At the beginning of each year the pavements suddenly become much busier, with people of all ages and abilities pounding the streets in preparation for the many running, duathlon and triathlon events over the next few months. A common sight amongst these runners is a bottle of lucozade, gatorade, powerade or other carbohydrate drinks, as recommended by trainers and nutritionists worldwide.
But when was it discovered that carbohydrate consumption and supplementation led to an increase in performance?
The first study to suggest performance could be increased due to carbohydrate intake was conducted by a group of American researchers between 1923 and 1924. They began by measuring the blood glucose levels of runners after they had completed the Boston marathon in 1923. It was shown that the glucose concentrations were markedly lower, and from this it was hypothesised that low blood glucose levels are a cause of fatigue.
The following year several participants for the Boston marathon were asked to consume carbohydrates during the race. Obviously this was before lucozade and energy gels were invented, so the runners were asked to eat candy whilst running. They were also asked to eat a high carbohydrate diet in the lead up to the race. All the runners improved their times from the previous year and had a much higher blood glucose level.
In the 1930’s another study was conducted into the use of carbohydrates to improve endurance performance, however, this study used dogs rather than people. Two dogs were made to run without being fed any carbohydrates. It was noted that the dogs became hypoglycemic (low blood glucose) and fatigued after 4-6 hours. The test was then repeated but the dogs were fed carbohydrates during the exercise and the dogs ran for between 17 and 23 hours.
Although neither of these studies would be seen as being scientifically relevant now, they were two of the first to look into dietary supplementation to increase performance. Hundreds of studies are conducted every year with millions being spent to ensure athletes of all abilities can perform at their peak, however, the significance of these early studies cannot be overlooked.
