Cramps

Cramps are spasmodic, painful, involuntary muscle contractions. This page is focused on Exercise Associated Muscle Cramps (EAMC), though there are other types. Many runners suffer from cramps, and sometimes cramps can be severe enough to prevent the completion of an event, or catastrophically impact performance. What causes cramps and how can they be prevented? While there is no 'magic bullet', there are some promising possibilities to try that have few downsides.

Contents

1 Hydration and Electrolytes

The evidence for hydration and electrolyte status causing cramping is somewhat ambiguous. A study of the 2000 South Africa Ironman Triathlon showed no correlation with dehydration or electrolyte levels with cramping, though cramping athletes did have slightly lower sodium concentrations. A study in 2005 showed that a carbohydrate/electrolyte drink delayed cramps in athletes that have a history of cramping. There is also evidence that even small amounts of pickle juice can help limit cramps. Coaches often recommend pickle juice for athletes who suffer from cramping.

2 Altered Neuromuscular Control & Stretching

There is some support for the idea that cramps are neurological in origin. Altered neuromuscular control means that there is a disruption of the nervous control of the muscle, rather than a problem purely with the muscle itself. There is some evidence that muscles that are cramping have a higher level of electromyographic (EMG) activity and that a return of the EMG level to baseline correlates to recovery. The level of EMG is also reduced by static stretching, which has lead to an interesting theory. This theory is based on the idea that a cramping muscle loses its inverse stretch reflex. This inverse stretch reflex is stimulated by a prolonged stretch and causes the muscle to relax. If a muscle’s inverse stretch reflex becomes weakened, it will tend to contract strongly. The theory also explains why cramps are more likely to occur in muscles that are contracting in a shortened position (calf, hamstring). This theory suggests that stretching will help with cramping, not because of increased flexibility, but because it will reinforce the inverse stretch reflex. This theory also suggests to me that runners whose muscles are not fully extending while running may be more prone to cramping, but I have seen no mention of this elsewhere.

3 Exercise Level

Cramps are more common in runners who go further or faster than they are accustomed to. There is a belief that cramping is related to exhaustion of the cramping muscle, rather than overall fatigue. Higher levels of training may help prevent cramping.

4 Heat

It has been widely noted that cramping is more common in hot conditions. While this does not directly offer a way of preventing cramping, it is possible that Heat Acclimation Training may help.

5 Hypokalemia

There does appear to be a link between Hypokalemia (low potassium) and cramping, but is actually very unusual without medication or a serious medical condition such as kidney problems or AIDS.

6 Recommendations

There are no guarantees I can make, but here are some suggestions that may help.

• Ensure you have adequate sodium and electrolyte levels, as well as good hydration before starting to run.
  • I would recommend consuming salty foods and drinks between runs. Personally I drink water with added salt at a ratio of 1/4 teaspoon table salt to a quart of water several times a day when the weather is warm. I also add salt to my salads and other food, aiming to add at least 1-2 teaspoons of table salt each day. I use my taste as a guide as well; if salty food appeals, I eat salty, but if salty tastes bad, then I don't bother.
  • Try consuming pickle juice before and possibly even during runs.
• Train so that your race is not beyond your capability.
• Stretch regularly using static stretching.
• Perform Heat Acclimation Training for races that may be warm
• Stay hydrated; it won’t help with the cramping, but it’s still important! Practical Hydration