Knee flexion occurs from the muscles on the back of your leg – your hamstrings and calves. However, the bulk of knee flexion strength and power comes from the hamstrings.
If you get a hamstring cramp in this class, it’s not because you’re dehydrated (If you are dehydrates, then go grab some water!) – it’s because your nervous system doesn’t know how to control this unfamiliar end-range of knee flexion.
Work just below the cramping threshold and with time, the cramping will be no more!