There is a variety of types and causes of muscle cramps. One of the most common causes of muscle cramps is dehydration, but other causes include increased physical activity or lack of activity, stress, nutritional deficiencies and hormonal changes. The body may not be getting enough electrolytes, such as potassium or magnesium. Some other medical explanations include fibromyalgia, statin drugs, flu symptoms, hormonal changes and Lyme disease. Essential oils such as peppermint and cypress are ideal home remedies for muscle aches and pains.