Back in the day, even before Arnold was the Terminator and Lou Ferrigno was the original Hulk, gyms looked very different from what you see today. The bodybuilders of the 70s are very much the grandparents of today's CrossFit workout.
"Low-tech weight lifting has been a main-stay in fitness," Olson says. "It was originally used by bodybuilders and power lifters, lifting heavy iron in basements, warehouses, or garages—which goes to show that truly amazing feats of fitness are not about bells and whistles," Olson says.
Today's most popular "no frills workout," CrossFit, has participants complete a WOD [Workout of the Day] which often includes doing as many reps as possible (AMRAP) of moves like squats, pull-ups, and box jumps in a very bare-bones gym setting (many don't even offer incidentals like air conditioning).
Why is it still a hit? "While this workout may not be for everybody in every age group, lifting iron of any kind, from dumbbells to bars to iron chains, will produce strength and muscularity," Olson says.