Tyson's REAL routine in 1987

[Squirrel]

ya'll listen to this guy, genetics plays a mayor role. You can improve and add muscle mass but been a skinny mofo and achieving a physique like Tyson is a very very uncommon thing. Same way, some ppl are born faster and more explosive than others, again, genetics.

It's uncommon cause it takes a LOT of dedication and drive, as well as a stringent diet and lifting program.

Genetics do indeed dictate the rate at which you can gain mass, but not the the extent that some individuals can lift for 5 years and see no improvement. Some people gain mass easily and see results quickly, others have to be more dedicated and precise to see those same gains.