The subject of cramping often creates lengthy debates because so many things can cause or help to prevent them. Most triathletes take the sport seriously and will usually have a varied and healthy diet. That said you can’t always rule out nutrition issues because some might be lacking in certain vitamins and minerals. If in doubt contact a nutritionist. Don’t just start randomly adding supplements to your diet. It is possible to sweat in the pool so hydration is not to be ignored, and like Grainger and Mitchell from Team Sky found with cycling, conditioning and biomechanics are key in the water.
Cooler temperatures can bring the cramping problem on quicker because a cold muscle is harder to keep relaxed. If you suffer cramps in the cold it might be worth starting open water swimming later in the season as temperatures rise. It is also worth looking at the design of wetsuit you have. Some have flexible textile panels for quick removal, which means they’re not as warm as those with full neoprene. This makes it easier for cold water to pass rather than warming up the water sealed inside.
There is no one best way to avoid cramps. Taking care of as many factors as possible will help to eliminate them. Beyond diet, hydration and stretching there is no substitute for good positioning and consistency in the water because of the unfamiliar legs and feet are put in. The more time you spend in this position the more you will relax in it. It’s also worth throwing in a few gentle stretches between sets and be kind to your body when you push off from the wall.