New research shows a little goes a long way

We all know we should be doing 30 minutes of exercise most days but what if we can’t manage that much – or simply don’t have time?

A new study in the British Journal of Sports Medicine is the first we’ve heard of that acknowledges the fact that many over-60s cannot meet the recommended 150 minutes of exercise per week mandated by health authorities, and set out to discover if any regular amount of activity below this level was associated with greater longevity in this age group.

The researchers found that just a little moderate to vigorous physical activity―well below the recommended amount―every week still seems to curb the risk of death, although the more you can squeeze in, the better off you are.

They trawled through research databases that assessed the risk of death according to weekly physical activity for those aged 60 and above and looked at the associated risk of death for four categories of weekly physical activity:  inactive, low, medium, and high.

Physical activity was measured in Metabolic Equivalent of Task (MET) minutes, which express the amount of energy (calories) expended per minute of physical activity.

One MET minute is equal to the energy equivalent of just sitting, and how many MET minutes an individual clocks up every week depends on the intensity of physical activity s/he does. For example, moderate intensity activity ranges between 3 and 5.9 MET minutes while vigorous intensity activity is classified as 6 or more.

The current recommendation is for a tally of between 500 and 1000 MET minutes every week.

Pooled analysis of the data showed that clocking up less than 500 weekly MET minutes of physical activity was still associated with a 22 per cent lowered risk of death compared with those who were inactive.

The more physical activity an individual engaged in, the greater the health benefit, reaching a 28 per cent lower risk of death for those fulfilling the recommended weekly tally of MET minutes, while more than 1000 MET minutes was associated with a 35 per cent lower risk.

Unsurprisingly, the greatest benefit seemed to be among those who went from doing nothing or only a minimal amount of physical activity to doing more.

Much of the health benefit seemed to be for a reduced risk of dying from heart disease/stroke, while the reduction in deaths from all causes was considerably greater in older women than it was in older men.

The researchers found that a weekly tally of 250 MET minutes, which corresponds to 75 minutes of moderate to vigorous physical activity―or 15 minutes a day―was associated with health benefits, prompting the researchers to suggest that this could be “a reasonable target dose”.

“Based on these results, we believe that the target for physical activity in the current recommendations might be too high for older adults and may discourage some of them… The fact that any effort will be worthwhile may help convince those 60 per cent of participants over 60 years of age, who do not practise any regular physical activity, to become active.”

Do you think 15 minutes of exercise a day is a more accessible target? Should the recommendations be changed?