After a year away from the sporting pitches and with the possible return to full training of Semi Professional and Amateur (Grass roots) sports in June, we must never forget the fundamental role that water plays in our body, cooling, nutrient transport, joint lubrication, digestion, and absorption.
The Human body is 60 or 70% made up of water, many of it is found in the blood and muscles. The amount of water in the body is limited, if the losses are not replaced there may be a decrease in heat transmission from the muscles to the skin, the consequence of which will be the increase in body temperature, favouring the risk of dehydration, the first signs are intense thirst, dry body, hot, dry skin and mucous membranes, cramps (sodium is lost due to perspiration), depletion by hydro-electrolytic imbalance (which manifests with dizziness, sweat, tachycardia, headache, paleness, etc.), heatstroke (decreased level of consciousness, neuromuscular un-coordination).
Dehydration causes a decrease in aerobic capacity, maximum aerobic potency, muscle endurance and the ability to develop physical work. In addition to the physical qualities mentioned, mental faculties, fine coordination and therefore it is essential to provide fluids during exercise, mainly when large water losses occur. The proper way to hydrate will depend on:
- The goal to achieve (increase muscle mass, decrease adipose tissue, optimize performance, etc.)
- The intensity, frequency, duration, etc. of the training to be performed
- The weather (temperature and humidity)
- Individual variations (there are people who sweat more than others) Having these factors present should opt for the right drink (water and / or sports drink) and rehydration strategies should be practiced during training. Recommendation: Never try a new strategy on match day, that is what training is for.
The goal is to ensure a state of euhydration (i.e. normal hydration) and prevent gastrointestinal discomfort. Avoid diuretic or gas drinks (alcohol, coffee, etc) and Drink between 300-600ml of water (without gas) in the pre-match time (preheating); and more if the temperature and/or humidity are high or if you are a “profuse sweater”.
Normal hydration status is defined the presumed condition of healthy individuals who maintain water balance. Evaluation of hydration status is not easy, as during daily activities or exercise, fluid compartments are constantly fluctuating and therefore the evaluation of a single body fluid compartment volume is insufficient to provide valid information about total body water (TBW) .
HYDRATION DURING (Matches/Training)
Players need to be educated regarding the benefits of fluid replacement to promote performance and safety and the potential risks of both hypohydration and hyperhydration on health and physical performance. Quantify sweat rates for physically active individuals during exercise in various environments. Work with individuals to develop fluid-replacement practices that promote sufficient but not excessive hydration before, during, and after physical activity.
The goal is to replenish sweat-lost water and provide an energy source, to delay glycogenic emptying and therefore fatigue.
With high-performance athletes, restricting dehydration to no more than 2% body mass loss helps to maintain the physiological, perceptual, and safety aspects of their exercise while aiding in exercise recovery and subsequent training sessions.
Dehydration is the process of water loss from the body and being in a dehydrated state means you no longer have sufficient fluid in your body to optimally function. Naturally, even at rest we lose fluid by as much as 1-3L per day.
In any training greater than 60 minutes long and high intensity, Water and/or sports drink, if possible, containing the necessary and sufficient nutrients such as sodium (to promote water absorption) and carbohydrates. The latter delay, but do not prevent, muscle fatigue; since the utilization rate is higher than the ability to eat carbohydrates during exercise.
Always have drinks during a pause in a game such as penalties, conversions, at half-time and, always when the referee allows you to… or between exercise sessions in the gym/field. Pay special attention to those who remain substitutes, they must rehydrate in the substitutes’ bench, to be prepared in case they have to enter the game.
If we are dehydrated our performance will NOT be optimal, with weight loss of 2% there is decreased athletic performance, 3% decrease in physical endurance 4% there is decreased muscle strength, thus having a personal plan and drinking a sufficient amount of fluid could be the difference between winning and losing.
You should not wait to be thirsty to drink liquid; at that moment you are already dehydrated!!
Other reasons for inadequate liquid intakes are lack of availability of liquids, unrespecting liquids, sports tradition, lack of awareness in the subject.
The volume of liquid lost depends on the intensity and duration of the activity, the temperature and ambient humidity, the clothing used, the acclimatization of the person to heat, the movement of air and solar radiation. The thirst mechanism is activated when a lot of fluid has already been lost, so it is important to control losses by comparing pre- and post-activity weight and urine color (the more yellow, the greater fluid loss, usually).
Example of how urine colour might vary with Hydration status:
The strategy to follow is: drink 1/2 litre of sports drink as soon as you finish training/playing and then you should consume up to 150% of the lost weight, within 2-3 hours. Example: 90Kg player with a dehydration of 2% lost 1.8Kg, the volume to consume would be 2.7 litres (2700ml): 1st half litre and then 2200ml.
As a rule, consume between 500-1000ml/hour of sports drink or mineral water (without gas), larger amounts may be necessary on days of high temperatures.
Although there is no exact answer for how much water you should consume as everyone may have different needs depending on individual and environmental factors, aim for approximately 35ml of fluid per kg body weight. That is just over 2 litres for a 60kg adult, or 2.8 litres for an 80kg adult. Active children should aim for 1-1.5 litres per day (approx. 4-6 glasses) and everyone should consume extra fluid if exercising.
All this is plannable and trainable!! Do not leave hydration released at random. Do not test these strategies for the first time in a match; but try to get used to drinking workouts every 15-20 minutes.
DEHYDRATION is one of the main 5 nutritional factors related to fatigue and decreased performance, along with the emptying of glycogen deposits (energy) in active muscles, decreased blood glucose (hypoglycemia), gastrointestinal discomfort, excess adipose mass (ballast). All is preventable with food education and “training” habits.
It is up to you to be hydrated.
1-2 hours before exercise – suitable foods include:
- Milk shake or smoothie
- Breakfast cereal with milk
- Cereal bars
- Fruit-flavoured yoghurt
Less than 1 hour before exercise – suitable foods include:
- Sports drinks
- Squash drinks
- Jelly sweets
Maintaining Euhydration Preserves Cognitive Performance, But Is Not Superior to Hypohydration Stephen P. J. Goodman, Ashleigh T. Moreland & Frank E. Marino Journal of Cognitive Enhancement volume 3, pages338–348(2019)
Eat Well, Feel Well: The Importance Of Hydration: https://www.irishrugby.ie/2020/05/12/eat-well-feel-well-the-importance-of-hydration/
National Athletic Trainers’ Association Position Statement: Fluid Replacement for the Physically Active J Athl Train. 2017 Sep; 52(9): 877–895.
Key tips on hydration Educational tool-measuring hydration status – European Hydration Institute