Exercise timing and intensity notably influence type 2 diabetes risk in younger adults, study finds

Research presented at the European Association for the Study of Diabetes highlights that moderate-to-vigorous activity, especially later in the day, significantly reduces type 2 diabetes risk among younger adults, with age-related differences in benefits.

A larger amount of moderate-to-vigorous physical activity was linked to a markedly lower risk of type 2 diabetes among younger adults, according to research presented at the European Association for the Study of Diabetes annual meeting in Milan and previously published in Diabetes, Obesity and Metabolism. The analysis of UK Biobank data also suggested that exercising later in the day was associated with lower diabetes risk in younger people, while that timing pattern did not appear in older adults.

The study drew on accelerometer data from 87,975 adults, more than half of them women, with a median age of 63 years. Over a median follow-up of 7.7 years, 2.4% were diagnosed with type 2 diabetes. People who did less than the median amount of moderate-to-vigorous activity had roughly double the risk of diabetes compared with those who did more, and the relationship was strongest in adults younger than 62.7 years. In that younger group, later-day exercise was also associated with a lower risk than early-morning activity, whereas no clear timing effect was seen in older adults.

Qiuyu Feng, a PhD candidate at Leiden University Medical Centre, said the findings underline the value of movement across adulthood, even if the balance of relative and absolute benefit differs by age. Feng noted that younger adults showed the clearest relative reduction in risk, but older adults experienced larger absolute differences in diabetes incidence, meaning activity increases at older ages could still prevent a substantial number of cases at the population level.

The pattern fits with earlier research suggesting that exercise timing may matter as well as total volume. A study reported in 2023 in Diabetologia found that morning and afternoon activity were associated with lower diabetes risk, while evening activity was not. Other research has pointed in a similar direction, including a randomised crossover trial in men with type 2 diabetes that found afternoon high-intensity interval training improved glucose control more than morning sessions. Taken together, the studies suggest that regular activity remains protective at every age, but the size of the benefit may vary according to when people exercise and which risk group they belong to.