Since the Twilight film series has erupted, everyone knows Taylor Lautner—otherwise known as Jacob the werewolf. But did you know that Taylor actually had to work really hard bulking up for his role in the second Twilight film? Did you know he actually had to gain 30 pounds of muscle in just one short year? He shared the secrets of his muscle-building workout tips with Men’s Health.

When it comes to working out in order to build muscle and bulk up, Taylor pushed his limits and tried to (safely) lift as much weight as he could. The secret was to push his limits in a safe way. If you’re interested in adding bulk, the formula is to add about 40% more weight than you could normally lift ten times. Then, you should use a spotter and perform only the eccentric part of your reps unassisted (the lowering half of weight lifts.)

However, in order to have a balanced body, you’ll need to vary your repetitions and the weight that you are lifting. In fact, the article informs us that “a recent study in the Journal of Strength and Conditioning Research found that men who regularly varied their rep counts and trained different muscle groups increased their bench strength by 28% and their leg-press strength by 43%.” Impressive!

But how do you feed your newly-bulked-up body? The article provides readers with a formula to calculate your daily calorie goal:  Goal weight x (workout hours per week + 9.5) = daily number of calories. What’s yours?

As if all of Taylor’s innermost secrets and workout tips weren’t enough, we’re also given a step-by-step guide of how to work out exactly like the movie star works out. Did you know that Taylor uses a medicine ball to work out? Neither did I…and now I’m thinking maybe it’s time to put my old medicine ball to work!