This 100 rep arm finisher will crush your triceps

Everyone loves a good arm day workout, but not every routine is cut from the same cloth. Some protocols require you to pump up your guns by lifting heavy weights.

This bodyweight finisher from Men's Health Fitness Director Ebenezer Samuel, C.S.C.S., is in the latter category. Forget 21s - you'll have pushed through 100 reps by the time you complete this burner.

You're doing 50 reps of bodyweight skullcrushers, then 50 reps of close-grip pushups. Don't dally between sets, either; this is meant to be done as quickly as possible for maximum effect.

"You're resting as needed, but the amount of time you rest is very specific," Samuel says. "Your rest period in seconds is the amount of reps you have left. So if you have 30 reps of bodyweight skullcrushers to go [and you break], you have 30 seconds to rest."

That rest (or lack thereof) is important; it totally changes the dynamic of your typically staid arm day routine. "[The rest protocol] keeps things fast-paced, so your heart rate will elevate more during this finisher than it does in a normal weight training setup," Samuel says. "It also scales to your skill level easily, so if you're just learning close-grip pushups or bodyweight skullcrushers, you'll have plenty of time to catch your breath."

Since you're only using your bodyweight, you can do this routine just about anywhere. All you need is a timer and room to spread out and sweat. For best results, Samuel suggests performing the finisher after doing some weighted moves, like EZ-bar skullcrushers and pressdowns.

Bodyweight Skullcrusher

Get on the floor in a plank position, with your elbows on the ground and your toes supporting your weight. Put your palms flat on the ground (a closed fist is okay, too).
Push your hands straight into the ground to push up off the floor, squeezing your triceps to straighten your arms.

"Maintain a strong plank position when you do these, and squeeze through your glutes and abs," Samuel advises. "If you don't, you'll find that you break at the waist on every rep, making the movement easier and missing the true training effect."

If you're struggling with these, grab some elevation and put your hands on a bench instead of the floor.

Close-grip Pushups

Get on the floor in a plank position, with your palms on the ground.
Bring your hands in closer to your chest than you would for a standard pushup.
Perform a pushup.

To activate your triceps with a close-grip pushup, hand positioning is key - but you might not need them as close as you might have been led to believe be diamond pushup adherents.

"People think you need your hands touching, but that actually isn't true," Samuel says. "Depending on your back musculature, it can actually put your shoulders at risk for injury. Instead of making a diamond with your hands, think of having your hands about an inch inside of your shoulders. Focus on keeping your elbows tight to your torso on the pushup; your arms should form an upside-down "L" on the bottom of every rep."