Ab Exercise Selection Guide
Stick to stable exercises with lots of ROM, that are limited by the target muscle group and that you can load properly. For abs, this includes crunches, ab wheel roll-outs, leg raises on a roman chair and side bends. If your goal is growth, you’re best off avoiding planks, endless crunches and getting punched in the abdomen. Read on to find out why.
The Abs Specialisation Template is out now and is 33% off for the next week! No discount code required. Check it out!
N.B. Throughout this post, I’ll refer to all the major abdominal muscles collectively as the “abs”.
What do the abs do?
The abs collectively probably have four functions that are worth training to grow them; spinal flexion, hip flexion, bracing/increasing intra-abdominal pressure and lateral spinal flexion. Bracing/increasing intra-abdominal pressure is already being trained through some properly performed lower body compound exercises like squats and deadlifts. That leaves only spinal flexion, hip flexion and lateral spinal flexion to be directly trained.
Contrary to popular belief, compound exercises aren’t great at building a “six-pack” (which mostly refers to the rectus abdominis muscle being visible and large). This is because the rectus abdominis primarily works to flex the spine and hips. During squats and deadlifts, you’re mostly RESISTING spinal flexion using your lower back and actively using your glutes to extend your hips – using your rectus abdominis a lot would make you fold over!
Strictly speaking, lateral spinal flexion and hip flexion exercises may not be necessary to maximise oblique growth, since the obliques do also contribute to spinal flexion exercises. I’ll suggest some in this article, but feel free to omit them from your training and see how your core develops before including them.
Crunch on Decline Bench
Using a decline bench/sit-up bench allows you to get more spinal flexion ROM.
Ab Wheel Roll-Outs
When properly performed, ab wheel roll-outs train the abs through both hip flexion and some spinal flexion. Because the abs need to produce the most tension when they are very lengthened, this exercise can be quite effective for growing the abs.
Leg Raises on Roman Chair
Leg Raises train both the hip flexion and spinal flexion functions. The reason the roman chair is preferred to hangings leg raises is because hanging likely doesn’t contribute much, if at all, to ab growth, and has a poor SFR for the lats and forearms, which get fatigued from holding on to the bar.
Cable/Dumbbell Side Bend
Side Bends train the obliques through lateral spinal flexion. Unfortunately, dumbbell side bends only train the obliques through a partial ROM. When set up properly, you might be able to get a fuller ROM using cables. Either way, you can get a deep stretch, which is likely the most important component of the ROM anyhow.
What NOT to do
Planks
While planks get a lot of love, they’re likely not ideal for ab growth. They are an isometric exercise for the abs (you’re resisting spinal extension) and there are a lot of supporting muscles which also do not get much stimulus out of planking, such as the triceps.
50+ reps of partial crunches
Based on the available literature, we’re fairly confident that full ROM is better for muscle growth than partial ROM. We’re also somewhat confident that there is a bottom end for maximally effective intensities (%1RM) for muscle growth, which is likely around 20-30% 1RM. Above that threshold, sets are roughly equivalent as far as how much muscle growth they induce. Doing sets of 50+ reps on partial ROM crunches is almost certainly not an ideal way of growing the abs.
Getting punched in the belly
In some gyms, you occasionally see eager training partners punch the belly of their equally eager training partner while they hang on to a pull-up bar. Assuming this isn’t training for a combat sport, it does make for pretty poor ab hypertrophy training. Again, it is training the abs using isometric contraction, and getting repeatedly punched and the accompanying damage doesn’t exactly improve the stimulus to fatigue ratio for ab growth.
That wraps up the abs.
Reminder: if you’d like to see what effective ab programming looks like, check out the Ab Specialisation Template. For the first week, it will be 33% off!