To build arm size, strength and muscle, you need to lift heavy and you need to lift hard. But there’s another, often underrated, piece of the arm-building equation: time under tension. Your biceps and triceps need to squeeze – and keep squeezing – throughout each rep and set, pushing blood into the muscle and building a strong mind-muscle connection.

That’s exactly what you’ll do during the count-up, count-down triceps blast finisher from Men’s Health US fitness director Ebenezer Samuel, C.S.C.S. This brutal series has you completing 20 reps of triceps work from two different angles – but you’re not just racking up reps. ‘You’re also accumulating a ton of time under tension for the “non-working” side,’ says Samuel. ‘Basically, save for the split second when your muscle relaxes after the more classic reps, your tris are never not working.’

That adds up to about a minute of constant work for your triceps – and you’ll feel it in a vicious pump after every set. You’ll need a looped resistance band to perform the count-up, count-down triceps blast.

The Triceps Finisher

  • Start in a tall kneeling position, glutes and abs tight, ribcage down, shoulder blades back. Grasp a looped resistance band with straight arms, essentially in the bottom of a triceps pressdown position. Squeeze your triceps.
  • Keep your right arm in a tight, straight-arm position, making sure you’re squeezing your triceps to maintain that position. With your left arm, bend at the elbow and return to the top of a pressdown position, then contract your triceps and press back down. Squeeze your triceps to maintain the straight-arm position with your left arm, then perform a single rep on the right arm.
  • Repeat the pattern, this time maintaining the straight-arm position on the right arm while you do two reps on the left. Continue this pattern two more times, adding a rep each time (so the final round has you holding a straight-arm position with one arm while doing four straight reps with the other).
  • Hinge forward, keeping your abs tight, and drive your arms out in front of you. Your upper arms should be at roughly a 90-degree angle to your torso. Keep your abs tight to hold your ribcage down. Look at the floor to keep your neck neutral.
  • Maintain the straight-arm position from this angle with your left arm while you perform four skullcrusher reps with your right. Then switch, holding a straight-arm position with your right arm while you rep with your left.
  • Repeat the pattern, this time doing three reps with each arm, then two, then one.
  • Complete three sets.

You’ll rack up serious time under tension – and your triceps will be screaming. But there’s more to this series than that, says Samuel. ‘You need to focus on keeping your hips and shoulders square when you do this,’ he says, ‘and that’s going to tax your core more than you think.’ Your abs and glutes will benefit from the move, even if they’re not completely torched. ‘Not every core exercise is going to leave your abs on fire,’ says Samuel. ‘But trust me: they’ll be putting in work on this one.’

You can use the count-up, count-down triceps blast in a variety of ways. It works as a finisher to a triceps workout, an accessory move on a bench-press day, or an arm-day finisher. ‘Or, if you’re in a time crunch,’ says Samuel, ‘this is a great way to get a quick triceps pump as a standalone workout.’