What to do about Acute Muscle Cramping

Physical Therapy in Anchorage for Acute Muscle Cramps

Aches, pains, sprains, strains -- these are everyday problems for sports athletes. But there's one particular condition that may seem to be a minor problem but can cause debilitating sidelining. And that's something called exercise-associated muscle cramps or EAMC.

Exercise-associated muscle cramps presents with acute pain, muscle stiffness, and soreness. The muscles affected most often include the hamstrings, quadriceps, and calf. The muscles on both sides of the body are often involved. And on visual examination, it's possible to see a knotted up ball of muscle.

The symptoms don't occur at the time of exercise. The athlete is most likely to notice the muscle cramps after exercise. It can even be hours later. The tendency to develop these exercise-associated muscle cramps after exercise is referred to as the cramp prone state.

What causes exercise-associated muscle cramps? Who's at risk? What can be done to prevent them? Or treat them once they get started? Those are questions Physical Therapists who are also certified as athletic trainers are trying to answer. Although the problem has been recognized for the last 50 years, there has been no formal study/testing to find evidence-based answers to these questions.

That's why this group of Physical Therapists/athletic trainers performed a review of the literature to summarize what we do know and where to go from here. They searched all of the major publications from 1955 to 2008 looking for high-quality studies on this topic. In this article, they summarized what they found.

First, it's still not known what causes exercise-associated muscle cramps. Athletes of all kinds experience them -- including recreational and high-level competitive players. It doesn't seem to matter what type of sport the player is involved in. Climate (hot and humid) may be a factor. Dehydration and electrolyte imbalances are more likely during hot, humid outdoor activities.

The dehydration theory is the most commonly used explanation. But why does dehydration trigger exercise-associated muscle cramps? Sweat loss without replacing fluids adequately alters the balance of fluids and electrolytes (chemicals) in the body. Without the proper mix of calcium, potassium, sodium, magnesium, chloride, and others, the nerve endings attached to the muscles can't work properly.

When the nerve terminals are too sensitive, they set off a series of events that leave the muscles in a chronic state of contraction, unable to relax. That's when the muscle cramps become unbearable.

But this is just a theory based on observations of athletes suffering from muscle cramps in hot environments. The fact is, the same problem has been seen in athletes exercising in cool or temperature controlled arenas and gyms. So maybe it's something else -- like some athletes are just more susceptible because of the way their bodies function. Maybe there are crampers and noncrampers and that's just the way it is!

Some other interesting observations have been made about exercise-associated muscle cramping. Stretching the muscle seems to help relieve the cramp. Stretching doesn't affect the fluid and electrolyte balance. Replacing fluids is ineffective as well. So that leaves scientists scratching their heads trying to come up with reasonable alternative theories.

The next theory proposed is the neuromuscular theory. In this model, muscle overload during exercise results in an imbalance within the motor firing mechanism of the muscle. The feedback loop that tells a muscle when to contract and when to relax gets off-balance. An imbalance of impulses results in messages to the muscle to contract getting stuck. Stretching the muscle overrides the system and is like hitting the reset button.

Scientists have found it difficult to study this problem. Animal models (cats, rabbits) can't be used because they have different neuromuscular signaling mechanisms that don't match humans.

Working backwards (find a solution, then figure out why it's working) hasn't panned out either. People have used a wide variety of sports drinks, massage, electrical stimulation, changing exercise/workout intensity, and even drinking pickle juice! None of these seems to work equally for all people prone to muscle cramps or in the midst of an attack.

The one prevention and treatment technique that has consistently had the most successful results has been stretching. Keeping up on fluids and salt intake for athletes who seem prone to this problem is also still recommended -- even though direct evidence is lacking for this advice. And along with the recommendation to take in fluids and electrolytes is the reminder that these substances aren't absorbed right away. Athletes are frequently reminded to eat before you are hungry; drink before you are thirsty.

Finally, it's likely that exercise-associated muscle cramping is the result of a combination of factors. Until evidence-based experiments can sort out who should do what to prevent the problem, a multi-strategy approach is advised. Stretching, replacing fluids and electrolytes, and conditioning muscles affected most often are all advised. Strength-training, endurance, and plyometrics may help prevent neuromuscular imbalances and fatigue that set off inappropriate signals.

Reference: Kevin C. Miller, PhD, ATC, CSCS, et al. Exercise-Associated Muscle Cramps: Causes, Treatment, and Prevention. In Sports Health. July/August 2010. Vol. 2. No. 4. Pp. 279-283.