Doing just 15 minutes of moderate exercise a day may add three years to your life, a large study in Taiwan has found.
Most people struggle to stick to the standard guideline of 30 minutes a day of exercise, five days a week, and experts hope that by identifying a lower dose, more people will be motivated to get off the couch.
Lead researcher Chi Pang Wen of Taiwan's National Health Research Institutes said dedicating 15 minutes a day to a moderate form of exercise, like brisk walking, would benefit anyone.
"It's for men, women, the young and old, smokers, healthy and unhealthy people. Doctors, when they see any type of patient, this is a one-size-fits-all type of advice," Wen told Reuters in a telephone interview.
Wen and colleagues, who published their findings in medical journal The Lancet on Tuesday, tracked over 416,000 participants for 13 years, analysing their health records and reported levels of physical activity each year.
After taking into account differences in age, weight, sex and a range of health-related indicators, they found that just 15 minutes of moderate exercise a day increased life expectancy by three years compared to those who remained inactive.
"The first 15 minutes ... the benefits are enormous," Wen said.
Daily exercise was also linked to a lower incidence of cancer, and appeared to reduce cancer-related deaths in one person in ten.
"Sooner or later, you are going to die. But compared to the inactive group, the low exercise group has a reduction of 10 percent in cancer mortality," Wen said.
Wen said the Taiwan findings were consistent with similar studies in the past using Caucasian participants, but his team was the first to come up with the minimum level of exercise necessary.
"None of the other papers were able to conclude ... what specific amount of exercise would be enough. Ours is the first one to say that 15 minutes would be enough," he said.
"We hope this will make it more attractive for inactive people, that they can allocate 15 minutes a day, rather than 30, which is more difficult."