Hello, Thank you for your query. I m Dr. Shuba Hariprasad and will be answering your query today. This could either a severe muscle pull or could be something more serious like a blocked vessel in your leg. As your whole leg cramped, I would like to check for sciatica (due to spinal nerve compression) *how old are you? *what is your height and weight? *do you smoke or consume alcohol? *do you have any other medical issues or take any medications? *what is your daily activity level like? *any swelling or change in color in your leg? I recommend : - a physician consult -blood tests (complete blood count, lipid profile, blood glucose levels, kidney and liver function tests, clotting profile) -doppler study of both the legs -xrays of the spine. Mri if nerve compression is suspected. Based on these, we can arrive at a diagnosis and treat accordingly. In the meantime, apply ice and warm compresses on your affected calf. Avoid exercise till this resolves. Hope this helps. Wish you good health