Why the ‘plank’ can be bad for blood pressure

PLANKING has been a staple in gyms and exercises such as yoga for years, and has seen a surge in popularity recently, with everyone from supermodels to the Prime Minister, Theresa May, doing it ( although Mrs May recently admitted to the Mail that ‘it was not her favourite thing’).

The appeal of the plank is that it helps strengthen and tone muscles all around your body.

It got its reputation as a supreme stomach toner after a study published in the Journal of Strength and Conditioning Research showed that it used 100 per cent of the abdominal muscles compared with 64 per cent used when simply doing sit- ups or crunches.

To plank, you lie flat on the floor and raise yourself to balance on your toes and elbows — keeping your back flat, you hold this horizontal position for as long as you can.

However, despite its benefits, experts warn that holding the pose for too long could be harmful.

The plank is a powerful exercise because the instability caused by balancing on your toes and elbows means you have to tighten your tummy and back muscles to stop your middle sagging towards the floor.

This requires the use of deeper muscles than most other abdominal exercises — ‘ muscles that include the pelvic floor, which supports the bladder, and the transverse abdominis, which support the back’, says Kate McTaggart, a personal trainer from The Transformation Coach in London.

OVERtime, working these deeper muscles creates a corset- like structure around the core of the body that not only leads to a flatter, more toned stomach, but also protects the back. If you’re doing it right it should also work the muscles in your arms, shoulders and gluteal muscles in the bottom too.

Being able to plank is also seen as a sign of physical strength, and gyms regularly encourage people to hold planks for five minutes, ten minutes or even more — the World Record is held by Mao Weidong, from China, who amazingly managed to plank for more than eight hours.

But longer holds might not necessarily be better. In fact, leading experts believe the perfect amount of time to hold a plank could be as little as ten seconds.

Doing it any longer may aggravate problems such as back pain.

‘You can increase the endurance of the abdominal muscles by holding a plank for ten seconds, relaxing then repeating the movement three times, twice, then once,’ says Stuart McGill, a professor of spine biomechanics at Canada’s University of Waterloo.

‘It’s the approach I use — and a far better approach for older people or those with back pain than holding it longer.’

Holding a plank for too long can cause pain, particularly if you have existing back problems. That’s because when your muscles tire, the stomach sags down and puts pressure on the lower back.

‘If you’re young and fit, I’d say do it for a maximum of a minute — longer won’t really give you any further benefits,’ says Professor McGill.

He does point out, though, that a plank is still better than sit-ups or crunches for people with back problems as it doesn’t bend the back like a hinge.

‘That’s like repeatedly bending a credit card over and over — eventually it will get brittle and break,’ he says.

Some experts also suggest avoiding holding the plank for too long if you have high blood pressure, as its static position raises pressure in the abdomen, a knockon effect of which is a further temporary rise in blood pressure, which could be harmful to those with heart or other circulatory problems.

‘ I’d also be careful if you are carrying a lot of extra weight,’ adds physiotherapist Tim Allardyce from Surrey Physio in Sutton. ‘ Increased mass around the abdomen can pull the tummy down, putting more pressure on the back.

FORheavier people, a kneeling plank where you balance on the knees rather than the toes might be a better option.’

Being able to hold a plank for more than 60 seconds can also be a sign that it’s no longer challenging you effectively, says Kate McTaggart.

‘Instead of adding time, vary the exercise to make it harder,’ she suggests. ‘Do side planks, where you balance on just one side of the body or lift one foot and/or one arm in the front position.’