The Effect of Carbohydrate Ingestion on Performance during a Simulated Soccer Match

Julia Goedecke,Hafsa Mahomed,Michael Lambert,Waheed Chicktay,Justin Durandt,Nicholas White

doi:10.3390/nu5125193

Abstract

Aim: This study investigated how performance was affected after soccer players, in a postprandial state, ingested a 7% carbohydrate (CHO) solution compared to a placebo (0% CHO) during a simulated soccer match. Methods: Using a double-blind placebo-controlled design, 22 trained male league soccer players (age: 24 ± 7 years, wt: 73.4 ± 12.0 kg, VO2max: 51.8 ± 4.3 mL O2/kg/min) completed two trials, separated by 7 days, during which they ingested, in random order, 700 mL of either a 7% CHO or placebo drink during a simulated soccer match. Ratings of perceived exertion (RPE), agility, timed and run to fatigue were measured during the trials. Results: Change in agility times was not altered by CHO vs. placebo ingestion (0.57 ± 1.48 vs. 0.66 ± 1.00, p = 0.81). Timed runs to fatigue were 381 ± 267 s vs. 294 ± 159 s for the CHO and placebo drinks, respectively (p = 0.11). Body mass modified the relationship between time to fatigue and drink ingestion (p = 0.02 for drink × body mass), such that lower body mass was associated with increased time to fatigue when the players ingested CHO, but not placebo. RPE values for the final stage of the simulated soccer match were 8.5 ± 1.7 and 8.6 ± 1.5 for the CHO and placebo drinks respectively (p = 0.87). Conclusions: The group data showed that the 7% CHO solution (49 g CHO) did not significantly improve performance during a simulated soccer match in league soccer players who had normal pre-match nutrition. However, when adjusting for body mass, increasing CHO intake was associated with improved time to fatigue during the simulated soccer match.

Highlights

Soccer is defined as an intermittent sport characterised by periods of high-intensity play in addition to periods of sub-maximal effort over ±90 min
The players in most of these studies ingested 5 mL/kg of a 6%–7% CHO solution prior to exercise, and 2 mL/kg every 15 min during exercise [7]. These studies have found that CHO ingestion before and during exercise reduces muscle glycogen utilization [10,11], maintains plasma glucose levels [12], improves running time to fatigue [13,14,15] and coordination [12,14] in the latter stages of the exercise trial
When exploring whether differences in body mass of the players influenced the performance outcomes, we found that body mass modified the relationship between time to fatigue and drink ingestion (p = 0.023 for drink × body weight interaction), such that lower body weight was associated with increased time to fatigue when the players ingested CHO (r = −0.66, 95% CI: −0.85 to 0.33, p < 0.001), but not placebo (r = −0.26 95% CI: −0.62 to 0.18, p = 0.235) (Figure 4)

Summary

Introduction

Soccer is defined as an intermittent sport characterised by periods of high-intensity play in addition to periods of sub-maximal effort over ±90 min. Many studies, which have examined the effect of carbohydrate (CHO) ingestion during simulated/real life soccer matches, have been comprehensively reviewed by Phillips et al [7]. The players in most of these studies ingested 5 mL/kg of a 6%–7% CHO solution prior to exercise, and 2 mL/kg every 15 min during exercise [7] These studies have found that CHO ingestion before and during exercise reduces muscle glycogen utilization [10,11], maintains plasma glucose levels [12], improves running time to fatigue [13,14,15] and coordination [12,14] in the latter stages of the exercise trial. The effects of CHO ingestion on simulated soccer performance have been undertaken in adolescents, the results being similar to those in adults, showing an overall improvement in time to fatigue [16,17]

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Conclusion