Sport & Exercise Hydration
Updated: Jan 22
We know that during exercise and sport we lose a lot of fluid through sweat.
Preventing dehydration is just as important as staying hydrated so minimise the intake of dehydrating drinks in the lead up to exercise:
Carbonated drinks, incl. diet drinks
Tea (black and green)
The timing of fluid intake is important pre, during and post exercise. It can take the body, for example, up to six hours to fully hydrate after 90 minutes of vigorous exercise; yet for most of us, we may not continually intake fluids for that period, especially if we exercise in the evening.
At a minimum I recommend increasing hydration at least four hours before exercise, taking in about 200mL (approx. one glass) of water every 20-30 minutes. Cease about 20-30 minutes before exercise (as you need to give time for your stomach to empty).
During exercise take small sips of drink, frequently. Avoid large mouthfuls as you may swallow air and upset the stomach.
Rates of hydrations will vary between individuals but as general guideline I recommend at least 750mL (25 fl oz) per hour when exercising at about 75% of your max effort and at least 1L (34 fl oz) per hour when over 75% max effort. The longer the exercise period, a larger volume of fluid will be needed each hour to maintain optimal hydration.
Post exercise hydration should commence immediately after exercising. Keeping fluids up will aid in the flushing of toxins and reduce acidity levels. I recommend at least the same volume of fluid taken during exercise, should be taken in the first hour post exercise. Decrease that volume gradually as comfortable for the next few hours.
I use water as my pre and post exercise hydration. Some literature suggests including some fructose and sugars post exercise and that is fine. I typically eat a piece of fruit post weight-training but stick to water post cardio training; just personal preference and it works for me.
I drink a “sports” drink during exercise as it can increase the body’s ability to take up fluid and also be a source of energy and aid recovery. Here are some key sport’s drink tips:
Fruit juices can cause gastric distress. Juice content should be approx. 5% of total volume and avoid acidic juices like apple (opt for a fruit juice blend or a less acidic juice like pear juice). The fructose (a type of sugar) in the juice will help replenish glycogen levels (a source of energy stored in your body).
A polymerised glucose (e.g. maltodextrin) can aid gastric emptying and provide the body with a quick source of easily digestible carbohydrate to boost energy. Aim for 6-8% concentration.
Magnesium, potassium and sodium will aid many essential bodily functions such as muscle contraction, nerve impulses and also help prevent cramping/muscle soreness.
I make my own sports drink as I get to choose what goes in it and it is also less expensive. Here is a suggested recipe for a 750mL drink bottle (25 fl oz):
Approx. 60mL (2 fl oz) 100% fruit juice (non-diet and no added sugar)
Approx. 100 mL (3.4 fl oz) coconut water (source of magnesium, potassium, sodium)
Half the juice of a fresh lemon (alkalising effect to the body)
45g maltodextrin (6% concentration) - optional (also pretty flavourless)
Top up with cold water and ice