The end of the sit-up

Forget everything you know about getting a flat tummy The old-fashioned sit-up is bad for your back — and your six-pack. Here’s what to do instead by Peta Bee for The Times T2 Tues 13th Nov ’18

Sit-ups were once considered an unrivalled standard of fitness; the number of abdominal crunches you could perform was a measure of your macho strength. Yet if you are one of those who struggle to haul their body off a gym mat to touch elbows to knees, then there’s good news: the sit-up’s reign of exercise supremacy is over.

Last week the British Army revealed that it is to drop the exercise from its fitness tests after a scientific review of basic training methods suggested that the two-minute sit-up challenge used for two decades is outdated. Working with physiologists from the University of Chichester, the army has introduced a new set of tests, which it says are “gender and age neutral” and of more practical use for recruits. “I’ve got plenty of combat experience, but I’ve never done a sit-up on the battlefield,” Field Army Sergeant-Major Gavin Paton said. Canada dropped sit-ups from its military fitness test nearly three years ago and the US army announced in the summer that it will roll out a new, improved test — minus sit-ups — by October 2020.

The fall from favour of sit-ups is a result of growing evidence that not only do they fail to spot-reduce body fat or give you a strong core and six-pack, but they pose a potential hazard to the spine. Among the exercise’s most outspoken critics is Stuart McGill, professor of spine biomechanics at the University of Waterloo in Canada and the author of more than 400 published clinical papers on spine health. He has suggested that sit-ups can put hundreds of pounds of compressive force on the spine. In his studies he has shown that there’s a statistically higher risk of developing a back problem if the spine is repeatedly put under force from muscles contracting to hold it in a bent position, precisely as it is in a sit-up.

“When we’ve measured the loads on the spine with each sit-up, they were right on the limit noted by us and orthopaedic experts as causing damage over time and with repetition,” McGill says. “Our research certainly justifies avoiding sit-ups as part of an exercise routine for a healthy spine.”

Dr Richard Blagrove, a strength and conditioning researcher at Birmingham City University’s school of health sciences, says that he wouldn’t recommend sit-ups even to the elite athletes he advises. “Although our spines can flex and extend as part of normal movement, the intervertebral discs don’t like repeated patterns of flexion or hyperextension,” he says. “That’s why exercises like sit-ups, lateral bends and back extensions are contra-indicated for back health. I would avoid them, instead prioritising the muscles that play a role in supporting the spine, which include the gluteals and hip flexors.”

Far better for your back and body, he says, are moves that strengthen the musculature around the spine such as the barbell squat and deadlift. “Exercises like plank holds, cable chops and lifts, and rollouts are good trunk-muscle exercises, with the aim being to adopt a good posture to use the shoulders and hips, joints that are designed to remove stress on the lower back.”

It’s an argument that has filtered down to the gym industry, where sit-ups are increasingly blacklisted. Part of the problem is that the exercise focuses on strengthening your rectus abdominis (the abs or six-pack muscles) at the expense of others in the trunk area. “Muscles work in antagonistic or opposing pairs and when one muscle contracts the opposite relaxes,” says Adam Hewitt, master trainer at Ten Health & Fitness in London. “When you perform a sit-up, you are contracting the rectus abdominis, but you need to work the opposing muscles to your abs, which are the multifidus and erector spinae to achieve core strength.”

Dalton Wong, the director of the private London gym Twenty Two Training, whose clients include Jennifer Lawrence and Kit Harington, says he rarely uses them with any of his clients. “They mainly work your upper abdominals and, combined with tight hip flexors from too much sitting, can encourage a rounded back,” Wong says. “Poorly done sit-ups can also lead to head and neck strain, all of which is bad news for the spine.”

Not everyone thinks sit-ups should be avoided. Matt Todman, a physiotherapist who is the director of the Six Physio chain of clinics, says that sit-ups can be modified so they are less risky to your back and more effective for gaining a six-pack. “Nobody should make sit-ups their sole core exercise, and sit-up challenges are always a bad idea,” he says. “If a sit-up hurts in any way, it is not good, but you can adapt the exercise by lifting your feet off the ground or using a stability ball to reduce the pressure on your spine.”

A 2011 review paper by New Zealand researchers found that sit-ups did help to improve flexibility and muscle strength to some degree. However, they recommended limiting the exercise to 15 repetitions to start with. Another study around that time showed that people who did a sit-up routine daily for six weeks experienced no significant improvements in waist size or fat levels around their middle.

“Too many gym-goers still focus obsessively on sit-ups and the like, causing muscle imbalances which manifest as increased pressure on your back and spine,” Hewitt says. “There’s now a better mix of exercises that will not only help you obtain well-defined abs, but will also support your spine and improve your core strength.”


The personal trainer

Dalton Wong, director of Twenty Two Training (

“Resistance-based exercises, such as the deadlift, pull-ups, squats and push-ups, require a strong torso to support the arms and legs so are great for developing the core,” Wong says. Or try the bicycle crunch. Lie on your back on the floor. Raise your legs and bend your knees so that your calf muscles are at right angles to the floor; raise your arms in the air. Extend your left leg out in front of the body, then return to the start position. Repeat with the right.

The physio

Matt Todman, director of Six Physio (

“There are lots of ways that you can modify a sit-up to suit your body,” Todman says. “Don’t think you have to perform the full, traditional exercise, but try a shorter range of movement or raise your feet off the floor.” To do the raised-leg sit-up, lie on your back and bring your hands behind your head. Raise your feet off the floor and bend the knees at 90 degrees so that calf muscles are parallel to the floor. Exhale and crunch up without letting your chin drop into your chest. Inhale then lower back down and exhale.

The Pilates instructor

Adam Hewitt, master trainer at Ten Health & Fitness (

You need to mix up sit-ups with cat-cow stretches, bird dog exercises and planks. Or try the Superman exercise. Lie face down on a mat with your arms stretched above your head (like Superman). Raise your right arm and left leg about 10-12cm off the ground (or as far as you comfortably can). Hold for 2-3 seconds and relax. Repeat with the opposite arm and leg.

An alternative version is to start on all fours in a table-top position (with hands under shoulders and ankles beneath knees) and then engage abdominals to extend your right arm and leg, both parallel to the floor. Hold for a couple of seconds, return to the start position and repeat on the other side.

The scientist

Stuart McGill, professor of spine biomechanics at the University of Waterloo (

McGill recommends the modified curl-up. Lie on the floor with your hands palm-down under the lumbar region of the back (the hollow). Raise your elbows slightly so that they aren’t touching the floor and brace the abdominals. Raise the neck and shoulders off the floor without using your hands and without straining. Hold for a count of 8-10, then lower back down. Start with five repetitions, rest for 30 seconds, then three repetitions, rest for 30 seconds, then one repetition. Throughout the exercise you should brace the abdominal muscles rather than hollowing or sucking them in, to ensure you have a stable core.

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