It is generally not necessary to supplement with magnesium unless you are deficient, as the data on using magnesium for muscle cramps and spasms in non-deficient individuals is conflicting. It is recommended to discuss this with your doctor during your next medical appointment. In the meantime, staying hydrated, warming up properly, stretching and massaging the affected muscle, and gradually increasing activity levels may help alleviate muscle spasms. Additionally, over-the-counter muscle relaxants like "Robax" may be worth trying, but be cautious about potential side effects and interactions with other medications.