Water is essential to all life forms, and for dancers is a vital performance enhancing component. Water accounts for between 40 and 70% of our body mass (McArdle et al., 2015), with 60-65% of this water contained within cells (intracellular), the remainder outside (extracellular) (Koutedakis & Craig Sharp, 1999). In terms of body composition, of which we are all very individual, water accounts for approximately 65-75% of the weight of muscle tissue but only about 10% of the weight of fat (McArdle et al., 2015). It follows that two individuals might weigh the same but owing to different body compositions will have differing total body water percentages.
Fluid requirements differ from dancer to dancer according to different factors that might include amongst others your body size, your genetics, your current level of fitness and the intensity and duration of the exercise performed. Mastin & One Dance UK (n.d.), advise that ‘it is very difficult to recommend a general fluid requirement that meets the needs of all dancers’, and advise that the best way to estimate fluid requirements is to weigh oneself before and after exercise, with each kilogram of weight loss accounting for approximately 1.2-1.5 litres of fluid, remembering to account for any fluids consumed during the session.
During exercise the muscles produce heat as a by-product, in fact 75% of the energy we put into dance is converted into heat (Koutedakis & Craig Sharp, 1999). This heat has to be dissipated in order to maintain the body temperature with safe limits and avoid overheating. Water is carried from the hot muscles to the skin’s surface via the capillaries where it evaporates as sweat. The amount of water in the body is balanced by very delicate systems, and all water losses need to be replaced by an equivalent water intake. Water is not only required to cool the body via sweat production, it is required by the body to transport nutrients around the body. It is also essential for the maintenance of adequate blood volume and essential for the optimal functioning of the heart. Water is an excellent source of certain minerals. Electrolytes are minerals that facilitate the neural impulses that control muscle activity (amongst other vital intracellular metabolic activities). When the body sweats excessively it loses electrolytes through sweat production and this impairs one’s maximal physical performance. This is mainly due to decreases in plasma volume which affects the body’s ability to utilize carbohydrates.
If fluid losses are not adequately replaced the dancer can become dehydrated and this can lead to electrolyte deficits and dancers are likely to experience muscle cramps and muscle fatigue. Mastin, on behalf of One Dance UK (n.d.) suggests that greater levels of dehydration affect the dancers’ strength, their ability to concentrate, and increases the potential for injury. An easy way to recognise dehydration is the pee test, with darker, lesser quantities of urine indicating dehydration. Koutedakis & Craig Sharp (1999) suggest that a 2% loss of fluid in terms of body weight reduces one’s capacity for maximal exercise by 15%; at 5% this capacity decreases by an astonishing 30%, and 9-12% has the potential to be fatal.
Should dancers only drink water? Should they consider sports drinks and fluid replacement drinks? Fluid replacement drinks often contain electrolytes such as sodium as well as carbohydrates. This content assists in replacing fluids quicker than plain water. Energy drinks often contain greater amounts of carbohydrates in order to boost energy losses. Such drinks are often classified as hypotonic (low osmolality), isotonic (normal osmolality), or hypertonic (high osmolality). If we consider the first one; a hypotonic drink, as the name suggests, will contain fewer electrolyte and carbohydrate particles than the body’s own fluids, and will therefore be absorbed by the body faster than plain water. This would therefore be beneficial in hot environments. Isotonic drinks contain the same amounts of electrolytes and carbohydrates as the body and will therefore be absorbed as fast as plain water, which is appropriate for exercise in normal temperatures. Hypertonic drinks contain more electrolytes and carbohydrates than the bodies fluids and will therefore be absorbed slower than plain water and could therefore be consumed post-workout in order to supplement losses of carbohydrates etc. In a factsheet for dancers, Mastin & One Dance UK suggest drinking plain water for low to moderate levels of intensity of less than an hour’s duration; for moderate to high level intensity, lasting less than an hour, they suggest either water or a hypotonic drink; and for high intensity activity lasting longer than an hour they suggest a hypotonic or isotonic drink.
So, always try to begin your class/performance in a hydrated state. Drinking small amounts frequently rather than a large amount in one go is likely to be preferable to avoid bloating. Getting into the habit of carrying a water bottle with you for this purpose becomes part of good practice. Don’t rely on your thirst as an indicator of the need to replace fluids for at this stage it is likely you are already dehydrated; and be aware that some drinks, such as tea and coffee, may actually have a dehydrating effect. If you do experience muscle cramps Mastin & One Dance UK (n.d.) suggest a consuming a hypotonic or isotonic drink rather than plain water.
References:
Koutedakis, Y., & Sharp, N. C. Craig Sharp. (1999). The fit and healthy dancer. Wiley.
Mastin, Z. & One Dance UK. (n.d.). 15: Fluid for dancers. https://www.onedanceuk.org/wp-content/uploads/2017/11/DUK-Info-Sheet-15-Fluid-for-dancers.pdf
McArdle, W. D., Katch, F. I., & Katch, V. L. (2015). Exercise physiology: Nutrition, energy, and human performance. Wolters Kluwer.