This month’s cover star, Vin Diesel, may not be a kid anymore (he turns 50 this year), but he’s still got arms the size of armored tank cannons—to shame guys half his age. Hell, to shame guys of any age. So how does he keep them perpetually loaded for battle? He attacks the biceps and triceps from all sides and often holds moves for teeth-grittingly long periods of time to really tease out the size and feel the burn. And pray that when you put a few years on, you’ll still be packing even a fraction of the heat he is. 

How it works:

The longer muscles spend working while tensed, the better they adapt to the load by getting bigger and stronger. This routine trains the bi’s and tri’s from every angle and keeps them under tension for extended periods. Some sets will last as long as a minute—prepare to feel the burn.

Directions:

Perform the workout once per week. On exercises that call for 60-second sets, choose a load that allows you about 30 reps, but don’t go for a specific number. Set a timer for 60 seconds and perform as many reps as you can with perfect form and a normal cadence. Don’t rush.

Note: You can turn this into a total-body beast by adding a few sets of barbell squats, deadlifts, and bench presses.