Emotional strength, you won't build this at the gym.
Where does the ability to remain true to ourselves and our goals come from?
Are you born with it? Do you develop it because of childhood experiences or perhaps in spite of them. Is it part of your DNA
Accepting responsibility for yourself takes strength and courage.
It's much easier to blame others and in fact our brains are wired to seek out that 'blame buddy' if we can because making ourselves responsible can be hurtful.
Maybe true emotional strength is the ability to take responsibility without blame?