Of course there are other factors that need to be present, but without the foundation of healthy, fit body, no progression is ever really possible, and absolutely never in the long term. Of course there will be individuals that are exceptions to the rule, the super athletes whose body's can take a tremendous pounding - now.
We have generations of ex professional athletes, construction workers, military personnel, firefighters, with many heath issues, from hip replacements, to wheel chair bound, to dementia to lung disease. These men and women put their health on the line for their profession, I did the same thing as a firefighter in the ghettos of Brooklyn for 20 years.. They knew what they were doing, the effect it might have, but did it anyway.
Average Joe does not need to slam his body to the floor hundreds of times, until his feet hands and feet bleed. There are much better, highly efficient ways to positively effect the muscular and cardiovascular systems. This is the 21st century, take advantage of the knowledge available out there, but don't get lost in the hype while you're searching for what works for you.