Morning workouts might make for stronger and longer bones compared with nighttime exercise, according to a study in mice.
Because bone mass starts declining in middle age, it is crucial to keep up with exercise, such as running, jumping and weightlifting, as we age 鈥� these movements put force on our bones and keep them strong, similar to how strength training builds muscle.
at the Huazhong University of Science and Technology in China and her colleagues analysed how workout timing affected bone growth in 79 male mice and 35 female mice. All the mice were 4 weeks old, equivalent to about 11 years old in people.
Advertisement
The researchers divided the mice into seven similarly sized groups. The first six groups moved on a treadmill for 30 minutes a day, each at different times. The control group stayed stationary at various assigned times of the day.
After four weeks, the femurs of mice that exercised soon after waking measured about 3 per cent longer and 25 per cent thicker than those that exercised closer to when they went to sleep. This suggests that morning movement may accelerate bone growth and help maintain bone mass.
But findings in mice do not always translate to people, says at Worcester Polytechnic Institute in Massachusetts. And because these mice were adolescents, it is unclear whether these effects persist with age.
Still, for people who want to optimise exercise鈥檚 bone benefits, these results do hint that morning workouts might be best, says Troy. 鈥淏ut if you can鈥檛 exercise in the morning, any exercise is better than no exercise,鈥� she says. Ultimately, people should focus on the type of exercise they do 鈥� rather than when they do it 鈥� as this has been proven to have a greater impact on bone health. Swimming, for instance, does not bring as much benefit as running.
Nature Metabolism
