Anyone who trains with me knows I don't do the conventional core exercises, a lot of research (Stuart McGill et al) show nowadays that conventional ab training: crunches, situps, rotational movements (such as the russian twist) actually have a negative impact on the spine as well as shortening your Rectus (RA) Abdominis (conventionally known as the abs).
As Mike Robertson states on his blog:
The RA has three primary functionsCorrect posture when training is essential, cues never involve a rounded back (thoracic kyphosis) as this puts the spine in a compromised position, it also reduces the scapulaes ability to get into appropriate positions which can lead to rotator cuff problems. When we do crunches/situps and back extensions (trunk flexion/extension) we are encouraging a posture that is detrimental, we need to spend a lot of time with clients correcting postures. Crunches shorten the length of the RA, it pulls down your ribs and by extension, shoulders further creating a rounded upper back. As Mike Robertson states:
The primary functions of your RA include:
- Trunk flexion/Resisting Trunk Extension
- Posterior Pelvic Tilt
- Transmission of “hoop” stresses. (Robertson 2010)
Mike Boyle has a great analogy here – it’s like a credit card. Bend a new credit card back and forth and, initially, it bounces back. But if you continue to bend that card, you eventually start to see a white crack. Continue to bend it back and forth, and over time that crack leads to a break. Your spine is not much different. (Robertson 2010)The RA (as well as the rest of the muscles of the core) is also designed to reduce movements around the lumbar spine (low back), it also transmits forces (from upper and lower body) as well as prevents movements. Core stabilisation training (planks, side planks, bridging) can help clients with low back pain as well as develop the core. As Mike Robertson states yet again:
Who needs crunches anyway?The point is when I program I am essentially designing ab programs that resist movement as opposed to promoting movement. The RA is innervated by the same nerve so you can't isolate upper or lower abs, instead we train for resistance rather than isolation. Ab rollouts/bodysaws, anti rotation presses, planks, all of these make up the bulk of my core routine as they are all exercises which train the abs to develop (hypertrophy) as well as training them in a way that is functionally accurate. That's part of the reason I also get my clients to lift heavy weights, aside from the fact that it has a raft of physiological benefits unrelated to the abs, it also causes the body to engage them in a stabilisation capacity, therefore developing them further.
Everybody and their mother can tell you that crunches train your “core.” What they may or may not be able to tell you is that you’re training spinal flexion.
First, it’s important to note where you’re getting your movement; a true crunch where your lumbar spine doesn’t move focuses on spinal flexion through the thoracic spine, or upper back.
People will obviously tell you that crunches spare the spine and isolate the abs. To an extent, they’re correct – when compared to a full range of motion sit-up, they probably are a superior option.
What people fail to discuss are the broader implications of performing a ton of crunches in their programming. Just because they aren’t hurting your back doesn’t mean they’re a great exercise.
From a global perspective, I can’t tell you how many people I see with jacked up shoulders and necks. Their postures often look the same – their head is carried in front of their body, their shoulders are slouched forward, etc. (Robertson 2010)
Ab Rollouts- There are several progressions for this exercise, beginners should begin with a rollout on a fitball. The rollout, due to its eccentric loading can be quite strenuous on the abs, specifically the lower abs (even with a common innervation DOMS can still be felt in specific areas of the RA), hence we reduce the load by raising the torso.
Plank/Side Plank- There seems to be some debate as to whether planks are great for hypertrophy for abs, to me it's irrelevant. Every client I get needs more stability around the trunk, they need to learn how to activate their glutes and the plank is a great beginner exercises to get them integrating the whole body into ab work.
Ab training is essential for better posture, strengthening the abs and if your bodyfat is low enough developing some additional definition. As explained above, the abs are primarily designed to resist movement, as such we train them accordingly. Exercises like crunches/situps/back extensions should be a thing of the past, there are enough progressions within the several exercises above to develop the abs functionally.
ReferencesRobertson M., (2010). Understanding Your Abs. Retrieved 22/04/2011. http://robertsontrainingsystems.com/blog/understanding-your-abs/
Robertson M., (2010). Understanding Your Abs.Part 2. Retrieved 22/04/2011. http://robertsontrainingsystems.com/blog/understanding-your-abs-part-ii/