The rate of return on exercise

These are illustrative numbers, not definitive estimates:

Let’s make some base-case assumptions. The most important assumptions are:

1. A 50 year old male who doesn’t exercise can expect to live to age 80
2. That same male who puts in 8 hours per week of exercise can expect to live to age 88.
3. We will measure investment and return in terms of hours per year
4. We assume people value their waking hours, and sleep 8 hours a night. We don’t count the 8 hours of sleep as “return” though you of course could decide to do so.
5. The exercise continues every year, even after age 80
6. The exercise costs only the time allocated to it and provides only the expected extra years of life (i.e. no “disutility” or “utility” except the expected life extension benefit[14] )
7. Everything else is constant

Given these assumptions, we can compute a “rate of return” just as we would with dollars.

When we do so we find that the return on investment is 5.8%.

Here is more from Roger Silk, including a table of sensitivity parameters, from his blog on investing.