Nutrition: How Close to Competition Can Carbohydrate Drinks be Taken and Still be Effective?

Dick Moss, Editor, PE Update.com

    It has been well documented that the ingestion of carbohydrate drinks such as Gatorade and Powerade improves athletes' endurance in athletic events lasting over an hour.
    Past research has shown performance benefits when such drinks were ingested at several different pre-competition times: 60 minutes before exercise; 45 minutes before exercise; 20 minutes before exercise; and immediately before and during exercise.
    A new study, performed at the University of Ulster, examines carbohydrate ingestion 15 minutes before exercise (but not during). It's of interest to those athletes who can take a quick drink immediately before the start of competition but will not have that opportunity once the competition begins. Such athletes might think, “Will sipping some Gatorade just before the game really help me? Will it actually get into my system? Why not just drink water?”
    In fact, drinking the carbo drink will help.
The Study
     The endurance of test subjects was compared after drinking, 15 minutes before exercise, one of the following
1. Powerade
2. A flavoured water placebo
3. Nothing at all.
    Subjects drank 8 ml. per kilogram of body weight and no liquids were ingested during the exercise session itself.
    The exercise session simulated the stop-and-start nature of many team sports. It included a total of one hour of exercise, consisting of 4 x 15 minute blocks of 90-second segments of shuttle-walking and running. The segments included 3 x 20 m walking, 1 x 20 m maximum-speed sprint, 3 x 20 m jogging, and 3 x 20 m fast running. After the final block, subjects performed a shuttle run to exhaustion. It was this final run to exhaustion that was measured and compared.
Results
    The subjects who ingested the carbohydrate solution ran 47 seconds longer than the placebo group and 56 seconds longer than the group that ingested no fluids whatsoever. This was considered a significant difference.
    Researchers believe that ingesting a drink such as Powerade or Gatorade increases carbohydrate stores in the muscles, which delays the onset of fatigue.
Conclusion
     This study adds another proven pre-exercise nutrition option for athletes wanting to improve performance in events lasting over an hour. Carbohydrate drinks such as Gatorade or Powerade can be ingested at any of the following times and still be
effective in delaying fatigue:

• 60 minutes before exercise
• 45 minutes before exercise
• 20 minutes before exercise
• 15 minutes before exercise
• Immediately before and during exercise

Reference: G. W. Davison, C. McClean, J. Brown, S.. Madigan, D. Gamble, T. Trinick, E.. Duly, “Effects of Ingesting a Carbohydrate-Electrolyte Beverage 15 Minutes Prior to High-Intensity Exercise Performance.” Research in Sports Medicine, 16: 155-166, 2008.

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