@JamesBon92007, Yes, if your potassium levels can be tested with a blood test. Cardiac muscle has some special physiological properties compared to skeletal muscle, but the basic electrophysiological process governing contractions is the same for both muscle types. If your potassium levels are low enough to generate muscle cramps then you may very well experience cardiac arryhmias as well. People tend to attribute muscle cramps to potassium levels far too often. The bigger contributor to muscle cramps is simply fatigue. We store fuel (glucose in the form of glycogen) that is used for energy production (ATP) in muscle cells. Once the muscles have used their stored energy, they can tap fatty acids and glucose from the blood to continue ATP production. Even in the blood stream, however, that fuel supply is limited and/or may not be transferred fast enough enough to generate ATP inside hard working muscles. When ATP levels in the muscles drop, the muscles tend to be unable to release and a cramp ensues. This is one of the reasons that things like coconut water and bananas are helpful, they simply supply a lot of sugar