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This classic sit up exercise has been seen from everyone who ever watched Thai boxers train Muay Thai.
Although this sit up exercise is not a means to an end, it is a basic drill that will help with your abdominal conditioning for taking strikes.
To perform this exercise use a small size Thai-pad, preferably leather. Using a flat leg or bent knee sit up position perform situp as normal. On way down your partner will strike the abdomen area with the thai pad. To make this more difficult, the pad holder will stike downward with head of the pad just as if punching down into the stomach.