Muscle cramps are rather common as approximately 60 percent of adults experience these oftentimes painful involuntary contractions according to the Medical University of South Carolina. Additionally, the rate of cramping tends to increase with age. Though muscle cramps are typically harmless and usually go away on their own, Medline indicates that stretching, massage, heat, and increasing fluids can sometimes help. So too can supplements. Here are three to consider based on scientific research.