The Effects of Sports Drinks During High-Intensity Exercise on the Carbohydrate Oxidation Rate Among Athletes: A Systematic Review and Meta-Analysis

Abstract

Background: This study examines the effects of sports drinks ingestion during high-intensity exercise for carbohydrate oxidation rate (CHO-O) among athletes.Methods: PubMed, Embase, and the Cochrane library were searched for available papers published up to November 2019. The primary outcome is the carbohydrate oxidation rate (CHO-O), and the secondary outcome is the fat oxidation rate (Fat-O). Statistical heterogeneity among the included studies was evaluated using Cochran's Q test and the I2 index. The random-effects model was used for all analyses, regardless of the I2 index.Results: Five studies are included, with a total of 58 participants (range, 8–14/study). All five studies are randomized crossover trials. Compared to the control beverages, sports drinks have no impact on the CHO-O of athletes [weighted mean difference (WMD) = 0.29; 95% CI, −0.06 to 0.65, P = 0.106; I2 = 97.4%, P < 0.001] and on the Fat-O of athletes (WMD = −0.074; 95% CI, −0.19 to 0.06, P = 0.297; I2 = 97.5%, P < 0.001). Carbohydrate–electrolyte solutions increase CHO-O (WMD = 0.47; 95% CI, 0.08–0.87, P = 0.020; I2 = 97.8%, P < 0.001) but not Fat-O (WMD = −0.14; 95% CI, −0.31 to 0.03, P = 0.103; I2 = 98.2%, P < 0.001). Caffeine has a borderline effect on Fat-O (WMD = 0.05; 95% CI, 0.00–0.10, P = 0.050).Conclusions: Compared with the control beverages, sports drinks show no significant improvement in CHO-O and Fat-O in athletes. Carbohydrate–electrolyte solutions increase CHO-O in athletes but not Fat-O.

Healthy Behavior and Sports Drinks: A Systematic Review

“…Although the review by Coombes [66] indicates that "the use of sports drinks does not provide benefits over water", these drinks are useful to prevent dehydration and heat stroke due to the increase in temperature and sweating rate [62,67]. Especially relevant in intense or prolonged activities, where maintaining adequate hydration [20,21], a correct number of electrolytes [17,18,67], feeling cool [67], and an optimal level of circulating carbohydrates to prevent muscle glycogen depletion and maintain performance are crucial [23,26,31,32]. However, water alone is not sufficient to achieve this in athletes [24,25,72,73].…”

“…In general, it is recommended to limit the consumption of sports drinks and opt for healthier options, such as water, to maintain adequate hydration during physical activity [30]. Sports drinks with optimal levels of carbohydrates and electrolytes (4% to 6%) allow for maintaining adequate levels of hydration and blood glucose, generating less cardiac stress and less fluid loss, improving performance in endurance sports [21,[31][32][33]. In addition, the constant intake of sports drinks during physical activity and exercise may cause intestinal discomfort despite being the most convenient form of intake [34,35].…”

Effects of Grape Syrup Intake on Metabolic Rate and Substrate Oxidation During and After Sprint Intermittent Exercise

“…They are currently available in the market and are publicized to increase the energy level of the individuals consuming them (1). There were numerous claims of commercially available sports drinks about their benefits for substrate oxidation among athletes (2).…”