“Electrolyte drinks prevent exercise-associated muscle cramps.”
Electrolyte drinks do not reliably prevent exercise muscle cramps.
Cramps often come from muscles working hard and getting tired, not just from missing salt. An electrolyte drink can delay a cramp but will not reliably stop one.
If a cramp hits during exercise, stop, then gently stretch and massage the muscle.
Talk to a healthcare professional if: your muscle cramps are severe, do not go away with simple stretching, keep coming back, or last a long time.
In the clearest test, 9 of 13 cramp-prone men still cramped while drinking an electrolyte drink, and a study of 210 Ironman triathletes found cramps were not linked to fluid loss or blood salt levels. Small studies show these drinks can delay cramps or make them harder to trigger, which is the small grain of truth, but the studies are small and short, so confidence is limited.
Electrolyte drinks do not reliably prevent exercise muscle cramps. In one test in the heat, 9 of 13 men still cramped while drinking an electrolyte drink, though their cramps started later.
In that 2005 study, 13 college-age men who were prone to cramps did calf exercise in 37 °C (99 °F) heat, once with a salted sports drink and once with no fluid. Nine cramped with the drink and 7 with no fluid; in the 7 who cramped both times, cramps came after about 37 minutes with the drink versus about 15 without. In a 2021 study of 10 men running downhill in the heat, an oral rehydration drink made it take a stronger electrical signal to trigger a cramp than spring water did; that is a lab measure, not real exercise cramps, and the drink's maker funded the study. In 210 Ironman triathletes, the 43 who cramped had similar blood salt levels and weight changes to those who did not; going faster and having cramped before predicted cramps. A 2019 review concluded that cramps likely have more than one cause and that no remedy works consistently. MedlinePlus, a U.S. government health site, says not getting enough fluids is the most common cause of cramps during sports and that sports drinks can help, but the studies above did not find dehydration or low salt to be the main driver.
- Jung AP, Bishop PA, Al-Nawwas A, Dale RB. Influence of Hydration and Electrolyte Supplementation on Incidence and Time to Onset of Exercise-Associated Muscle Cramps. Journal of Athletic Training. 2005;40(2):71-75. PMID: 15970952. PMCID: PMC1150229
- Lau WY, Kato H, Nosaka K. Effect of oral rehydration solution versus spring water intake during exercise in the heat on muscle cramp susceptibility of young men. Journal of the International Society of Sports Nutrition. 2021;18(1):22. DOI: 10.1186/s12970-021-00414-8. PMID: 33722257
- Schwellnus MP, Drew N, Collins M. Increased running speed and previous cramps rather than dehydration or serum sodium changes predict exercise-associated muscle cramping: a prospective cohort study in 210 Ironman triathletes. British Journal of Sports Medicine. 2011;45(8):650-656. DOI: 10.1136/bjsm.2010.078535. PMID: 21148567
- Maughan RJ, Shirreffs SM. Muscle Cramping During Exercise: Causes, Solutions, and Questions Remaining. Sports Medicine. 2019;49(Suppl 2):115-124. DOI: 10.1007/s40279-019-01162-1. PMID: 31696455
- MedlinePlus, National Library of Medicine. Muscle cramps. Medical Encyclopedia. Review date July 23, 2024