By Jimmy Peña, MS, CSCS
Nothing beats a controversial statement, so let me throw one at you: The skullcrusher is the single-best triceps exercise you can perform. A number of you may agree with that statement, and some of you may not. But that’s really not the point I’m going to make here. Rather, nobody will contend with the assertion that repeatedly performing the same exercise from one workout to the next will have diminishing results. If your arms have stagnated and you consider the skullcrusher one of your go-to moves, it’s time to once again make the skull a novel exercise that can stimulate new gains. Easier said than done? Absolutely not! We’re going to show you four completely different ways to do the skullcrusher to make it an altogether different exercise, all of which will do your triceps a favor.
It’s important to remember that the triceps have three muscles: the lateral, medial and long heads. While you can’t target each without stimulating the others to some degree, you can involve one over another based on the angle of your arm relative to your body. The skullcrusher (upper arms perpendicular to your body) puts the lateral head as well as the long head under some severe tension, which is why most bodybuilders stand by it. But while the skull is king, the focus here is on ways to manipulate it and make it work for you while still targeting the muscles that are most prominent to the size and shape of your upper arms.
Assembled herein are four skullcrusher exercise variations that all have the essential elements of the skull but with striking differences that’ll dramatically stress and target your musculature and form.
1. Single-Arm Dumbbell Skull
While some benefits of single-limb moves are obvious, others might surprise you. For starters, with most exercises you can produce more force on each side of the body than you can using both sides together. Simply stated, when you use both arms simultaneously, the equal weight on both sides of your body balances your torso. When you examine the single-arm skullcrusher, the torque or body english is less than say the dumbbell row, but it’s still present. The single-arm skull also puts your core musculature on overdrive, which helps establish a better base of strength and stability for virtually every other move or technique you choose to tackle.
A more obvious advantage of performing the skull using one arm at a time is your ability to apply intensity techniques such as forced reps. Being able to self-spot can be a critical factor in inducing change to your upper arms. By simply applying enough assistance to move the working arm through the range of motion, you can push past failure on each arm. By doing each side independently, you can also identify weaknesses on either side of your body. Perhaps your left triceps is weaker than your right side, and by training each side individually you can target that weakness and get it to catch up with the other side. That imbalance could be the reason other moves and bodyparts, such as your chest, shoulders and relative presses are lagging behind as well.
One important factor to remember is that every time you incorporate single-arm moves into your routine, start your session or sets using the opposite arm with which you began your last session. That way, each side gets to be worked when your muscles are freshest.
2. Partial Skull
As you know, we’re big fans of the partial reps technique simply because it allows you to monumentally overload a muscle to spark growth. For those who’ve never attempted partial reps or find them odd because of the shortened range of motion, the triceps are a good place to incorporate them. For one, partials are about breaking the full range of motion into smaller components and blitzing the target muscle within those isolated ranges. Best performed inside a power rack, partials can mean a few inches at the top of the move or halfway down — or anywhere in between. The great thing about using a power rack for the partial technique is that you can adjust the safeties to different levels without worrying about the bar crashing down on you, nor do you need a spotter to assist you, so they’re great if you train alone. In fact, because you’re working in a shortened distance, you can actually move more weight than normal within each level as compared to the amount of weight you could lift through a standard full range of motion.
However, the partial reps technique is angle specific, meaning you have to train in as many different angles as possible to get the full-range effect. What happens is that once you’ve blasted your triceps at various angles throughout the skullcrusher’s path of the bar, your triceps will have gained strength at each angle, making you better able to handle a full-range skullcrusher with a heavier weight. The stronger you are at each smaller component or distance, the stronger you’ll become overall and the bigger your arms will become.
3. Cable Skull
If you’ve been in the gym for more than a week, you’ve quickly learned that cables offer something that not even free weights can provide: constant tension. And in no other exercise is that more critical than during skullcrushers. You see, typically at the top of a skullcrusher when your arms are outstretched above you and pointing to the ceiling, it’s important to squeeze and tighten your arms to create tension because otherwise the triceps have the ability to relax to a certain degree. At that angle, gravity is pulling the weight downward into your hands, which are supported by your straight arms. If you’re not careful, that top position can easily become a resting point for your upper arms.
Enter the cables. With the cable version of the skull, you can forget about any moment to rest because the cable, by pulling from the angle of the cable to the bar or rope attachment, you’re always at work. One important tip is that you may need to adjust the bench up or away from the low pulley so that the plates don’t bottom out; if they do, you’ll lose the element of tension the cables are so good at providing. Add to that the fact that incorporating intensity techniques such as drop sets and rest-pause are so much easier to use with cables than other forms or versions. A quick switch of the pin and you’re ready to go, as opposed to having to strip weight off the bar. For a different feel, you can adjust the bench to an incline, which will force your arms back and above your head even more, targeting the long head to an even greater degree — much like an overhead extension. We’re so confident in this cable version of the skull, we trust it could become one of your favorite arm exercises.
4. 45-Degree Skull
We saved the 45-degree skull for last because it best incorporates many of the elements the other moves provide. For one, the angle of your arms allows for a semblance of that constant tension that the cable skull provides at the top of each rep. By not allowing your arms to be perpendicular to the body, your triceps are at work throughout each rep and at every stage through the range of motion. You also target and stimulate the long head of the triceps with better success since your arms are more overhead than at your sides. The path of the bar is also altered as you bring the barbell toward the end of the bench or the top of your head as opposed to the middle of your forehead like the standard skullcrusher.
If you don’t have a spotter, you may want to shift your body down the bench slightly so that there’s space on the bench for you to rest the bar between sets and also allows you to lightly tap the bar against the bench as a small means of support or bounce to aid you in each rep as you approach failure.