Consuming potato puree is as good as commercial carbohydrate gels in boosting the performance of trained athletes, according to a study which may help expand the flavour choices available among energy boosting food.The researchers, including those from the University of Illinois in the US, said that potatoes are a promising alternative for athletes as they are cost-effective, nutrient-dense, and a whole-food source of carbohydrates.
The study, published in the Journal of Applied Physiology, noted that potatoes can serve as a savoury fuel option for athletes participating in races, compared to the high sweetness of carbohydrate gels.
"Our study aim was to expand and diversify race-fuelling options for athletes and offset flavour fatigue," said co-author Nicholas Burd of the University of Illinois.
As part of the study, the researchers recruited 12 healthy participants who rode an average of 267 kilometers every week on their bicycles, with several years of training under their belt. The cyclists had to reach a specific threshold for aerobic fitness, and complete a 120-minute cycling challenge followed by a time trial in order to qualify as participants in the study.
The selected cyclists were then randomly assigned to one of three conditions during the experiments where they either consumed water alone, a commercially available carbohydrate gel, or an equivalent amount of carbohydrates from potatoes. The research team standardised the food consumed by the 12 cyclists for 24 hours before repeating the 120-minute cycling challenge and time trial that was designed to mirror typical race conditions.
The researchers measured the cyclists' blood glucose levels, core body temperature, exercise intensity, gastric emptying, and gastrointestinal symptoms. They also measured concentrations of lactate -- a metabolic marker of intense exercise -- in the blood of the participants.
"We found no differences between the performance of cyclists who got their carbohydrates by ingesting potatoes, or gels at recommended amounts of about 60 grams per hour during the experiments," Burd said.
According to Burd, both groups saw a significant boost in performance which was not seen in those consuming only water. The study noted that plasma glucose concentrations went up by a similar amount in those consuming potatoes and gels. The heart rates of the cyclists who consumed potatoes and gels also increased by a similar amount over those who only had water, and they were speedier on the time trial, the researchers said.
However, the study noted that the cyclists who consumed potatoes experienced significantly more gastrointestinal bloating, pain, and flatulence than the other groups. This may be due to the larger volume of potatoes needed to match the glucose provided by the gels, Burd said. The average gastrointestinal symptoms were lower than previous studies, indicating that both carbohydrate conditions were well-tolerated by the majority of the participants, the study noted.
"All in all, our study is a proof-of-concept showing that athletes may use whole-food sources of carbohydrates as an alternative to commercial products to diversify race-fuelling menus," Burd said.