If you see a guy in the gym cranking out half-reps on moves like curls and chest presses, your first instinct might be to chuckle at the noob, fist bump your gym bro, and get back to your set of full-range reps.
Hold up a sec, broham.
While we normally advocate using a full range of motion for presses, curls, deadlifts, and anything else you do to promote proper joint movement and full strength development, there are some perks to half-reps: They can overload your muscles with heavier weight, strengthen weak areas of your lifts, and accumulate more volume than you would with full ROM reps.
It’s also a technique that professional bodybuilders, like eight-time Mr. Olympia winner Phil Heath, employ to increase the size and density of their muscles. Why? Simple—they work.
According to research published in the Journal of Strength and Conditioning, subjects who performed partial range-of-motion reps for 10 weeks increased the thickness of their arms as much as the full ROM group did in the same time frame. (Side note: When it comes to increasing your strength, however, the study concluded that you should stick with a full ROM.)
Here are different ways to implement half-reps into your routine based on the goal:
For strength
While a routine that solely comprises half-reps won’t do jack for your one-rep max (1RM), it can help you push past plateaus. For compound movements, like the back squat, deadlift, and bench press, a lifter usually has trouble with three areas: the bottom portion, the middle portion, and the lockout phase. Take the deadlift as an example. If you have trouble getting the bar off the ground, load a barbell with about 150% of your 1RM and pull as hard as you can (the weight isn’t supposed to move). This will train your body to get used to the stressors of moving heavy weight. However, if your issue is the middle of the lift, then lighten the load and practice pause reps, holding the weight right below your knees for a count of two to three Mississippi before completing the reps. Finally, if you can’t seem to lock out the weight, try rack pulls. Set the pins in a power rack to your shin level, but this time, place the bar on top of them. Use more weight than you normally would and pull from your shin to lockout.
For size
You can also do half-reps during some isolation exercises, preferably ones with a long ROM like preacher curls, as opposed to shrugs, which have a short ROM. You also need to be aware of when the muscle is most engaged—some muscles are more engaged during the top portion, while others are activated better at the bottom half when the muscle stretches. For example, the biceps are most engaged during the lower half of preacher curls. Therefore, doing only the top half would be less efficient.
Halves and wholes
You can also perform reps of varying ROM within one set. The best-known example are 21s, which consist of seven reps from the bot- tom to halfway, seven reps from halfway to the top, and seven full reps. Numerology aside, there’s nothing magical about either 21 or seven. You can accomplish the same with subsets of six or eight or similar amounts. Also, 21s are not exclusive to biceps routines. They work with other long range-of-motion isolation exercises, like triceps pushdowns, leg extensions, leg curls, and pec-deck flyes—don’t do them for heavy compound exercises. Or instead of doing both halves plus full reps, you can do half-reps followed by whole reps or alternate half-reps with whole reps. For example, do leg extensions for eight top-half reps in succession, followed by six full reps. You can also alternate slow half- reps with fast full reps throughout a set. Ideally, the halves and wholes will complement each other, allow- ing you to keep the muscles under tension longer than you could with only straight reps.
We’ve designed an arm routine of only half-reps to illustrate what can be done. Only one exercise per body part should feature half-reps. For safety and to ensure you hit the precise depth, use a power rack when doing half-reps of chest presses or deadlifts.
To better target half-reps of compound exercises, do them after the isolation exercises for that muscle.
Perform your half-reps slowly.
Half-rep basics
Select compound exercises that allow you to focus on specific muscles over a limited ROM, such as triceps during the lockout phase of the bench press. Select isolation exercises that have a long ROM, such as biceps curls or triceps extensions.
Combining half-reps with full reps in the same set allows you to better target muscles and increase your time under tension. And remember: 21s can be done with many more exercises than curls, like leg extensions and pec-deck flyes. Also: They don’t have to total 21 reps.
Bench-press lockout: Load a barbell with more weight than normal and lower it until your elbows are at 90 degrees (or just above), then press back up.
Preacher curls: The biceps are more engaged during the bottom half of the curl, so when performing half-reps, focus on lifting from the bottom to halfway.
Barbell curls: This move is ideal for 21s, as they have a long range of motion. Start from the bottom and lift halfway, then go halfway to the top, and then do full reps.
Overhead extensions: You don’t have to be dogmatic about your 21s. Feel free to perform any combination of half-reps and full reps. Putting your muscle under constant tension is the goal.
