Whether you rest 1 minute or 2 minutes between sets, or train at real high altitude or with a mask, you can still lift the same total amount of weight without losing strength.

Whether you lift heavy weights for fewer reps or light weights for more reps—as long as you push until you can’t do another rep—your muscles grow about the same amount.

You can make your workout feel harder and your muscles burn more by resting less between sets—but you can still lift the same total weight without getting weaker.

If young men lift light weights with very short breaks between sets for 8 weeks, their upper arms grow more than if they lift heavy weights with long breaks—even if they do the same total amount of lifting—because the short breaks create more muscle-burning stress that helps muscles grow bigger.

If you lift light or heavy weights but do the same total amount of work, your muscles grow about the same amount—whether you're using light dumbbells or heavy barbells.

If you lift the same total weight, your quads grow just as much whether you rest 20 seconds or 2 minutes between sets—so you don’t need to feel the burn to build muscle.