Just 15 minutes of exercise per day prolongs life

By Dr. Ananya Mandal, MDAug 17 2011

Taiwanese researchers reported Monday in the journal The Lancet that exercising for just 15 minutes most days of the week appears to provide health benefits by prolonging life.

The regular recommendation is 150 minutes of exercise a week. Dr. Chi-Pang Wen of the National Health Research Institutes and China Medical University Hospital and Jackson Pui Man Wai of the National Taiwan Sport University sought to learn if less activity than that would also make a difference.

The team looked at health records of 416,175 healthy men and women over 12 years who had received routine health screenings and had ranked their level of exercise as inactive or low, medium, high or very high activity, the team found that leisure time physical activity of only 15 minutes was associated with a 14% reduction overall in death, a 10% reduction in cancer mortality and a 20% reduction in cardiovascular disease, compared with that of inactive people.  Life expectancy went up three years.

The study added that a third of Americans get 150 minutes of exercise per week; East Asians are more sedentary.  Knowing that even short workouts could improve health might help physicians get more people exercising, the authors noted.

Dr. Anil Nigam of the Montreal Heart Institute and Dr. Martin Juneau of the University of Montreal in an accompanying commentary wrote, “This advice is very simple and probably easily achievable…The knowledge that as little as 15 minutes per day of exercise on most days of the week can substantially reduce an individual's risk of dying could encourage many more individuals to incorporate a small amount of physical activity into their busy lives.”

“The 30-minute a day for five or more days a week has been the golden rule for the last 15 years, but now we found even half that amount could be very beneficial,” said Dr Chi-Pang Wen, lead author of the study. “As we all feel, finding a slot of 15 minutes is much easier than finding a 30-minutes slot in most days of the week.”

“To get started by the inactive is the most difficult challenge or make the couch potato move the first step,” Wen said. “We hope this 15-minute message can facilitate the inactive into moving ... the inactive constituted the majority worldwide.”

“Do inactive people live shorter lives, and get more cancer, because of their inactivity?” said Dr. Daniel Blumenthal, chair of the department of community health and preventive medicine at Morehouse School of Medicine in Atlanta. “Or are they inactive because they are ill [perhaps they are getting cancer] and it is this illness that leads to their earlier death? Does inactivity lead to illness, or does illness lead to inactivity?”

While the answers to these questions remain a cause of debate, Dr. Paul Thompson, director of the Athlete's Heart Program at Hartford Hospital in Connecticut, made a few suggestions on how to work those 15 minutes of fitness in a day. “Climb stairs, park in the far corner of the lot, towel off vigorously; there are a myriad number of ways we can engineer exercise into our lives,” Thompson said. “I get a kick out of the folks who join the gym and then take the elevator up two flights or hire someone to do the lawn.”