People who’ve never lifted weights before gain muscle much faster than those who’ve trained before—even if they do the same workout.

If you've never lifted weights before, your muscles grow bigger faster from training than someone who's been lifting for a while—even if you both lift the same amount of weight, because your muscles are more responsive when they're new to exercise.

People grow muscle at very different rates — but each person tends to grow their arms and legs similarly, no matter what weight they use. This means your genes and biology matter more than how heavy your weights are.

If you’ve been lifting for a while, doing more workouts over time will help you build more muscle than just lifting heavier weights.

Doing your workouts more often per week doesn’t seem to help you build more muscle, as long as the total amount of lifting stays the same.

If you lift weights until you can't do another rep, you might build more muscle than if you stop before reaching that point—but we’re not totally sure yet.