It's well recognised that physical activity is a key step in maintaining good health and reducing personal health risks.  Physical activity is often referred to as one of the four "pillars of health" (the others being nutrition, sleep and managing pressure).  The World Health Organisation (WHO) has just published a raft of evidence outlining the type, frequency and duration of physical activity levels suggested to help avoid serious health problems.

Physical inactivity has been recorded by the WHO as the fourth leading risk factor for global mortality, causing 6% of deaths globally.  This follows high blood pressure (13%), tobacco use (9%) and high blood glucose (6%).  (Source: Global health risks: mortality and burden of disease attributable to selected major risks.  World Health Organisation, Geneva, 2009).

Physical inactivity is also estimated to be the principal cause for approximately 21-25% of breast and colon cancer burden, 27% of diabetes and approximately 30% of ischaemic heart disease burden.  In addition, the WHO also claim non-communicable diseases now account for nearly half of the overall global burden of disease.  It is estimated that of every 10 deaths, 6 are attributable to non-communicable conditions. (Source: The global burden of disease: 2004 update.  World Health Organisation, Geneva, 2008).

In a first step towards planning to reduce the health risks associated with inactivity, the WHO has just published "Global Recommendations on Physical Activity for Health", with the aim of providing national policy makers with guidance on the dose-response relationship between the frequency, duration, intensity, type and total amount of physical activity needed for the prevention of non-communicable diseases.

That means the WHO have worked out the optimum amounts of exercise to reduce health risks.  Although there's lots of detail in the full report, the guidance for adults is to do at least 150 minutes of moderate-intensity aerobic physical activity throughout the week, or at least 75 minutes of vigorous-intensity aerobic physical activity throughout the week, or an equivalent combination of the two.

The guidance also suggests aerobic activity should be performed in bouts of at least 10 minutes duration and for additional health benefits, adults should increase their moderate-intensity aerobic physical activity to 300 minutes per week, or engage in 150 minutes of vigorous-intensity aerobic physical (or an equivalent combination).  Muscle-strengthening activities are apparently best done involving major muscle groups on 2 or more days a week.

Although nearly all health guidance in the UK has been based around these kinds of activity levels of many years, the WHO report is a milestone in compiling all the different sources of evidence and basing appropriate guidance on sound clinical studies.  It's also a good indication of how leading health organisations want to encourage people to take personal responsibility for reducing their own health risks, which is likely to become even more important if health resources are constrained by government spending plans in the future.

Sources:

Global health risks: mortality and burden of disease attributable to selected major risks.
Geneva, World Health Organisation, 2009

The global burden of disease: 2004 update. World Health Organisation, Geneva, 2008