Abstract
This study compared the acceptance of two beverages (5% carbohydrate) of distinct
osmolarities (hypotonic, 180 mOsm/kg and isotonic, 295 mOsm/kg) during the usual training
practice of 97 athletes. A quantitative sensory profile by independent tasters ensured
that organoleptic recognition would be unlikely during the tests. Each drink was consumed
ad libitum during 3 different training sessions, at home. At each Session, a subjective
appreciation of hedonic and post-ingestive physiological effects (6 criteria) was
obtained by means of a questionnaire. At the end of the experiment, the athletes were
asked to express a preference for one of the “six” drinks. More athletes (blindly)
chose the isotonic compared to the hypotonic drink (p = 0.03). This difference was
not due intrinsically to the drinks, which the subjects were unable to distinguish
on any of the criteria, but was related to certain aspects of the consumer's characteristics.
Both groups had different drinking practices: the subjects choosing the isotonic beverage
drank less before (p = 0.001) and more during (p = 0.013) the exercise. Age, sex,
dimensions or type of physical activity (i. e. endurance vs speed/strength disciplines)
were unrelated to the preference, except perhaps the duration of habitual exercise
(p < 0.05). We concluded that athletes, although unable to distinguish a hypotonic
from an isotonic drink, may have specific habits and/or personal characteristics prompting
them to favour one of them.
Key words
Rehydrating beverages - isotonic - hypotonic - osmolarity - ad libitum drinking -
perception - athletes - glucose polymer - training
