Here’s the problem with most fitness programs: they act like your resources (time, money, patience, value for potential returns, etc.) are limitless. They’re not. Here’s how I like to frame any program you’re likely to take on:
This flow never ends. Each number has a reality; let me elaborate:
- You have to do this stuff until you die. You cannot workout REALLY hard and just live on “fitness interest” for the rest of your life. Long term studies have demonstrated that college athletes who quit after school have the same health outcomes as those who do no formal exercise over their life.
- We do not adapt to infinity; we reach a limit of improvement. Once you’re on the shoulder, gains are very very slow. Really, within a year, you know who you are and what you’re capable of getting from a training program. Given 1&2, one should strive for the minimum effective dose (M.E.D.). How little exercise do you NEED to do to maximize whatever you can get? Because…
- Increasing the stimulus past X level doesn’t result in a greater response. How much improvement you can achieve is a function of your genetics. Once you’re working with ENOUGH intensity and volume (really, the smallest about you NEED), your body will give you what it can give you. More stimulus just increases wear and tear, leading to burnout, which is a shame because…
- If you’re going to keep the benefits you build, you have to do this stuff until you die.
It’s like the circle of life, except no hyenas.
Skyler Tanner 
I’m not sure I see the value or necessity of limiting oneself to the minimum effective dose throughout the course of a lifetime, just because what I do today might not be sustainable when I get older. I might live to be 100. Should I always limit myself to what I think my 100 year old self will be able to handle?
At no point did I say the MED for your last year on Earth.
I was reacting, perhaps too strongly, to point #4. If would be nice if you could retain what you’ve built as a young man all the way to the end of your life. But that doesn’t seem realistic. Rather, hang on to as much as you can, for as long as you can. Just don’t overdo to the extent that you accelerate, rather than slow down, the decline.