The international Society of Sports Nutrition (ISSN) allocates a whole section to getting the electrolyte ‘balance’ right, such is the importance of this in training and exercise. The ISSN’s definition of an electrolyte is ‘a mineral that becomes an ion in solution’ i.e. cellular fluid such as blood, body water etc. So in order for our cells (main components of our organs and muscle) to function as they should, we need to get the balance right! Obtaining/maintaining the ideal distribution between electrolyte and water is affected by one of two things, or both:
1.) Loss of body water
2.) Inadequate replenishment of electrolyte
Which means SWEATING is the area of focus. It is not uncommon for a person undertaking intense physical activity to lose 1 litre an hour, and depending on exercise intensity, this value can increase to more than 3 litres (double the average recommended fluid intake per day)! The consequence of losing excess water is increased electrolyte concentration, meaning there is too much electrolyte compared to water. However, this can also go the other way (although far less common), especially in cooler climates and during less intense exercise where people may actually over hydrate due to reduced sweating, resulting in too much fluid and not enough electrolyte. Either way, the outcome is the same, deranged cellular activities which can negatively impact on physical performance....so what can you do to prevent/limit this.
The term Isotonic drink refers to any beverage that contains fluid, electrolyte (Sodium, Potassium, Calcium, Magnesium, Bicarbonate, Chloride, Phosphate and Sulphate) and 4-8% carbohydrate (4-8g/100ml fluid). The composition of isotonic fluid is electrolyte and carbohydrate, meaning it has the same number of particles in a solution (osmolality) as the body’s water. Through approximately matching the particle concentrations, the absorption of fluid, electrolyte and carbohydrate is markedly increased, but also, the effective replenishment of electrolyte maintains the feeling of thirst which promotes further drinking and better hydration. Despite Isotonic drinks providing carbohydrate (energy source), its purpose isn’t solely for replenishing energy levels; the carbohydrate also balances osmolality (particle concentration) which aids the absorption of electrolyte and fluid further.
Stimulant and Energy Gels
During intense activity, some athletes may opt for stimulant gels that contain Caffeine, Guarana or Taurine to aid focus. This can be taken alongside Maltodextrin based products which serve as a concentrated energy replenishment to support their isotonic beverage. Some products on the market now combine these ingredients providing a potent source of energy and stimulant to support an isotonic beverage.
Inadequate Electrolyte Replenishment
If we get the electrolyte balance wrong, hyponatraemia (low sodium) may occur. Hyponatraemia has been observed during exercise amongst amateur and professional athletes and in this instance is known as ‘Exercise Associated Hyponatraemia (EAH). It occurs due to the excessive consumption of plain fluid, particularly common in cool climates when players or athletes drink high levels of water despite an inhibited urinary response due to exercise (we urinate less when exercising), and reduced sweating due to the cool ambient temperature. This phenomenon is why almost every professional outfit will provide their athlete, player/players with optimally balanced, electrolyte and carbohydrate replenishment (Isotonic) beverages such as Lucozade sport, High 5, SiS Go or a similar isotonic equivalent.
Electrolyte deficiencies do not stop here, and might also include notable reductions in Magnesium and zinc (although not usually linked to sweating) attributed to the elevated metabolic strain of training, and Hypokalemia (low potassium) as a consequence of excessive sweating or over hydration.