Muscle Cramps: Why Most of What You’ve Heard is False

Let’s look at what causes cramps (HINT: most of what you’ve heard or read about the cause of cramps is probably not correct) and what you can do to avoid and/or treat them (HINT: most advice you’ve heard or read on this topic is also incorrect or incomplete). Let’s also look at why bodybuilders seem to be more susceptible to cramping as their body fat decreases leading up to a contest. 

By Mark Gilbert, B.Sc. (Nutrition), CISSN

Most of us, especially if we play sports or work out regularly, have experienced a muscle cramp. In fact, even most people who are fairly inactive have had a muscle cramp at some point or other. If you’re lucky, your experience with cramps felt like a sudden tightening of one of your muscles for a few seconds that was a bit uncomfortable. If you haven’t been so lucky, you may have had a cramp that felt like the muscle was contracting so hard that it was going to tear off the bone which lasted several seconds or even minutes. Some unfortunate people have these quite often!

The majority of reported cramps occur in the calves and hamstrings, but they can happen in any muscle and, from my experience working with people and training in the gym, physique athletes quite often also experience them in the pecs, quads, and abs. Of course, most of what has been written about cramps relates to endurance athletes like long-distance runners and triathletes, but as most people who have worked with physique athletes know, a substantial number of these guys also get cramps at some point, especially as they get leaner and closer to contest time. They are often severe enough that they interrupt or even end workouts completely. Many bodybuilders have experienced severe cramping on stage, which has literally left them on their backs, including the current Mr. Olympia, Phil Heath. It can really be a problem and, if you haven’t had one, there’s a good chance that some day you will.



Athletes and gym-goers often get cramps when they are perfectly hydrated and exercising in moderate and even cool environments, and sometimes at the outset of exercise.


Does Dehydration Cause Muscle Cramps?

Just about every article you read or ‘expert’ you listen to will tell you that EAMC (Exercise-Associated Muscle Cramps) are caused by dehydration and electrolyte (sodium, potassium, magnesium, etc.,) imbalance. Of course, this does at first seem to make perfect sense. These cramps do tend to happen in hotter environments, when people are sweating out water and electrolytes. Also, diuretics (drugs that cause you to shed water) have famously caused hundreds of bodybuilders to cramp up, shake violently on stage, and in the days leading up to contests. Unfortunately, the circumstances of some cramps and the vast majority of published research now indicate that dehydration and electrolyte imbalance are, at best, only ‘potential contributors’ to cramping and are not necessary pre-conditions to its occurrence.

As an example, athletes and gymgoers often get cramps when they are perfectly hydrated, in moderate to cool environments, and even early in their workouts. A thorough review of all of the scientific literature conducted at North Dakota State University concluded that the evidence that dehydration and electrolyte depletion caused EAMC was weak. This review also noted multiple studies showing that fluid and/or electrolyte loss from the body did not correlate with a higher rate of cramping. Furthermore, the most recent review, carried out by scientists at the University of North Florida, not only came to the same conclusions about dehydration and electrolytes, but they have also proposed a much more feasible explanation.

What Really Causes Muscle Cramps

The one thing that most researchers in this field now agree on is that EAMC has more to do with effects on the nerves, not so much by the depletion of blood to the muscles. Based upon this, sports scientists at the Exercise Science and Sports Medicine lab at the University of Cape Town propose that there are two main factors at work here. Simply put, one cause is likely simple muscular fatigue or damage, which is known to cause irregular misfiring of the nerve. The second and primary cause is that there is an imbalance between the mechanisms that excite the nerves and the counter-mechanisms whose job it is to relax them.

Specifically, there is a ‘stimulatory’ cellular structure along the centre of each muscle fibre called the ‘spindle’. Its job is to fire the muscle at the appropriate speed and force to do the correct amount of work that is being asked of it. The spindle signals the force of contraction in cooperation with a sensory receptor located on the muscle’s tendon, called the ‘Golgi Tendon Organ’. The Golgi Tendon Organ sends messages to the brain and spinal chord to ensure that contractions are of the desired magnitude. The theory goes that, as the muscle becomes fatigued, or if it is not in a good position to contract, the activity of the spindle is increased and that of the Golgi Tendon is lessened, resulting in uncontrolled contraction—i.e. cramp.



Doing so before and after exercise can help avoid cramps, and stretching is also probably the best way to treat an existing cramp.


