You’ve probably already done several squats today: Every time you sit down and stand up, you’re performing a squat. That’s why it’s one of the most functional moves you can have on your training plan.

One evening in the early 1970s, Michael Pachovas and a few friends wheeled themselves to a curb in Berkeley, Calif., poured cement into the form of a crude ramp, and rolled off into the night. 1 For ...