Understanding Muscle Cramps

"Understanding Muscle Cramps" was written by Dr. Kevin Sprouse. Dr. Sprouse is a team physician for the EF Education Easy Post Pro Cycling Team. He has a degree in exercise science and has board certifications in both Sports Medicine and Emergency Medicine. He practices at Podium Sports Medicine in Knoxville, TN.

Muscle cramps have ended many an athlete’s race, and the questions I always get are “why did this happen?” and “how do I keep it from happening again?” For many years, medicine and science had no good answers to these questions. But in the past few years, the science has truly evolved. As tends to happen though, those answers have led to more questions. Once we know why cramps happen and how to stop them, should we? Is it healthy to turn off this natural response?

In recent years, some very important academic work has shown that we were wrong about cramps. There is actually very little correlation with hydration or electrolyte status. More important are variables like genetics and fitness. This helps explain why we’ve seen so many “salt” products come to market, only to fade away after a few years. These recently published studies have shown that there are neurologic receptors in the mouth which act to interrupt the cramping response. If you stimulate those receptors with the correct substances, you can abort and possibly prevent muscle cramps to some degree.

You may have heard of athletes using Pickle Juice Shot or salt licks to “cure” cramps. There is a reason such home remedies have persisted in athletic lore. These things probably work to stimulate the oral receptors, and may serve to stop the cramp contraction. In fact, the scientists who discovered these receptors have even created their own product designed to do this same thing.

But every person is individual. I have seen other remedies that do work for certain athletes, and they often arrive at their own, personal fix after years of trial and error. While writing this article on the Cannondale Pro Cycling Team bus at the Criterium du Dauphine, I polled the riders to see what they’ve found useful for them. Repeatedly mentioned was magnesium.

This mineral is used by the body for many processes, one of which is muscle relaxation. In my practice, I routinely measure athletes’ magnesium stores, prescribing supplementation when needed. Not everyone needs it, so it’s not an appropriate remedy for all athletes who cramp. But I do find that it can work when used in a targeted manner.

The other preventive strategy that was mentioned by these pro cyclists was weight lifting. As muscular fitness has been shown to be directly related to cramping incidence, specific workouts can help to decrease an athlete’s propensity to cramp during a race. The fitter the muscle, the more work it can handle, and the less likely it is to seize up under heavy load.

Should we push past this?

With all these ways to address cramping, another question has arisen. Is it even healthy to concoct a way to push past the cramps? Are muscle cramps a protective mechanism and, therefore, a message from the body which should be heeded?

There are no good studies which have addressed this question, but perhaps it is the next frontier in cramp research. Given this lack of objective data, I’ll let you know what I think.

The Central Governor

Perhaps a corollary can be found in the “Central Governor Theory” of performance, as proposed by Dr. Timothy Noakes. The idea here is that a major limiter of performance, especially in an endurance endeavor such as running or cycling, is the brain’s innate neurology rather than cardiovascular physiology. Fitness certainly separates the couch potato from the Olympic 5000m champion, but the difference between the winner and losers in Rio might be their ability to turn off this “Central Governor” and convince the brain that they are not actually in physical danger. The “Central Governor” is likely an evolutionary remnant that is less pertinent to our health now that we have abundant food and recovery techniques and are not being chased by lions.

In the same manner, if we assume cramps are a protective mechanism, it is unlikely that we face the same dangers in sport as our ancestors may have faced when simply trying to survive. If cramps once served to regulate our efforts and protect us from the dangerous state of fatigue, we’ve now evolved past the point where that is relevant.

Separate from this argument though, I would propose that cramps are not protective at all. In fact, they are quite damaging to muscle tissue. Sometimes they even occur early in a race, when very little effort is being put forth. In medicine, a cramp is termed a “tetanic contraction”. In such a circumstance, many muscle fibers are firing and there is an inability to relax. When this happens, muscle cells are damaged, releasing measurable proteins into the blood stream. It is very easy to argue that the cramp may be more damaging than the endeavor during which it occurs. Just think back to the last time you cramped in a race. I’m guessing you were sore in those muscles for days afterward. It is a destructive process!

Cramps are a natural part of training and racing, and some people are genetically doomed to experience them more often. However, with recent scientific discoveries, we are learning more about why they happen, how to prevent them, and how to stop them when they occur. I think learning how to control and abort your cramps is beneficial to both your health and your performance. You can always cross that line and push too hard, but I don’t think muscle cramps are an inherently helpful mechanism. Maybe future studies will prove me wrong, but I doubt it.

A great place to start in preventing cramping is with proper hydration. Check out our Hydration Drink Mix Sampler and find the mix that works for you!