Other Causes

Those who study EAMC agree that there are ‘multifactorial’ or several causes involved. One study found that taller, larger triathletes who were currently pushing their pace harder were more likely to cramp. Those who train harder and longer in the days leading up to an event and had higher markers of muscle damage were more prone to cramping. There is also (as with most things) a genetic aspect. If you have a certain variation of one gene in particular—the ‘COL5A1’ gene—you are twice as likely to experience cramps. Poor flexibility and fitness also increase risk.

Avoidance and Treatment of Cramps

There are dozens of proposed ways of avoiding and treating EAMC, the majority of which are not very effective. Even though dehydration and loss of electrolytes are not necessary for cramping to occur, inadequate fluid intake while exerting muscles intensely can lead to cramping much sooner. In one study, when subjects were exposed to conditions of dry heat (37 degrees) and exhaustive exercise designed to cause cramping, those who were given a carbohydrate / electrolyte drink (think Lucozade Sport) experienced the same levels of cramping (actually, slightly more) as when they got no fluid. Those who cramped, did so over twice as soon without the beverage. However; we must be cautious about this study because it is unrealistic that anyone would exercise in such extreme conditions without drinking. Also, these subjects were chosen because they had a history of cramping, so who knows what the results would have been if random subjects were studied. While it is good advice to drink plenty of fluids if you are exercising in the heat and to add carbohydrates and electrolytes if the exercise is going to exceed one hour, this is not so much to avoid cramping as to avoid loss of performance and support general wellbeing.

Stretching seems to be one of the most agreed-upon ways of avoiding EAMC. Doing so before (after warming up of course—never stretch a ‘cold’ muscle) and after exercise helps. It can also be one of the best ways to treat an existing cramp. A slow, easy stretch of the affected muscle will stimulate the Golgi Tendon Organ to re-configure its messages to the brain and the spinal chord and relax the muscle.

Other things that seem to work to some extent or another are: 

1 | Quinine This is the stuff that gives tonic water its distinct taste. Presumably because it is a mild muscle relaxant, it has been shown to decrease the frequency and severity of cramps. However, taking a muscle relaxant before training may decrease performance. You’d also have to drink a very large amount of tonic water or get pure quinine prescribed by a doctor.

2 | Pickle juice Contrary to common opinion, this doesn’t work by increasing sodium levels because sodium/electrolyte levels didn’t change during the resolution of the muscle cramps when it was looked at in the lab. Again, this can be risky because pickle juice is very high in sodium, which could have unpredictable effects on performance and feelings of wellness during exercise.

3 | Pungent/Spicy Drinks One scientist has developed an ‘anti-cramping’ drink containing ginger, cinnamon, and capsicum. This seems to work the same way as pickle juice by stimulating nerves in the mouth and throat, which then numbs nerves in the muscles. There is actually some preliminary research to support this concoction.

4 | Magnesium The research for exercising humans is quite limited, but taking magnesium (for instance, as part of a ZMA product) is a good idea unless your diet includes seven or more daily servings of a variety of fruits and vegetables.


What Doesn’t Work:

1 | Bananas They are high in potassium, but electrolytes don’t specifically help with cramping in normal exercising conditions. Also, the body sweats mostly sodium, tiny amounts of potassium, and other electrolytes—bananas contain virtually no sodium.

2 | DMSO This is the smelly stuff that some people rub on their muscles to try and treat inflammation or to help with the absorption of other topical medicines. For cramping, it is quite unlikely to be useful, since it is only absorbed through the skin and perhaps reaches only a fraction of the muscle.

3 | Calcium Again, electrolytes don’t specifically reduce cramping and if they did, calcium would not be the likely electrolyte to do the job because very little is lost to sweat. Calcium is required for muscle contraction, but the body is more than able to make ample calcium available when needed.

4 | Mustard Theoretically, this should work in a similar way to the pickle and spicy drink, but studies on mustard have failed to show any effect on EAMC.



Contrary to popular belief, cramps are not caused primarily (or at all) by dehydration or electrolyte depletion. Interestingly, it seems the kind of frequent, intense exercise that physique athletes do probably makes them more susceptible to cramping. Most importantly, the best way to avoid cramping is to avoid sudden increases in training load and intensity, stretch often, give yourself periods of off time or take the weight and volume down for a few weeks every few months. Quinine, pickle juice, spicy drink concoctions, and magnesium also may have a moderate beneficial effect. There is no way to totally avoid cramps, but now you have the information and the tools to minimise your risk!


Mark Gilbert is an expert in Sports Nutrition and has worked with elite level athletes and formulated supplements for many of the industry’s biggest companies. See: and the MuscleDiet YouTube channel!