Patient: Hi, when performing a bicycle crunch what is it that determines the calories burnt. Does the crunching up of the quadricep muscle in the leg have to be as high up to the chest as possible in order to burn calories, or does contraction of the quadricep occur from the straigthened/ start position throughout the movement of raising the leg up to the chest. Does contraction of the quadricep muscle in the leg burn calories no matter how small in length the contraction is or do i have to make sure the leg is moved a long distance throughout the bicycle crunch in order to burn calories. Also when the leg is raised as high to the chest as possible in a bicycle crunch does this result in the quadricep muscle contracting to a longer length and does the leg being raised as high to the chest as possible build and define the quadricep muscle more. Im looking for an accurate and detailed answer for a health and fitness report im writing, thankyou for your help and kind regards,Kelly.
Doctor: Hello,Thank you for your medical query at AskTheDoctor.comSo, when we are doing a bicycle crunch, the calories sta rt burning no matter how many times we do it, as it is considered to be one of the high-intensity workouts. But the issue is a lot of people do it in a wrong way, ending up burning very little calories. The rule is your head should be slightly up from the ground when you are doing the crunch, as this provides the abdominal muscles further scope to expand. You definitely need to crunch up the quadricep muscle very close to the chest, and try doing 20-30 repetitions per minute. There are contrasting views on the count in a minute, however, very fast crunching also does not help as the balance is not maintained properly. So ideally, a count of 20-30 crunches should be done, and the leg should be crunched up as close to the chest as possible. The rule is your hand should be behind the head, and as you are crunching up your elbows should be able to touch your legs. So, that is how close you should be crunching.For the second part of your query, yes, it definitely gives the quadricep muscle a better shape and allows it to build more by contracting more. For abdominal muscles, the more you are able to squeeze the better the muscles get.Hope this was helpful,Feel free to follow-up.I am always glad to assist you.