I did 500 bicycle crunches every day for a week — here’s what happened to my abs

a photo of a woman doing bicycle crunches
(Image credit: Shutterstock)

A bicycle crunch is a classic ab move that can be done lying on your back on the floor using just your body weight. Don’t let the fact this is a bodyweight exercise put you off — when done with the correct form, it really does create a serious core burn.

Imagine the motion of cycling whilst lying flat on the ground, and you’ve essentially mastered the bicycle crunch. Although it might sound simple, as a personal trainer, I often see people doing this move incorrectly, which can lead to back and neck pain. That said, if you do this move properly you can reap so many benefits.

To learn more about the exercise and its benefits, I decided to make a challenge out of the bicycle crunch by doing 500 reps (that’s 250 on each side), every day for a week. Read on to find out what happened.

The benefits of a bicycle crunch  

I love a bicycle crunch, and when they’re done properly, this exercise is great for targeting the obliques — the muscles that lie down the sides of your core — as you crunch your knee and opposite elbow together. But it’s not just the obliques that are targeted. The six-pack muscles, aka the rectus abdominis, are also targeted as are the deeper core muscles — the transverse abdominis. 

In fact, you get some serious bang for your buck with a bicycle crunch. A study published in the American Council on Exercise cited bicycle crunches as one of the most effective exercises to do for your midsection. 

A strong core might be important to you for aesthetic reasons, but it’s also essential for everyday movement. Plus, it can help with other sports and exercises and can help prevent your spine from injury too. 

Let’s not forget that bicycle crunches can also become a bit of a cardio exercise if done at pace, getting your heart rate up. 

How to do a bicycle crunch 

an illo of a woman doing bicycle crunches

(Image credit: Shutterstock)
  • Lie flat on the floor, pressing your lower back into the ground.
  • Bend your knees, place your feet flat on the ground, and put your hands behind your head, with your elbows wide.
  • Lift your feet off the ground so your knees are at a 90-degree angle and as you straighten your left leg out in front of you, with toes pointed, crunch your abdominal muscles, lift your shoulders off the ground, and bring your left elbow to meet your right knee.
  • Then, as you bring your left leg back to bent, straighten your right leg, and bring your right elbow to meet the left elbow, crunching through the core.
  • Keep repeating this movement, alternating sides and focusing on keeping your lower back on the ground.

Want to make it harder? Slow the move right down, or add a set of the best ankle weights for extra resistance.

I did 500 bicycle crunches every day for a week and this happened 

I slowed some down

Slow and controlled is the way forward if you want to increase that core burn and make muscles work harder. After all, time under tension is the secret behind muscle growth. 

So, as I was doing my 500 bicycle crunches, I took the time to slow down occasionally. Don’t get me wrong, there’s no chance I was doing all 500 at this pace, as I’d have been there all day and the ab burn would be too intense — but every 50 reps or so I decided to just half the tempo for 10 reps. 

Tuck your tailbone!

Whenever I do Pilates (my new favorite exercise of 2023), I am always reminded by the instructor to tuck my tailbone so that the base of my spine is touching the mat. Usually, there’s a small arch in the lower spine but to engage the lower ab muscles and stop back pain, it’s wise to tuck your tailbone so that the bottom of the spine is flat against your exercise mat. 

I found that doing this during bicycle crunches certainly makes a difference. Not only did I engage with my lower abs, but I felt the burn far more intensely throughout my 500 reps. It does make the exercise harder but if you want an exercise to work, then you need to be engaging all the muscles. 

It’s easy to lose your form

I’ve already explained what a proper bicycle crunch should look like, but holding this form for 500 reps is no easy feat. It’s easy for your form to deteriorate as the body tires. I did try my best to maintain proper form — this meant focusing on extending my leg out straight whilst the other leg came in to meet my opposite elbow. 

Maintaining good form also meant my elbows staying wide, rather than bowing in, pulling on my head. Rather, it’s the core that’s doing the work to crunch your torso upwards, not your neck. 

I felt this deep in my core

There’s ab burn, then there’s the deep, inner core burn that comes with 500 reps of bicycle crunches. It’s at this point that I feel like I’ve nailed it and I’m targeting my entire core. Other exercises that I find elicit the same burn include leg raises, hanging leg raises, and any Pilates-based exercises. I did feel this in my obliques however for me, this was definitely more of a ‘deep core and six pack’ exercise.

I broke up my reps

When I agreed to do this challenge, I knew that 500 reps was a lot, and as the week went on, I soon got bored of this exercise. I tended to break up my 500 bicycle crunches into groups of 50 to 60 reps, just to make it easier and to ensure that I held good form.  A quick little break gave my muscles a breather to recover so I could go back in strong. 

I will add that 500 reps took several minutes, even by the end of the week — this isn’t a speedy challenge if you’re looking for an ab blast.

I did 500 bicycle crunches every day for a week — here’s my verdict 

While I definitely noticed a really burn in my core, I’m glad this challenge is over, and I wouldn’t do 500 bicycle crunches in one go every day. It’s a lot and it tires out the core muscles which means your form can deteriorate, putting your lower back and neck at risk of injury. That said, I love this exercise as it targets all of the major muscles in your core, but doing fewer reps is enough to reap the rewards. 

I recommend adding bicycle crunches into your workout routine — they are an excellent ab exercise, and they require zero equipment so you can do them anywhere, anytime. 

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Lucy Gornall

Lucy is a freelance health and fitness journalist as well as a pre and post-natal personal trainer. Although a sweaty gym session (skipping rope is a must) is her favorite way to ‘relax’, she’s also a fan of bingeing on The Office, snacking on chocolate-coated raisins, and fizz-filled brunches with friends.