When people stop training, their muscles don't get weaker as fast as they shrink — strength sticks around more than size, maybe because the brain and nerves keep working well even as muscles get smaller.

If you gain more muscle and strength when working out, you might also lose more when you stop — your gains and losses seem to go hand in hand.

Whether you lift your arm weights slowly or with a little swing, your biceps and triceps both get noticeably bigger after eight weeks of training—your triceps grow even more than your biceps.

If you build muscle and get stronger by lifting heavy weights, you won’t lose those gains even if you stop training for eight weeks.

If you've never worked out before, lifting weights for 10 weeks can make your muscles stronger and bigger — especially in your legs and arms — while people who don’t train see almost no changes.

Doing bicep curls one arm at a time makes your right arm stronger than doing them with both arms together, but doesn't make your biceps bigger than using both arms.