It has replaced sit-ups and crunches, but there are better ways to build your core.
If any exercise were to claim bragging rights as the most hardcore, it would almost certainly be the plank. Beloved of the gym set, it has not only replaced sit-ups and crunches as the movement of choice for the midriff-conscious but has been elevated into a workout in its own right.
Competitive planking is rife. Not only is social media awash with plank challenges urging you to extend your core-clenching every day, but circuit sessions and bootcamp classes inevitably end with a plank-off among participants to see who has the greatest staying power.
Such is its air of superiority that an inadequate plank (40 seconds or less) ranks as the most shameful of gym failures, infinitely higher in the embarrassment stakes than admitting you can’t perform a press-up.
At its abdomen-ripping best, the exercise is reputed to tone the midsection like no other. Propping yourself up on your forearms and the balls of your feet, then holding the position for as long as you can is said to work all the muscles in your core. That includes the rectus abdominus — the “six-pack” muscles — transverse abdominus, internal and external obliques and the muscles in the hips and back.
Even the most reluctant gym-goer will concede that aesthetic returns for time output seem pretty impressive. Developing a washboard stomach from four to five daily minutes of quivering pain has to be worth the perseverance, surely? Yet not all experts are convinced, some expressing concern that the plank’s reputation is somewhat undeserved.
“It’s the new sit-up,” says Roger Kerry, the physiotherapist and associate professor at the faculty of medicine and health sciences at the University of Nottingham. “Everyone is focused on targeting their core and it’s seen as the best way to do it, but as an exercise in itself it has some less appealing issues.”
Kerry says that most people who do the plank are swayed by its high-profile image and links to seemingly body-protective forms of exercise such as yoga and Pilates. “They do it, but don’t really know why,” he says. “In theory, there are a lot of different fitness dimensions involved in the exercise — muscular endurance, strength, muscular control — but in reality it does none of them very well.”
As you tense, your pelvis sinks which strains the back even more
Kerry says that graduating from nothing to several minutes worth of planking in a week, as many do on a plank challenge, defies all principles of workout progression. “You would never run for a mile one day, two miles the next and seven miles after a week,” he says. “It is completely ridiculous that all sense is thrown out of the window when it comes to this exercise.”
Besides, even the muscles the plank is reputed to hone so effectively aren’t quite as impressively engaged as we have been lead to think. In research that was commissioned by the American Council on Exercise in 2014, and conducted at the University of Wisconsin-Madison, the plank was tested alongside a range of other exercises purported to be effective at strengthening the core, including the side plank and bicycle crunch.
Using electromyography, the exercise physiologist Dr Cedric X Bryant and his team first measured the baseline abdominal strength of the 16 male and female participants. Next they attached electrodes on the core muscles. They recorded their contraction as the various bodyweight exercises were performed and compared them with results for the traditional crunch.
The results seem surprising, particularly for those who gave up endless sit-ups with legwarmers. None of the moves elicited greater muscle activation than the traditional crunch and the plank and side plank scored significantly lower.
Dave O’Sullivan, the clinical director for ProSport Physiotherapy in Huddersfield, has long been convinced that there are better ways to develop a functional core. “People come into my clinic on a daily basis and tell me they have super-strong core muscles because they can do the plank endlessly,” he says. “But the range of muscles worked in the exercise is actually minimal. No matter how good your technique, the problem is that you are working the two big rods of muscle, the erector spinae, that run up either side of your spine when you do the plank. Your abdominal muscles aren’t dominating the movement at all.”
It’s not just that the plank has oversold its stomach-flattening ability. Worse than that, it could leave you with back pain. “Mechanically, it’s not focusing on the core, but is putting a huge load on the back,” says Kerry. “As you tense to retain the stability needed to hold the move, it is easy for your pelvis to sink towards the floor, which strains the back even more.”
Holding your breath exaggerates the tension in the lower back. “Even elite athletes stop breathing properly when they do the plank,” O’Sullivan says. “It exacerbates the rigidity that puts strain on the lower back and can be very destructive.”
If the plank has had its day, what is the alternative? O’Sullivan, who is working with the University of Huddersfield to study the phenomenon, says that core exercises should involve some dynamic movement. “More dynamic moves allow the abdominal muscles to lengthen and shorten without stressing the lower back,” he says. “It can be as simple as adding rotation or arm movement to a plank. Just avoid the basic front and side plank that require you to stay in one position for a prolonged time.”
Kerry says that emerging evidence shows “the involvement of the brain in changing the body’s direction and plane of movement” is also hugely important when it comes to exercising your middle. “You need to challenge yourself, challenge your muscles and your mind, by moving around as you work your core,” he says. “You are not going to get a god-like body in a week with anything, but a variety of movement is much more promising than plank-mania.”
Four alternatives to the basic plank
Assume a basic plank position then widen your feet apart. Reach forward with your right hand as far as possible, to 12 o’clock. Immediately reach back to 6 o’clock (between your legs), extending your arm as far as you can. Repeat to 3 o’clock, 9 o’clock and as many other “minutes” as you can manage before switching sides.
Start on all fours and begin moving along the ground as quickly as you can. Add variations, eg, move an arm and a leg from the same side of the body. Keep the hips straight and low (as if stalking something), then change to a high-level crawl. Continue for 2-3 minutes.
Assume a press-up position with your weight balanced on your hands, arms extended, and toes. Drive your right knee forward to the outside of your right arm, landing with the ball of the right foot. Spring back to the start position and repeat with the left leg to the left side. Repeat for 8-10 repetitions on each side.
Hang and swing
Find a tree branch that’s within easy reach. From a standing position jump up and grab it and hang for 15-30 seconds. As you get fitter, progress to swinging forward and backwards or from side to side.