Wednesday October 10 2007
Break a sweat - it's better for you.
A study has found that most Britons are under the false impression that moderate activity, such as walking, is better for your health than vigorous exercise such as running. “Run, don’t walk, if you want to maximise your chances of living a long and healthy life – and don’t be misled by what the Government tells you”, said The Independent.
BBC News reports that the study suggests that this has been a result of “’misleading’ government guidelines”. It quotes the lead author of the study as saying “It's extremely worrying that British adults now believe that a brief stroll and a bit of gardening is enough to make them fit and healthy. Brisk walking offers some health benefits, but jogging, running and other vigorous activities offer maximal protection from disease.”
These stories are based on a study reporting the results from an internet survey. It cannot be determined from this study whether the participants’ beliefs about exercise have come about because of the current British physical activity guidelines. It is also unclear whether people’s levels of activity would change if they knew that vigorous exercise was more beneficial. It is important to remember, although vigorous activity may offer the greatest health benefits, moderate exercise is better than no exercise at all.
Where did the story come from?
Drs Gary O’Donovan from the University of Exeter and Rob Shave from Brunel University carried out this research. The Sports Marketing Research Trust funded the study and it was published in the peer-reviewed medical journal Preventive Medicine.
What kind of scientific study was this?
This was a cross sectional study looking at the attitudes of British people to exercise between March and May 2006. It has been suggested that because moderate activity has been recommended for adults in Britain since 1995, this has led people to believe that moderate activity holds the greatest health benefits.
The researchers commissioned an independent research agency to conduct the surveys. The agency surveyed a panel of people across Britain via the internet; these people were selected to be representative of the population in terms of age, sex, income, and geographical location. Participants were asked a series of questions about their perception of the benefits of physical activity, including whether they thought there were health benefits to be gained from regular physical activity, what types of activity gave the most health benefits (gentle, moderate, or vigorous), and what type of activity was currently recommended for adults. Gentle activity includes housework or shopping, moderate activity includes brisk walking, and vigorous activity includes team sports, jogging and running. In all 1,191 adults aged 16–65 years old took part in the survey.
What were the results of the study?
About nine out of 10 people thought that regular physical activity gave meaningful health benefits. The majority of people surveyed (about five in 10 men and about seven in 10 women) thought that moderate activity offered the greatest benefits. People in older age groups (46–65 years) were more likely to hold this belief than those in younger age groups. About eight out of 10 people reported that moderate activity was recommended for adults, and again, people in older age groups were more likely to know this.
What interpretations did the researchers draw from these results?
The researchers concluded that policymakers should clarify that vigorous activity has more health benefits than moderate activity, because many Britons incorrectly think that moderate activity is more beneficial.
What does the NHS Knowledge Service make of this study?
This survey gives us an indication about the prevailing beliefs about exercise in Britain in 2006. The study does have some limitations, which include the following:
- Although the research agency’s panel was selected to be nationally representative, only 20–35% of the panel answered the current survey. It is possible that their answers may not be representative of the beliefs of the population as a whole, especially as the survey was relatively small compared to the overall population of the UK, which is estimated to be about 60 million.
- The authors of the paper correctly state that this type of cross sectional data cannot show whether these beliefs have arisen because of the recommendations for moderate activity. This is because we do not know whether these beliefs were held before the recommendations were introduced, or only came about after.
It is important to keep in mind that vigorous exercise may not be appropriate for people with serious medical conditions, and that moderate exercise is better than no exercise at all. There may be a greater risk of injuries from vigorous exercise than from moderate exercise, so participants should take sensible precautions such wearing appropriate clothing and protective gear, warming up and down, and seeking advice from healthcare professionals if needed.
Sir Muir Gray adds...
They may believe it, but they still don’t do it. If another 10 million people walked 3,000 extra, vital steps a day, the health of the nation would be greatly improved and they can take up running after that. The ideal should not be the enemy of the good.