It’s a runner’s worst nightmare—you’re running the last mile of a marathon you’ve spent months training for and you’re stuck with a debilitating leg cramp. For readers unaware of what a charley horse is, it’s the name for a leg cramp that is severely painful. One moment you’re flying, the next you’re hobbled, in agony. For years we pointed fingers at dehydration or electrolyte loss as the culprits. But neither cause holds up to close examination. Studies on ultra-distance runners and triathletes indicate that neither hydration nor electrolyte status is directly associated with cramping—even if you seem to cramp more on hot days. Conventional wisdom fails again.It’s easy to wonder: why charley horses occur in the first place, how you can avoid them and what you’re supposed to do when you’re experiencing one. Here’s a complete guide to preventing (and treating) this painful nuisance.
What causes charley horses?
The causes of charley horses can stem from a variety of medical issues, ranging from a simple lack of proper nutrition to nerve compression in the spine. The most common causes include the following:
- Rigorous physical activity in hot temperatures
- Inadequate blood flow or poor circulation
- Overexertion during exercise
- Not stretching properly or enough
- Deficiency in magnesium or potassium
- Muscle injuries
- Spinal cord injury or pinched nerves
In the case of exercise-induced muscle cramps, there are still a lot of questions to answer, but an emerging picture is this: Cramps are probably the result of altered neuromuscular control. Altered neuromuscular control comes from fatigue in working muscles. One source of fatigue is faster-than-normal pacing (more evidence here, and here.) One study says, “Evidence suggests that runners are placing greater demands on their muscles during the race relative to their current state of training.”
Muscle damage, possibly from incomplete pre-race tapering (more evidence here), and prior injury (more evidence here) to the cramping muscles also contribute to fatigue and cramps. Other contributing factors include chronic illness, family history, and certain medications.
How can you prevent charley horses?
Most causes, save for pinched-nerve issues, are fixable with minor lifestyle and diet changes. Being mindful Stretching, staying hydrated and drinking beverages with electrolytes in them are all going to become your go-to measures for preventing charley horses.
Running happens through groups of muscles working in coordination. Uphill running demands work from the glutes, quads, hamstrings, adductors, and calves. Downhill running requires shock absorption from the quadriceps, hamstrings, and adductors as well as the connective tissue of the knees, hips, back, and feet. Hip abductors, feet, and lower legs work constantly in all phases of running, both in propulsion and shock absorption. If one muscle can’t contribute adequately then it means another muscle or muscles must work harder, thus risking cramps.
If you’ve ever tried executing a complex task requiring precise movement when you’re exhausted, you understand altered neuromuscular control. You’re stiff and clumsy. Altered neuromuscular control happens at both a conscious and unconscious level.
Successful running requires variable amounts of precisely regulated tension; think of a light controlled by a dimmer switch. Running rarely requires either full contraction or full relaxation of the working muscles. The ability to modulate muscular contractions diminishes with fatigue. A cramp happens as a result of the neural dimmer switch getting stuck in the “on” position as a consequence of fatigue.
Specific training is the first line of defense against cramps. Training specifically means regularly running on terrain similar to your race. Preparing for the Boston Marathon is a good example. Boston’s infamous Newton Hills sit between miles 17 and 21. Here, runners must climb and descend multiple times while fatigued—not only by the previous miles, but also by significant downhills during those miles. Thus, training should include hill runs at the end of long runs and careful downhill running to build specific strength while avoiding injury.
That goes for your running surface, as well: sand, pavement, snow, gravel, sloped roads, et cetera. All of these surfaces place unique demands on your muscles. Train appropriately for the specific demands of your race or where you run most often.
As far as nutrition goes, inadequate fueling while you’re running leads to early fatigue independent of any hydration or electrolyte concerns. Adequate fueling fights fatigue and may reduce cramping. Try consuming the fuel of your choice earlier and more frequently than usual while you’re running. Start conservatively to avoid GI distress.
And take care to ensure your body receives enough magnesium, potassium and calcium. Don’t forget to stay hydrated throughout the day and drink electrolytes when necessary (especially if you have experienced a charley horse recently).
How can you treat a charley horse?
The best way to stop charley horses is to avoid them. However, there are a couple of ways to fight muscle cramps if, and when, they strike.
Stretching is effective at temporarily calming the angry muscle. You probably already do it when you get a cramp. Contract the opposite muscle to make the stretch more effective. For example, contract your quads while stretching a cramped hamstring.
Here are a handful of other effective stretches to use in the moment:
- Position your weight on the leg that’s cramping and bend your knee slightly.
- While sitting down, hold both ends of a towel with your hands and place the middle of the towel under your foot. Lift your leg carefully with the towel until you feel the cramping muscle stretch.
- Step into a lunge with the leg that isn’t cramping. This will stretch the leg muscles that are contracting.
- If the cramp is in the quad, lean on a wall or a chair and pull your foot up towards your buttocks until you feel the cramp start to subside.
While research is limited, pickle juice shows promise for curing muscle cramps. Mustard may have the same effect. The vinegar in both substances is probably the key. The process isn’t fully understood, but the idea is that the vinegar stimulates certain receptors in the mouth that trigger a neurological reset of cramping muscles. Weird? Yes, but there is significant anecdotal evidence that it works.
But rather than focus on race-day cures the best ways to avoid cramps are specific training, strength training, and adequate tapering, plus proper pacing and fueling.
Strengthening cramp-prone muscles can also help them resist cramping over time. Strengthening supporting muscles will also help reduce the workload of cramp-prone muscles. An expert tip: Do a strength training session directly after a hard run to simulate conditions under which cramping occurs.
To let something as easily treated as charley horses stand in the way of our passion for athletics is obviously not an option. As runners, being able to effectively use our bodies is a fundamental part of who we are. Luckily, adequate stretching, watching your diet and avoiding overexertion is what will keep us running safely and happily every day of the week.