Most of us are familiar with the idea that six-packs are made in the kitchen, meaning there’s no point slaving away over exercises that target your abdominal muscles if a poor diet is keeping them hidden by a layer of flab. However, if you have your diet sorted and belly fat is no longer an issue, you may want to do abs exercises in an attempt to develop and enhance the defintion of you six-pack. But what type of moves are the best?   

Core training improves stability, maintains mobility and reduces injury, say strength and conditioning coaches the world over – not to mention The American College of Sports Medicine. And of course, done correctly, it can produce a pretty awesome six-pack ready for beach season and who doesn’t want that?

But what’s the best training technique to activate the core muscles? Isolation exercises such as the standard crunch, or compound core exercises such as barbell rollouts or plank variations? A recent study conducted at Pennsylvania State University attempted to find the definitive answer – and the results could help you plan your summer abs routine.

Study background Compound movements such as plank variations are those that require ‘proximal limb’ muscles such as the deltoids and gluteals while activating the ‘primary trunk’ muscles (lumbar and abdominal). Isolation movements such as the standard crunch are those that only target the primary trunk muscles. Twenty healthy athletes were chosen to complete a series of core exercises while connected to surface electromyography (EMG) electrodes to monitor core muscle activation. Muscle engagement was measured during both isolation and compound exercises and then compared.

Results The figures showed activation of the abdominal and lumbar muscles was greatest during the compound movements. Specifically, the plank with reach exercise showed a 20% greater activation in the rectus abdominis muscle than the standard crunch. Anterior deltoid, erector spinae and gluteus maximus activation was also twice as great. This was supported by results that showed the compound side plank increased external oblique activity by 25% compared with the isolation side crunch.

Conclusion These results clearly show greater activation in the core muscles during the compound exercises. That’s not to say isolation movements aren’t without their benefits – if you are following a split training routine where you work different body parts on different days, for example, you may not always want to engage the proximal limb muscles, so isolation movements are ideal for this. But, if your goal is a strong, functional six-pack this summer, stick with planks and barbell rollouts.

Ross Edgley is a sports scientist at The Protein Works. For more information on The Protein Works products visit their website 

Ross Edgley is Co-Founder of THE PROTEIN WORKS™. A premium manufacturer of BCAA  power and pills.