Any able-bodied person can get fitter than most people who aren't very into fitness for (damn near) free, without even that much time investment. Trainers and

Any able-bodied person can get fitter than most people who aren't very into fitness for (damn near) free, without even that much time investment. Trainers and peloton classes and such give people the option to rent someone else's willpower, though. (plus leverage sunk-cost sentiments and other tricks) It's probably part of why fitness levels go up and waistlines down as one's gaze travels up the SES ladder. Someone with money who kinda wants to get fit can pay someone else to do their giving-a-shit for them, and might get fit. Someone without money who kinda wants to get fit—won't. That's what you'd expect to see even with all else, including the distribution of willpower (however we measure that) among various social classes and income levels, being equal.