Lifting weights slowly or quickly between half a second and 8 seconds per rep doesn’t seem to make a difference in how much your muscles grow — as long as you’re doing resistance training.

Whether you lift weights slowly or quickly, as long as everything else stays the same, you’ll likely build about the same amount of muscle—so how fast you move the weight might not matter much.

Whether you lift weights slowly or quickly, you’ll likely gain about the same amount of muscle—so don’t stress over the speed, just keep lifting.

Whether you lift weights slowly or quickly, you’re likely to gain about the same amount of muscle — the speed doesn’t seem to make a big difference.

If you lift weights until you're really tired, it doesn't matter if you lift slowly or quickly—you'll still build about the same amount of muscle.

Lifting weights fast or slow doesn’t make much difference in how much your muscles grow — the extra gain from going slow is practically nothing.