More exercise in middle age prolongs life, says long-term studyMarch 5th, 2009 - 1:45 pm ICT by IANS
London, March 5 (IANS) Increased physical activity in middle age prolongs life, though it may take five to 10 years before an effect is seen, concludes a study published Thursday.
Physical activity is beneficial for health, but about half of all middle-aged men in the West do not take part in regular physical activity. It is not yet known whether an increase in exercise later in life reduces death rates.
Researchers in Sweden examined how changes in physical activity levels after middle age influence mortality and compared them with the effect of stopping smoking.
The study, which has been published by the British Medical Journal (BMJ) on its website, involved 2,205 Swedish men aged 50 in 1970-73, who were re-examined at ages 60, 70, 77, and 82 years. Data including body mass index, blood pressure, cholesterol levels, smoking status and alcohol use was recorded at each survey.
At age 50, almost half of the men reported a high level of physical activity, corresponding to at least three hours of recreational sports or heavy gardening a week. Just over a third (36 percent) reported medium activity, corresponding to walks and cycling, and 15 percent were sedentary.
Overall mortality rates were highest among sedentary men and lowest among the most active men.
However, during the first five years of follow-up, the mortality rate was higher in men who had increased their level of physical activity than in men with unchanged high physical activity.
But the number of such deaths was relatively small, so the researchers have not emphasised this finding.
However, after 10 years, the mortality rate in these men was reduced to the same level as men with unchanged high physical activity. This reduction in mortality was similar to the effect of stopping smoking.
After adjusting for other risk factors, the researchers estimate that men who reported high levels of physical activity from age 50 were expected to live 2.3 years longer than sedentary men and 1.1 years longer than men who reported medium levels of physical activity.
Increased physical activity prolongs life among middle aged and older men, though there might be a period of 5-10 years before an effect is seen on total mortality, write the authors.
This effect is the same as stopping smoking, the researchers say.