When a muscle contracts involuntarily and stays contracted, you end up with what’s commonly known as a muscle cramp. If you’ve ever had to stop exercising because of a muscle cramp, you know how painful these can be.
The top sights for muscle cramps are the calf, hamstrings, thigh (quadriceps), feet, hands and arms. Four of the main causes of exercise related cramps include:
- The nerves that stimulate muscle become overstimulated
- Muscle fatigue
- Dehydration
- Electrolyte imbalance
So how can you prevent cramping? First, warm up, stay warm (versus sitting in between bouts of physical activity, keep moving) and stretch after exercise. Try PNF stretching or yoga to achieve new levels of flexibility. Next, make sure you are trained for what you are doing – progressively increasing your workload by about 10% per week will decrease the likelihood of fatigue during exercise.
How much should you drink to stay hydrated? This varies tremendously between athletes based on sweat rate, heat acclimatization, body weight, clothing (more gear and more clothing = more fluid losses through sweat), age (older athletes and young kids are more likely to become dehydrated), conditioning level, heat, humidity and sport. General recommendations include:
- 4 hours before exercise – consume 5-7 ml per kg body weight (13 – 17 fluid oz for a 160 lb person)
- 2 hours prior to exercise – consume more fluid, especially if urine is dark in color and scant
- Drink while exercising – about 3-8 oz of a sports drink every 10 – 20 minutes if exercising over 60-90 minutes (exercising intensely).
For those individuals walking or exercising lightly and aiming for weight loss versus performance, choose a zero calorie sports drink that contains electrolytes. That way, you’ll get the electrolytes you need to prevent hyponatremia and cramping without hampering your weight loss goals.
Also – weigh yourself before and after exercise. For every pound of sweat you lose, you should drink about 16 – 24 oz of fluid.
What about electrolytes? We lose the electrolytes sodium, chloride, potassium, calcium and magnesium in that order. So it makes sense to replace them in that order – i.e. choose a drink that contains mainly sodium chloride as well as a little potassium and calcium (and possibly magnesium). Sports drinks generally have enough sodium for most athletes. However, some athletes are salty sweaters – you can see crystals of salt on their ears and face while they are exercising (or dogs happily run up and lick the salt off their legs when they are finished running). These athletes likely need more sodium and can get it by adding a product like SaltStick to their drinks (I recommend consulting with a sports nutritionist to add the right amount of sodium since the range is about 460-1150 mg per liter of fluid).
