drinking. If, however, a second bout of exercise is
to be undertaken and a decrement in perfor-
mance is to be avoided, the water lost must be
replaced as completely as possible before the
exercise commences and further sweat produc-
tion occurs.
Prioritizing rehydration and recovery
after exercise: carbohydrate vs.
water replacement
Drinks consumed during or after exercise are
generally intended to replace the water and elec-
trolyte losses incurred as a result of sweat secre-
tion, and also to provide carbohydrate to
supplement or replenish the glycogen stores in
the liver and the working muscles. The relative
importance of providing water or substrate is
influenced by many factors. However, distur-
bances in body fluid balance and temperature
not only can impair exercise performance but are
potentially life-threatening (Åstrand & Rodahl
1986). In comparison, the depletion of carbohy-
drate stores in the liver and working muscles will
result in fatigue and a reduction in exercise inten-
sity, but on the whole presents no great risk to
health. Therefore, except in situations where
depletion of body water has not occurred, the
first aim of postexercise recovery should be to
restore any fluid deficit incurred, followed by
repletion of liver and muscle glycogen stores.
It must, of course, be recognized that these
aims need not be mutually exclusive. Selection of
suitable food and drinks should provide both
the carbohydrate necessary for optimization of
muscle and liver glycogen resynthesis and the
water and electrolytes necessary for replacement
of sweat losses and restoration of fluid balance.
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