Nirawyn said:
I would like to know which are the stretched muscles used to do the splits with one leg in front and one leg behind
Answer: Your leg muscles.
There are many muscle groups involved in stretching the legs, large and small, all the way from your toes up around your buttocks.
It does not matter the name of the muscle (a muscle by any other name would stretch the same). As for the name of the splits, in the past, many people in the U.S. have discriminatingly called the center splits, or side splits (with body facing front, and both legs stretching to the side) the "Chinese Splits," and the ones where you have one leg forward and the other back, the "American Splits." I never have cared for these terms as they suggest that anyone who is non-Asian can not do the Side-Splits).
Always do some warm-up exercises (jumping jacks, push-ups, sit-ups, etc) before stretching to relax the muscles.
Then, just spread your legs apart in the splits - the muscles that you feel resisting, are the ones that you need to stretch. Stop when you feel an "uncomfortable" stretch - - not pain or a burning sensation! Hold a good stretch for 10 seconds, then release the pressure. Do not bounce, or do any rapid movement in a stretch as this can cause injury, and will cause your muscles to reflexively retract, preventing a good stretch. The knees should
not be bent, but do not "hyper-extend" them.
Stretch in the splits in each position (side or center splits, left leg front split, and right leg front split) with your hands off the ground, then again with your hands supporting part of your weight. Also, stretch one leg at a time while on your feet, and while sitting, then stretch with both legs extended. After sitting stretches, stretch while standing on one leg with the other leg propped up high on a support.
It is very important to stretch the first time through with light, warm-up stretches (10 - 15 minutes), work up a good sweat on a bag, doing forms, or other training, then go back through an entire, very thorough stretch routine (30 minutes to an hour). Do this every fourth day, with the three days in between performing a light, maintenance stretch routine.
In case you are wondering if I know what I am talking about, here is a picture of me stretching this year.
(age 46)
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