Whether you do five or 500 a day, sit-ups are not going to get you the washboard abs you're hoping for - Joslyn Thompson-Rule tells us why

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If, like many people you’ve fallen victim to believing that doing 100 sit-ups a day is a fast-track ticket to Jessica Alba-like abs, then STOP. It’s. Not. Going. To. Work.

Contrary to popular belief, the rock hard nature of our abs doesn’t rest with how well, how often or how many sit-up exercises we can do - and, no matter if you do 50 or 500 a day - if they’re not combined with the correct diet and combination of other exercises, they will have little to no effect on the tautness of our tummies. Shocked? We were too, so we reached out to our Project Me Part 1 fitness professor and Nike Master Trainer  Joslyn Thompson-Rule  for the low-down on why sit-ups should be scrapped.

According to Joslyn there are a number of reasons why crunches aren’t all they’re cracked up to be, including how few of the total stomach muscles they actually work to address.

“Sit-ups only really deal with the external muscles,” says Joslyn. “They don’t do anything to build up the other areas of the stomach such as the transverse abdominis muscles (core) or the obliques. So essentially, just doing sit-ups alone won’t get you rock hard abs because you’re only working to strengthen one singular area, which is like trying to build the outer layers of a house with no foundations underneath.”

Not only do they leave little to no visible effect, but the particular focus sit-ups place on these selected muscles can also lead to damaging consequences on the rest of the body. “Physiologically increased amounts of sit-ups may exacerbate any tightness in the flexor chain (muscles along the front of the body),” says Joslyn. “This in turn can lead to a weak lower back putting pressure on the spine over time.” Indeed, researchers at the Texas Back Institute discovered that the ‘full flex’ movement - the actual ‘crunch’ part of crunches puts an unhealthy strain on the back at its weakest point. The section with the most nerves (and most potential for nerve damage) is in the back of the spine, which is the very part that bends and strains during a sit-up. Practising a range of movements that benefits all different muscle groups is essential to both back health and general athleticism.

Joslyn then goes on to explain that when it comes to our abs, the way they look has more to do with what we get up to in the kitchen rather than what we do in the gym. “What most people don’t realise is that the way our stomachs look has  90% to do with the food we eat  and our overall nutrition. You could do 1000 sit-ups a day and if your diet isn’t on point then you simply won’t shed any body fat. As we know diet is so, so important in all areas of the body, but it especially counts when it comes to the appearance of our tummies,” she adds.

MORE GLOSS: A Healthy Curiosity: Eat your way to better abs

So what, then, are we to do when on the quest for sleek and sexy surfboard abs? “Rather than doing sit-ups you need to work on moves such as planks, side planks and hollow holds (like a reverse plank on the floor), which work the deep inner core muscles, protect the spine and lower back and really help to pull the waistline in. By all means do still keep sit-ups in as part of your routine if you want - just make sure they’re part of a larger balanced training programme and healthy eating regime.”

For more fantastic fitness tips and tricks from Joselyn download our  Project Me Part 1 Guide . Offering 24 weeks of progressive workouts, a range of delicious recipes and a wealth of information and support from leading industry experts, it’s your one stop shop to a hot, happy and healthy body in no time.

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