15 minutes of exercise daily reduces mortality by 14% - and each additional 15 minutes gives 4% additional mortality benefit
Last updated on 28th October 2017
There has been a ripple of media interest - and rightly so - in the recent Lancet article "Minimum amount of physical activity for reduced mortality and extended life expectancy: a prospective cohort study." The article's abstract reads "The health benefits of leisure-time physical activity are well known, but whether less exercise than the recommended 150 min a week can have life expectancy benefits is unclear. We assessed the health benefits of a range of volumes of physical activity in a Taiwanese population. In this prospective cohort study, 416,175 individuals (199,265 men and 216,910 women) participated in a standard medical screening programme in Taiwan between 1996 and 2008, with an average follow-up of 8·05 years (SD 4·21). On the basis of the amount of weekly exercise indicated in a self-administered questionnaire, participants were placed into one of five categories of exercise volumes: inactive, or low, medium, high, or very high activity. We calculated hazard ratios (HR) for mortality risks for every group compared with the inactive group, and calculated life expectancy for every group. Compared with individuals in the inactive group, those in the low-volume activity group, who exercised for an average of 92 min per week (95% CI 71-112) or 15 min a day (SD 1·8), had a 14% reduced risk of all-cause mortality (0·86, 0·81-0·91), and had a 3 year longer life expectancy. Every additional 15 min of daily exercise beyond the minimum amount of 15 min a day further reduced all-cause mortality by 4% (95% CI 2·5-7·0) and all-cancer mortality by 1% (0·3-4·5). These benefits were applicable to all age groups and both sexes, and to those with cardiovascular disease risks."
This publication is another in the ongoing wave of research studies documenting the benefits of exercise across so many aspects of health & wellbeing. Last year Williamson & Pahor wrote in their paper "Evidence regarding the benefits of physical exercise" - "A growing body of evidence has accumulated that has given legs to the hypothesis that the promotion of physical activity may be the most effective prescription that physicians can dispense for the purposes of promoting successful aging." And in 2011 - besides the recent Lancet paper - other articles that have caught my eye include "Adherence to a low-risk, healthy lifestyle and risk of sudden cardiac death among women", "Associations of unhealthy lifestyle factors with sexual inactivity and sexual dysfunctions in Denmark", "Exercise training increases size of hippocampus and improves memory", "Activity energy expenditure and incident cognitive impairment in older adults","Exercise and pharmacotherapy in patients with major depression: One-year follow-up of the SMILE study", "The reciprocal relationship between physical activity and depression in older European adults: A prospective cross-lagged panel design using share data" and "Changes in diet and lifestyle and long-term weight gain in women and men."
In an associated development, I'm pleased to see that in July the new UK-wide physical activity guidelines have moved to the more flexible advice to get at least 150 minutes of exercise weekly rather than the older, easy-to-remember, but rather inflexible get 30 minutes per day. The press release - "UK-wide advice on activity and fitness levels" - highlights the recommendation that adults over 18 (including people over 65) should aim for at least "150mins - two and half hours - each week of moderate to vigorous intensity physical activity (and adults should aim to do some physical activity every day). Muscle strengthening activity should also be included twice a week." This brings the advice in line with the excellent US guideline that I wrote about last year. Note too the often under-appreciated importance of muscle strengthening - see the post "The recommendation to do strengthening exercises". There are a series of helpful fact sheets on the new "UK physical activity guidelines" webpage. These include "Fact sheet 1: Early years (under 5s)", "Fact sheet 2: Early years (under 5s capable of walking)", "Fact sheet 3: Children and young people (5-18 years)", "Fact sheet 4: Adults (19-64 years)" and "Fact sheet 5: Older Adults (65+ years)".
So for happier mood, less disease risk, a better sex life, improved cognitive function, and a longer life - let's get exercising!