Running is a high-impact activity that is a popular form of cardiovascular exercise. When you run many different things occur within your body. Your heart rate and respiration rise to meet the increased demand for oxygen and energy by your working muscles. Your body temperature elevates, causing you to sweat and lose fluids from your body. This can lead to dehydration and muscle cramps while you run.
Muscle Cramps
A muscle cramp is a sudden, involuntary contraction of one or more muscles in your body, according to MayoClinic.com. Often muscle cramps are temporary and not serious, although they can make it impossible to use the affected muscles while the cramp is occurring. They are usually caused by physical labor or exercise such as running, usually in hot weather. Running is a repetitive motion that dehydrates can lead to dehydration. If this occurs, you can get a muscle cramp in your legs while you are running.
Dehydration and Fluid Balance
Your muscles consist of up to 70 percent water, according to the National Strength and Conditioning Association. There are also electrolytes that are essential to your health and muscle function found in your body. When you sweat during your run, you lose not only water but also electrolytes such as sodium and potassium. While muscle cramps are painful and temporarily debilitating, dehydration and loss of electrolytes can lead to other serious conditions. Your ability to regulate your body temperature diminishes, which can lead to heat exhaustion, heatstroke or even death. It is important to prevent dehydration for muscle cramping and your health while running.
Recommended Fluid Intake
Drink eight to 12 cups, or 64 to 96 ozs., of water each day for normal function. With running, or any exercise program, you need to increase the amount of fluids you drink for adequate hydration, according to Clemson University. Drink two cups approximately two hours before running. Drink one to two cups 15 minutes before you begin running. Sip throughout your run, drinking approximately ½ to 1 cup of water every 15 to 20 minutes. If you are running outside in hot weather, weigh yourself before and after your workout. Drink 3 cups of water for every pound you lose through sweating. You can sip a sports drink if you sweat excessively and/or exercise for over one hour.
Other Considerations
If you are still having leg cramps during your run even though you are properly hydrated, consider that there may be another reason. Some medications can make you more susceptible to cramping. Overtraining and fatigued muscles may also contribute to leg cramps while running. Rest your body by taking a day or two off from running, and stretch your muscles to avoid and/or treat cramping.
References
- MayoClinic.com: Muscle Cramp
- "Essentials of Strength Training and Conditioning"; National Strength and Conditioning Association; 2008
- Clemson University: Fluid Needs
