MariposasLifting Tempo
Lifting tempo refers to the speed at which you move through each phase of a repetition: how fast you lower the weight, whether you pause at the bottom or top, and how quickly you drive back up. It's usually written as a four-digit code, like 3-1-2-0, where each number represents seconds spent in a specific phase (eccentric, pause at bottom, concentric, pause at top, in that order). Slowing the eccentric, or lowering, phase builds more time under tension in the muscle, which is one of the key drivers of hypertrophy independent of the load on the bar. The nuance most people miss is that tempo changes the effective difficulty of a set dramatically without changing the weight at all. A set of ten reps with a three-second lowering phase is a completely different training stimulus than ten fast, bouncy reps, even if the dumbbell is identical. Tempo also forces honest range of motion because you simply cannot cheat a slow rep the same way you can rush through one.
Example
Say you're doing a barbell back squat with a 4-0-1-0 tempo: you take four full seconds to descend, skip any pause at the bottom, then stand up in one second with no hold at the top. That four-second lowering phase puts the quads and glutes under sustained tension through the hardest range of the lift, making a moderate weight feel significantly harder than your usual go-to load. Many coaches program this style of squat in the eight to twelve rep range specifically to build muscle without piling more plates on the bar.