Effects of Sports Drinks on the performance of Young Soccer Players

This study examined the effects of a sports drink on the performance of young soccer players. Ten competitive young male soccer players, ages 10 and 11, performed two experimental trials while consuming 32 ounces of either a sports drink (G)- Gatorade or a placebo (P)- Crystal Light in a double-blind, crossover design. Both trials consisted of a 15-minute warm-up period, a pre and post exercise test protocol and a 40-minute indoor scrimmage with a five-minute half time. The assigned fluid was consumed just prior to the warm-up, pre-test protocol, scrimmage and post-test protocol as well as during the half time of the scrimmage. The exercise tests included six activities such as shooting velocity, dribbling, passing, jumping, backward running, and sprinting in order to measure skill, agility, power, and speed. The results showed that due to the interaction of the 40-minute scrimmage and the consumption of Gatorade, the post-test shot velocity measurement was significantly (p<0.01) lower for P while G remained similar to the pre-test measurement. Also, there was a significant (p<0.05) decrease in the number of jumps completed for both P and G during the post-test jumping exercise when compared to the pre-test measurement. However, there were no significant difference of treatment, time and/or their interaction for the dribbling, passing, backward running, and sprinting. Many possible reasons may account for this lack of effect. 1) Muscle glycogen may not have been substantially depleted, possibly because the prescribed exercise during the trial was not intense or long enough. 2) Prior to the experimental trials, muscle glycogen stores were sufficient where no additional CHO was necessary (due to the subject's diet on the day of the trial or the short fast prior to the experimental trials). 3) Alternative mechanism, such as increased lactate production or dehydration and not muscle glycogen depletion, may be the cause of impaired skills. 4) A child's increased fat utilization allows for less of a need for manipulation of glycogen stores.