Answer:
It is harder to deep clean a hoarder's house than it is to do daily upkeep like picking up clutter and throwing away trash...but with the human body.
While humans are young their bodies require them to move/play in order for healthy brain development, but in the latter stages of their lives hold no such enthusiasm for the daily exercise, so humans must make it a habit to keep their bodies in some sort of "shape" in their younger years so that when they to their older years their bodies will still be youthful and healthy.