[kelnos]

That's a perfectly valid comparison. A year's worth of hours is still a year's worth of hours, regardless of what time span I spread it over.

We use this sort of formulation everywhere. If I say I work 40 hours a week, no one is going to assume that I start work at 9am on Monday, work non-stop until 1am Wednesday, and then take the rest of the week off. If I say that people spend approximately a third of their lives sleeping, no one thinks I mean that they sleep continuously from birth until they're 30 years old, and then spend the next 60 years awake.

[unop]

Umm, the front-loaded 8k hours might not have much return if you were sedantary in the later decades (arguably the years where exercise helps stave off metabolic disease) as much as sustained levels of exercise all through life.

I mean, we all know of the university budding sports star types who probably invested in many hours training and trying to break into their sport professionally but not quite cutting it - and then "retiring into mediocrity" with the regular 9-5,2 hour commute, 3 kids and the diet to match. They exercise no differently to the regular Joe and suffer all the maladies the same.

[sersi]

The point is that it's 8500 hours of free time used for exercise. It's time when you're not eating sleeping or working.

So it's not exactly the same. For people who have very little free time due to commute, work, children, etc. It's harder to spend half an hour of free time a day on exerciaing.

I mean I do agree with the premise that exercising is a good return (especially since the better sleep quality should be factored in) but I think the person you're replying to has a point when he says that saying it's one year of life is not really comparable