Author + information
- Duck-chul Lee, PhD∗ (, )
- Russell R. Pate, PhD,
- Carl J. Lavie, MD,
- Xuemei Sui, MD, PhD,
- Timothy S. Church, MD, PhD and
- Steven N. Blair, PED
- ↵∗Department of Kinesiology, College of Human Sciences, Iowa State University, 251 Forker Building, Ames, Iowa 50011
We would like to thank Dr. Murakami and colleagues for their interest in our paper (1). Exercise is Medicine is a global health initiative by the American College of Sports Medicine to promote and include physical activity (PA) as a prevention and treatment option of diseases in all medical care. Knowing the minimal effective dose of exercise, as a medicine, is important from both clinical and public health perspectives. The current aerobic PA guidelines from the World Health Organization recommend at least 150 min/week of moderate-intensity or 75 min/week of vigorous-intensity PA, or an equivalent combination of both (2). Although some PA is better than none, it still remains uncertain whether 150 or 75 min/week of moderate- or vigorous-intensity aerobic exercise is the precise and effective minimal dose of exercise for health.
In our recent study, a minimum of 30 to 59 min/week (5 to 10 min/day) of vigorous-intensity running showed 28% and 58% significantly lower risks of all-cause and cardiovascular mortality, respectively, compared with the risks associated with no running (1). On the basis of evidence from the Japanese National Institute of Health and Nutrition, the Japanese government recommends goals of 60 min/day of moderate-to-vigorous PA for adults (18 to 64 years of age) and 40 min/day of moderate-to-vigorous PA for older adults (≥65 years of age). However, the most important main message is “+10 min/day of moderate-to-vigorous PA” as a minimal starting dose of PA for everyone to encourage both sedentary and active individuals to become progressively more active (3). This is currently the lowest specific dose of PA for health promotion recommended and published by a government agency.
Current PA guidelines are developed largely on the basis of observational studies using self-reported exercise, which are prone to underestimate the true health benefits of exercise because of over-reporting. Therefore, the current minimal dose of exercise could actually be lower than 150 or 75 min/week if it was accurately reported or objectively measured. In fact, we found that measured cardiorespiratory fitness, an objective marker of habitual PA, predicted mortality better than self-reported PA did (4). Furthermore, 62% of Americans meet the aerobic PA guidelines based on self-report, however, only 10% meet the guidelines based on objective accelerometry (5). It is conceivable that future PA guidelines based on objective measures could possibly recommend a lower minimal dose of PA, one that is below the current guidelines.
Considering recent studies suggesting the health benefits of low doses of PA, the Japanese PA guidelines promoting, “Let’s start with +10 min/day of activity,” is a proper and more attainable public health message, as described by Murakami et al., which encourages and motivates more people to start increasing PA. Exercise is the best medicine with the least side effects to prevent and treat most chronic diseases for overall physical, mental, and social well-being.
- American College of Cardiology Foundation
- Lee D.C.,
- Pate R.R.,
- Lavie C.J.,
- Sui X.,
- Church T.S.,
- Blair S.N.
- ↵World Health Organization. Global Recommendations on Physical Activity for Health. 2010. Available at: http://www.who.int/dietphysicalactivity/factsheet_recommendations/en/index.html. Accessed October 20, 2014.
- ↵Ministry of Health, Labour, and Welfare. ActiveGuide: Japanese Official Physical Activity Guidelines for Health Promotion. Brochure in English. March 2013. Available at: http://www0.nih.go.jp/eiken/info/pdf/active2013-e.pdf. Accessed October 20, 2014.
- Lee D.C.,
- Sui X.,
- Ortega F.B.,
- et al.