Crew practice. Every stroke.
Swimming practice, esp on cold days outdoors in May.
many many teachers classes which were necessary, but the teachers sucked.
5 years in the submarine Navy. Ever been to sea for 56 days and not seen the light of day? Or floated for 6 months? Or started a nuclear reactor seasick AND still inebriated from the night before?
North of 50% of ALL of formal schooling.
Nuclear Engineer school.
Caddying in 100 degree heat, 2 bags, 4 hour rounds, 3 rounds in a day, for less than $40 USD.
Pretty much every jiu jitsu session. I don't even like it, but it's a good skill and need to be an example for the kiddies.
Talking with you on Twetch, telling me I don't know nuthin, while I grit my teeth to preserve your softshelled innocence.🤣

This is just a short list.