Just 15 minutes of daily exercise is enough to lower your risk of death by 22%, a new study has found.
Scientists in France monitored the impact of physical activity on people over the age of 60 and found that even low impact walking was beneficial to their health.
"Age is not an excuse to do no exercise," said Dr Hupin of University Hospital of Saint-Etienne, France.
"It is well established that regular physical activity has a better overall effect on health than any medical treatment. But less than half of older adults achieve the recommended minimum of 150 minutes moderate intensity or 75 minutes vigorous intensity exercise each week."
The authors studied two cohorts. A French cohort of more than 1,000 participants aged 65 in 2001 was followed over a period of 12 years, while an international cohort of more than 122,000 participants aged 60 was followed up after 10 years.
Physical activity was measured in Metabolic Equivalent of Task (MET) minutes per week, which refers to the amount of energy (calories) expended per minute of physical activity.
One MET minute per week is equal to the amount of energy expended just sitting. The number of MET minutes an individual clocks up every week depends on the intensity of physical activity.
For example, moderate intensity activity ranges between 3 and 5.9 MET minutes while vigorous intensity activity is classified as 6 or more MET minutes.
The recommended levels of exercise equate to between 500 and 1000 MET minutes every week.
The authors looked at the associated risk of death for four categories of weekly physical activity in MET minutes, defined as inactive/low (1–499 MET minutes), medium (500–999 MET minutes) or high (more than 1,000 MET minutes).
During the follow up there were 88 (9%) deaths in the French cohort and 18,122 (15%) deaths in the international cohort.
According to the study authors, the risk of death reduced as the amount of exercise increased, but even 15 minutes of walking per day was enough to make a difference.
Compared to those who were inactive, older adults with low, medium and high activity levels had a 22%, 28% and 35% lower risk of death, respectively.
Dr Hupin said: “These two studies show that the more physical activity older adults do, the greater the health benefit.
"The biggest jump in benefit was achieved at the low level of exercise, with the medium and high levels bringing smaller increments of benefit."
He added: "We found that the low level of activity, which is half the recommended amount, was associated with a 22% reduced risk of death in older adults compared with those who were inactive
"This level of activity equates to a 15 minute brisk walk each day."
He concluded by advising older adults to progressively increase physical activity in their lives, rather than dramatically changing their habits over a short period of time.
"Fifteen minutes a day could be a reasonable target for older adults," he said.
"Small increases in physical activity may enable some older adults to incorporate more moderate activity and get closer to the recommended 150 minutes per week."
