A charley horse is caused by a sudden, involuntary muscle spasm or cramp, often occurring in the legs or feet. Several factors can trigger these painful muscle contractions:
- Dehydration or loss of body fluids through sweat
- Overuse or excessive exercise of a muscle
- Lack of stretching before physical activity
- Electrolyte imbalances, especially low levels of magnesium, potassium, calcium, or sodium
- Poor blood flow to the muscles
- Being active in extreme temperatures (hot or cold)
- Nerve irritation or compression, such as from a herniated disk or spinal issues
- Certain medical conditions like kidney disease, diabetes, thyroid disorders, or pregnancy
- Side effects of some medications, including diuretics, statins, asthma drugs, and others
- Stress and poor posture
Charley horses can also occur during rest or sleep without obvious triggers. They are more common in older adults, athletes, pregnant people, and those with underlying health conditions
. In summary, charley horses result from muscle overactivity, electrolyte disturbances, nerve issues, or other health factors that cause muscles to contract uncontrollably and painfully
