Just 10 minutes of light physical activity can lower death risk in older men, according to a study.

Researchers have said that the overall volume of activity is key, rather than the sessions of at least 10 minutes. Current exercise guidelines recommend accumulating at least 150 minutes a week of moderate to vigorous physical activity in bouts lasting 10 or more minutes. But such a pattern is not always easy for older adults to achieve, say the researchers.

To find out if other patterns of activity might still contribute to lowering the risk of death, the researchers drew on data from the British Regional Heart Study. This involved 7735 participants from 24 British towns, who were aged between 40 and 59 when the study stated in 1978-80. In 2010-12, the 3137 survivors were invited for a check-up, which included a physical examination, and questions about their lifestyle, sleeping patterns, and whether they had ever been diagnosed with heart disease.

They were also asked to wear an accelerometer--a portable gadget that continuously tracks the volume and intensity of physical activity--during waking hours for 7 days. Their health was then tracked until death or June 2016, whichever came first. In all, 1566 (50%) men agreed to wear the device, but after excluding those with pre-existing heart disease and those who hadn't worn their accelerometer enough during the 7 days, the final analysis was based on 1181 men, whose average age was 78.

During the monitoring period, which averaged around 5 years, 194 of the men died. The accelerometer findings indicated that total volume of physical activity, from light intensity upwards, was associated with a lower risk of death from any cause. Each additional 30 minutes a day of light intensity activity, such as gentle gardening or taking the dog for a walk, for example, was associated with a 17 percent reduction in the risk of death. This association persisted even after taking account of potentially influential lifestyle factors, such as sedentary time.

Whilst the equivalent reduction in the risk of death was around 33 percent for each additional 30 minutes of moderate to vigorous intensity physical activity a day, the benefits of light intensity activity were large enough to mean that this too might prolong life. And there was no evidence to suggest that clocking up moderate to vigorous activity in bouts of 10 minutes or more was better than accumulating it in shorter bouts. Sporadic bouts of activity were associated with a 41 percent lower risk of death; bouts lasting 10 or more minutes were associated with a 42 percent lower risk.

Sporadic bouts seemed easier to achieve as two thirds (66%) of the men achieved their weekly total of moderate to vigorous physical activity in this way while only 16% managed to do so in bouts of 10 or more minutes. Finally, there was no evidence to suggest that breaking up sitting time was associated with a lower risk of death. The researchers, led by Dr Barbara Jefferis, said: “[The] results suggest that all activities, however modest, are beneficial.

“The finding that [low intensity physical activity] is associated with lower risk of mortality is especially important among older men, as most of their daily physical activity is of light intensity. Furthermore, the pattern of accumulation of physical activity did not appear to alter the associations with mortality, suggesting that it would be beneficial to encourage older men to be active irrespective of bouts.” The study has been published in the British Journal of Sports Medicine.