A hundred billion dollars is a boatload of money. You'd think earning it would be hard, and indeed for an individual it is. But for society in general, it turns out, it's weirdly easy to become that much richer. All we have to do is get off our butts and walk or jog an extra 15 minutes a day. 

That's the conclusion of new research conducted by health insurance group Vitality and the think tank RAND Europe that looked at data on 120,000 people in seven countries. 

A hefty price tag for our collective laziness

It's no shock that way too many of us are out of shape and that this flabbiness has serious health and economic consequences. You can see that just by looking around or reading about skyrocketing healthcare costs. But while it's easy to spot the immediate human toll of our lack of fitness, it's harder to wrap your mind around what it all means in the collective. 

RAND set about to fix that by running several simulations of what would happen if we all shaped up and started exercising more. While the various levels of activity increase and how each plays out economically get a bit complicated, the bottom line is crystal clear. A little bit more exercise would save us a hefty amount of money. 

The report "found that if all adults aged between 18 and 64 walked 15 more minutes a day, it could increase world economic output by some $100 billion year on year," sums up EuroNews.

Bigger increases in activity would lead to larger projected gains. If everyone got the WHO recommended minimum of 150 minutes of moderate exercise a week, global GDP would rise by more than $300 billion a year. 

Those increases are down to fewer absences, longer working lives, and less "presenteeism" where people show up but don't accomplish much because of ill health, the report explains. 

Even a little exercise does more good than you think.  

While the headline numbers might sound eye-popping, it's not surprising that modest increases in activity levels can have a significant impact on our health. Study after study has found that quite small amounts of exercise have real benefits. 

One recent study from the American Cancer Society that looked at 140,000 people showed just 15 minutes of walking a day reduced older Americans risk of disease and lead to a longer life. Even just ten minutes of walking has been shown to have cognitive benefits

All those little improvements can actually add up to a healthier - and richer - world. Lacing up your walking shoes won't turn you into Jeff Bezos, obviously. At a global scale, $100 billion a year isn't even that much. But this study is a helpful reminder that small health choices add up. Don't be discouraged if you're never going to be a CrossFit regular. Less heroic amounts of exercise will make a dent in your health.

The report is also a reminder to bosses that nudging their people towards wellness has real, financial benefits. Subsidizing gym memberships, championing walking meetings, or offering the flexibility your staff need to make that spin class or go surfing isn't just nice. It will make you - and the rest of us - a little bit richer.