Epigenetics; Epi means on top of. Genetics are what you’re born with. The optimistic thought is this: while you cannot change the base level of your genetics, you can still modify your genetics through training, the environment, and exercise.
I often joke and I say that I don’t believe in genetics, when it comes to the gym and weightlifting. This is what has helped me deadlift over 500 pounds, and squat over 400 pounds; this disbelief in genetics. And the pure belief in personal desire, time and effort.