Becoming more physically active makes people feel good and improves health. Most people are convinced about that, but there is now evidence to show that a higher level of total activity in a week could actually cut the risk of specific diseases significantly.
Raising the number of minutes of exercise cuts the risk of diabetes, ischaemic heart disease and stroke, breast and colon cancers.
That is the key pointer from work done by a group of researchers from the United States and Australia who looked at 174 scientific articles published over a 36-year period from 1980 to analyse the association between total activity and at least one of the diseases. They found that a higher level of activity was associated with a lower risk for these conditions.
Every day tasks help The research published by Dr. Mohammad H. Forouzanfar of the University of Washington and his colleagues in the BMJ indicates this: that being far more active than what the World Health Organization (WHO) recommends as the weekly minimum level — 600 Metabolic Equivalent (MET) Minutes — produces substantially improved health gains.
MET is defined as the amount of oxygen consumed when sitting at rest, equivalent to 3.5 ml of O per kilogram of body weight, multiplied by minutes.
Total physical activity could involve gardening, walking up a flight of stairs, riding a bicycle, walking to a bus or train, or doing other chores. The best outcomes are estimated to be available when the METs per week are in the 3,000 to 4,000 range, beyond which they add no particular benefit.
Typically, the researchers say, the weekly 3,000 MET score may be achieved with a combination as follows: Climbing stairs 10 minutes, vacuuming 15 minutes, gardening 20 minutes, running 20 minutes, and walking or cycling for transportation 25 minutes, on a daily basis.
Taking the example of diabetes, it is estimated that for those who have a total activity level of 600 MET minutes/week as recommended by the WHO the reduction in the risk of diabetes was 2 per cent, compared to those who reported no physical activity. A more active person with 3,600 MET minutes/week had a risk reduction of an additional 19 per cent.
Being physically active as a part of the daily routine, however, depends significantly on several policies followed by governments, particularly on urban development. These deal with the availability of good walking spaces and pavements, parks and open spaces, and strong public transport networks.
ananthakrishnan.g@thehindu.co.in
