Decades before sports science caught up, lifters were using 21s to build size through partial reps, stretched positions, and relentless time under tension. The method spread quickly because it was ...

Walk into a serious gym in the 1970s, and you’d often see lifters cranking out 21s — partial and full reps combined for a brutal, muscle-frying pump. These sets weren’t a gimmick; they created tension ...

Walk into any hardcore gym in the seventies and you’d see it everywhere. Lifters crowded around a barbell, sleeves rolled tight, fighting through a set of curls that burned so intensely it became a ...