Cramping is a concern for a lot of athletes and unfortunately, there is no clear reason or answer for cramping. Although most athletes think that electrolytes, sodium and water are the trick to prevent cramps, I believe the daily diet has a lot to do with cramping. Most athletes complain of cramping from a hot race or during an intense workout/race. In the second case, anytime you push your body at a high intensity, you are relying on your muscles to relax after contracting. For this to happen, there must be a steady influx of electrolytes into the muscles in order to contract and relax and those electrolytes are more than sodium and potassium. There are many electrolytes needed in the body and those vitamins and minerals are found in the foods we eat. That is, if you consume wholesome and natural food rather than a diet high in processed food. When it comes to the diet of athletes, eating food is more than looking slim, toned or lean. Every food that you put in your body has a purpose. Donuts serve no purpose. Pizza, well it depends on how healthy or unhealthy you make the pizza. Fruits, veggies, complex carbs, healthy fats, low fat/lean protein, water...YES YES YES...GOOD for your body!!
Rather than waiting until a race to provide your body with healthy nutrients eat those healthy foods on a daily basis. And, if you are prone to cramping, make sure you aren't "water and sodium loading" on the days leading up to a race. Drink water all the time and take a sport product that provides all types of electrolytes.
Cramping is an individual issue and sometimes it comes down to reducing intensity to alleviate cramping. When it comes to racing and training in the heat, be sure you are consuming calories and fluids at a steady intake and make sure you aren't overhydrating or drinking concentrated drinks. 1000 calorie bottles...yikes! Give your body around 180-240 calories for the 3+ hour workouts and be sure to consume around 20-24 ounces per hour. If you are taking in too many calories at one time (or too many calories per hour) your stomach never allows the undigested calories to get to your blood stream to go to your working muscles.
A few more thoughts for the people who don't drink enough water...
As far as cramping goes, many athletes think that the diet is lacking in salt. First off, you need to see if you are drinking enough water. Dehydration (even if you don't feel thirsty) is a big cause of cramping. Researchers aren't sure if it is salt, electrolytes or not enough water that cause cramping but I'd first look at your water intake. I recommend 1 bottle of water (around 16-24 ounces) between meals and at least 1 cup (8-10 ounces) with your meals. Also a bottle of water for 60 min or less workouts and for workouts more than an hour, 1 scoop Heed w/ water in a sport bottle. Workouts over 90 min. in the heat, 1 scoop HEED w/ endurolyte powder, endurolyte capsules (1-2 per hour) or liquid endurance.
Remember, you can get your electrolyte level higher by including a wide range of fruits and veggies in the diet. Bananas are great, especially in a smoothie or oatmeal but also make sure you are adding veggies to your meals and snacks and eating plenty of fruit during the day. Bananas aren't the only food with potassium and potassium isn't the only electrolyte you need with sodium.
Healthy options of sodium-rich foods are canned food (give a rinse before using) such as fruit, beans, veggies, soup, etc. Also, cottage cheese, some lean meat and cheese are high in sodium. Find healthy ways to add salt to the diet and avoid adding salt from the salt shaker.
My last reminder is to make sure that you give yourself a good warm-up, especially for long or intense workouts. Pushing too hard, too fast can cause cramping and giving yourself ample recovery during intervals can help muscles relax.
For races, I recommend Hammer endurolytes: take 1 a day on the 3rd day before the race and take 2 a day on the two days before a race. On race day morning take 2 pills and drink water and your primary maltodextrin rich sport drink on race day morning before the race.