Patient: Hi, when performing a bicycle crunch do you burn more calories if you extend the leg as close to the floor as possible or if the legs are extended higher up off the floor. Or does the level of the feet off the floor not really affect calories burnt. Also, what height and angle do you have to crunch the leg and knee up to in order to burn calories. Do you have to crunch the leg up to the 90 degree position or 45 degree position to the chest in order to burn calories. Finally, i sit the height of the leg being raised to the chest or the closeness of the leg touching/ pressed into the chin that burns calories and does fully extending/ straightening the other leg burn more calories while the other leg is being crunched. And, do you have to crunch the leg and knee up into the armpit with the knee being bent at a deeper angle in order to burn more calories. Thankyou for your help and kind regards,Kelly.
Doctor: Hello,Thank you for your medical query at AskTheDoctor.comI understand your concern.When you are doing a bicycle crunch it is very important that your back is firstly off the ground. A lof of people start the crunch with their heads up, and slowly with increasing counts, their back touches the ground which does not help.You burn more calories when the legs are extended higher up off the floor.The leg and the knee should come until you feel a squeeze in the abdominal muscles, making it really tight, you can bring the knees as close to your upper body as you can. That is the best form of doing it. Regarding burning more calories, it depends on the duration. More crunches help in burning more calories, provided the form is fine. 90 degree position is better than 45 degrees.You need to fully extend the other leg while the other leg is being crunched for maximum impact.It is very difficult to extend all the way to the armpit, but if you can, you will burn more calories.Hope this was helpful,Feel free to discuss further,Regards.