"Of particular concern to couch potatoes, gamers, and anyone who spends an inordinate amount of time sitting and staring at a screen is how little exercise can I do and still receive a benefit. A new study entitled 'Minimum amount of physical activity for reduced mortality and extended life expectancy: a prospective cohort study,' answers this important question. The conclusion: 92 minutes of moderate activity a week can extend your life by three years."
On of the commenters notes:
"It gets better--following their math, 92 minutes a week gives a 14% reduction in mortality from all causes, and every additional 15 minutes gives an additional 4%. there's no point of diminishing returns identified. So, if you exercise 7 hours a week, you become immortal."