I often get athletes turning up feeling fatigued before we even start the session. When I ask them about their hydration status, it usually reveals that they haven’t been drinking enough. More than that, it could be that they need some extra help with their recovery drinks so that they replace the salt and electrolytes lost through their sweating.Sweating is necessary to help your body cool down, but in conditions when the weather is hot and humid, you will be sweating during rest periods, not just during training. Unfortunately losing too much fluid will not only mean that you can’t physically perform as well, but that you can’t think and make decisions as well either.
Relying on thirst as an indicator of when you need to drink more is unreliable as there is a time lag between being dehydrated and then feeling thirsty- it might be too late and you will already have suffered a loss of performance.
The American College of Sports Medicine (ACSM) Guidelines for Hydration around exercise are as follows:
• Hydrate well in the 24hours preceding exercise.
• Drink 400-600ml of fluid 2 hours before training
• Drink 150-350ml of fluid every 15-20 minutes during training
For short duration bouts of exercise, water is a good replacement, but for longer bouts, and if you are training more than once a day, you may have to add something to it. Adding a small amount of salt (half a teaspoon per litre) will not only help the water stay in your body, it will stimulate the thirst mechanism to encourage you to drink more.
Drinking too fast or just drinking plain water will increase the osmosis effect and could lead to extra urination. You will then be losing the fluid as rapidly as you are putting it in. That is one of the problems of using clear urine as an indicator of hydration.
If you use a recovery drink, look for one that has a carbohydrate/protein content in it (be careful of calorie content) as that has been shown not only to help repair and recover the energy loss from exercise, but also helps increase the uptake of fluid into the gut.
Carrying a water bottle to training is one of my “non-negotiables” when training athletes. That and a recovery snack and a training diary. If not, they get extra work at the end.
Tips for remaining hydrated:
• Always carry a water bottle with you throughout the day.• Aim to drink 2 litres of fluid per day as the baseline, and then add what you need for exercise.
• Weigh yourself before and after exercise, look to replace every 0.5kg lost with 750ml of fluid.
• Don’t drink too fast, 500ml every 30 minutes is adequate.
• If training for more than an hour, or doing multiple training sessions, look to have some salt, sugars and protein in your recovery drink or food.