For guys who lift weights, doing the lowering part of a lift slowly (2 seconds) and the lifting part quickly (1 second) might boost certain hormones more than other lifting speeds.

If you slow down the lowering part of weightlifting, your muscles might get more damaged and your body might release more of the hormones that help build muscle—this is what the claim says about guys who lift weights.

When men who lift weights do a slow downward motion (4 seconds) on exercises like squats or bench presses, their muscles seem to get more damaged afterward than when they do faster or slower movements — and this shows up as higher levels of a certain protein in their blood.

When young men lift weights regularly for 15 weeks, their body’s immediate hormone spike after each workout stays about the same—no matter how many times they do it. It’s like their body keeps reacting the same way every time, without getting used to it.

When young men lift weights for 12 weeks, their short-term spikes in testosterone and IGF-1 after workouts don’t seem to predict whether they’ll gain more muscle or get stronger.