I began getting cramps in my calves at night in late 2009. Attributed these cramps to the heat here in Texas. Admitted to the hospital in 2012 for stage II colon cancer. Leg cramps at night are a classic symptom of such cancer.I've always had problems with cramps even when I played sports. Now they seem to hit even more. My triceps lock up now and feel like someone is pinching the tar out my arms. No matter how much water I drink or potassium tablets. Still happens