielded the lowest risk of both events.
According to the study in 2019, older adults who regularly partake in moderate-intensity workouts in the morning enjoy the benefits of a sharper brain during the day.
Is there any benefit to working out at night?
While studies find a number of different health benefits by getting an early start at the gym, not everyone has the time to do this. For those who have to work out later in the day, studies show it’s still worthwhile.
In fact, night owls who like to go for a brisk walk, bike ride, or jog later in the day are less prone to diabetes. Scientists in the Netherlands say engaging in regular exercise late in the day improves blood glucose control among older adults. A study of 775 Dutch men and women found those who were physically active in the afternoon or evening were less likely to develop the disease in comparison to those working out in the morning.
South West News Service writer Pol Allingham contributed to this report.