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As Wikipedia says, the sit-up (or curl-up) is an abdominal endurance training exercise commonly performed to strengthen and tone the abdominal muscles. It is similar to a crunch (crunches target the rectus abdominus and also work the external and internal obliques), but sit-ups have a fuller range of motion and condition additional muscles.
I’m not a sporty person, however, I like sit-ups. I like them because if to do them correctly the result can be seen really soon.
I don’t like doing full sit-ups and there are several reasons why. First of all, I don’t think they’re really effective. Secondly, “Full sit-ups may cause back pain and arching of the lower back, increasing the risk of back injury”. That’s why usually I like to combine different exercises while doing sit-ups. For example, 25 for the upper side, 25 for the low side, 25 on the left and the right sides of my body.
At the end of Marathon, you’ll be able to see a comparison photo of my core before and after doing these exercises. I’m sure that combining them with a plank will be truly effective.
Yesterday in the evening, I did 3 sets of 25 sit-ups. Today I decided to do 1 set in the morning and 2 sets in the evening. In addition, as I wrote in the previous post, I continue doing planks 2 times a day, adding approximately 5 seconds of being in a plank each time.
P.S. Please, enjoy the video with 21 different variations of doing sit-ups.