I am going to go exercise right now. I don't exercise much, which is bad (I know), so it's about time to do something about it. We all should. I am glad that people do studies like this. Helps us think about our fitness and health.
I know someone who as far as I know never ever exercised in last 50 or so years, and he is still going pretty strongly at 75 years of age. But anyway, I think he is an exception not the general rule. So a 15 minute exercise is a better bet anyway
I would say it is the best bet we have. What can we do about it when we are older? Nothing, only cry about how much we didn't exercise and take care of ourselves when we were younger.
And wow, they must be really lucky, or eating healthily.
Astronauts aboard the ISS craft miles of technically superior optical fiber