Physiological Impact of a Single Serving Slow Absorption Carbohydrate on Metabolic, Hemodynamic, and Performance Markers in Endurance Athletes During a Bout of Exercise

Abstract

Davitt, PM, Saenz, C, Hartman, T, Barone, P, and Estremera, S. Physiological impact of a single serving slow absorption carbohydrate on metabolic, hemodynamic, and performance markers in endurance athletes during a bout of exercise. J Strength Cond Res 35(5): 1262–1272, 2021—The purpose of this study was to determine how a slow-absorbing carbohydrate affected markers of metabolism, hemodynamics, and performance in well-trained endurance athletes. We examined total and exogenous carbohydrate oxidation (CHO ox), glucose, and performance after consuming different glucose beverages, before a treadmill run. Ten male runners (32.4 years; V̇o 2max, 55.9 ml·kg−1·min−1) participated on 3 occasions: slow digestion CHO (S), fast digestion CHO (F), and water (W). Subjects consumed a 50 g dose of either S or F before a 3-hour treadmill run at 57% V̇o 2max. Variables were assessed at −15, 0, 30, 60, 90, 135, and 180 minutes. Immediately postrun, subjects completed a time-to-fatigue test at 110% V̇o 2max. There was a significant difference in CHO ox for W vs. F and S (C,1.14; S,1.52; F,1.66 ± 0.2 g·min−1, p < 0.05). Fat ox was significantly higher in S vs. F (S,0.54; F,0.47 ± 0.08 g·min−1, p < 0.05). Exogenous CHO ox was significantly higher in F vs. S (F,0.26; S,0.19 + 0.04 g·min−1, p < 0.05). There was a significant difference in average blood glucose for trial (F,94.5; S,97.1 vs. W,88.4 + 2.1 mg·dl−1) and time × trial for F vs. S (0 minutes, p < 0.05). There were no significant performance differences. Consumption of a single bolus of CHO beverage before a 3-hour run elicits significant alterations in energy metabolism compared with just water, with S CHO oxidizing significantly more fat than a rapidly digested carbohydrate. These findings suggest that slow-digesting modified starch provides a consistent blood glucose level and sustained exogenous energy supply during a sustained, 3-hour endurance run. Significance was set at p < 0.05.

Effects of the Timing of Carbohydrate Intake on Metabolism and Performance in Soccer Players

“…Therefore, subjects recognized the mixed and pre-exercise test as having a relatively low exercise intensity compared to the placebo or half-time test in the first half of the exercise protocol. It is commonly believed that increasing fat utilization and sparing CHO are associated with increased endurance [ 27 , 28 , 29 ]. Previous studies of long-distance athletes have shown that carbohydrates consumed during exercise increase fat oxidation rates during exercise [ 30 ].…”

Effects of Osmolality of Rice Sports Drinks on Sports Performance

“…2014). According to Davitt et al(11), a slow-digesting modi ed starch maintains a stable blood glucose level and an external energy supply during a 3-hour endurance run. The researchers used cornderived carbohydrate drinks with 13C-isotopic enrichment of the glucose molecules in their investigation.…”