Impact of differing eccentric-concentric phase durations on muscle damage and anabolic hormones

To figure out whether speeding up or slowing down the lifting vs. lowering part of a weight workout makes your muscles grow more, scientists need to test each part separately—not at the same time.

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.

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.

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.

After doing weightlifting with different speeds for lowering and lifting the weights, your body’s LDH levels don’t go up or down in a meaningful way — they just stay about the same.

When you lower weights slowly during strength training, your body might release more growth-friendly hormones and cause more tiny muscle tears—this could help your muscles grow bigger over time.