I was one who discovered the delights of cross-country running and working out in the gym after I left school. I was a weedy kid who loathed these activities at school. Later, I found I could easily outrun any beefcake or built lad and do three or four times as many chin-ups, etc. My power was low but my weight even more so, so my power-to-weight ratio was high.
The introduction to PE at school was poorly done and it did not cater for those who were not yet fit and who had not yet discovered the satisfaction of a fit and exercised body.
I now struggle to tolerate and understand those not into physical activity, etc, and might easily become a PE master who slippers the slow, the slothful and the physically inept and who favors nude swimming, shirtless games, and compulsory showers – if I let myself.