King Grub
2010-04-21, 10:01
The ingestion of carbohydrate (CHO) solutions has been shown to increase CHO oxidation and improve endurance performance. However, the majority of studies have investigated CHO in solution and sporting practice includes ingestion of CHO in solid (e.g. energy bars) as well as liquid form. It remains unknown whether CHO in solid form is as effectively oxidized as compared to CHO solutions.
PURPOSE:: To investigate exogenous CHO oxidation from CHO provided in either solid (BAR) or solution (DRINK) form during cycling.
METHODS:: Eight well trained subjects (31+/-7 yrs; 73+/-5 kg; 1.79+/-0.05 m; VO2max: 69+/-6 ml/kg/min) cycled at 58+/-4% VO2max for 180 min while receiving one of the following three treatments in randomized order: BAR plus water, DRINK, or water. The BAR and DRINK delivered glucose+fructose (GLU+FRC) in a ratio of 2:1 at a rate of 1.55 g/min and fluid intake was matched between treatments.
RESULTS:: During the final 2 h of exercise overall mean exogenous CHO oxidation rate was -0.11 g/min lower in BAR (95% confidence interval: -0.27 to 0.05 g/min; p=0.19) relative to DRINK; exogenous CHO oxidation rates were 15% lower in BAR (p<0.05) at 120, 135, and 150 min of exercise. Peak exogenous CHO oxidation rates were high in both conditions (BAR: 1.25+/-0.15 g/min, DRINK: 1.34+/-0.27 g/min), but were not significantly different (p=0.36) between treatments (mean difference: -0.9 g/min, 95% confidence interval: -0.32 to 0.13 g/min).
CONCLUSION:: The present study demonstrates that a GLU+FRC mix administered as a solid BAR during cycling can lead to high mean and peak exogenous CHO oxidation rates (>1g/min). The GLU+FRC mix ingested in form of a solid BAR resulted in similar average and peak exogenous CHO oxidation rates and showed similar oxidation efficiencies as a DRINK. These findings suggest that CHO from a solid BAR is effectively oxidized during exercise and can be a practical form of supplementation alongside other forms of CHO.
Med Sci Sports Exerc. 2010 Mar 19. Oxidation of Solid versus Liquid Carbohydrate Sources during Exercise.
PURPOSE:: To investigate exogenous CHO oxidation from CHO provided in either solid (BAR) or solution (DRINK) form during cycling.
METHODS:: Eight well trained subjects (31+/-7 yrs; 73+/-5 kg; 1.79+/-0.05 m; VO2max: 69+/-6 ml/kg/min) cycled at 58+/-4% VO2max for 180 min while receiving one of the following three treatments in randomized order: BAR plus water, DRINK, or water. The BAR and DRINK delivered glucose+fructose (GLU+FRC) in a ratio of 2:1 at a rate of 1.55 g/min and fluid intake was matched between treatments.
RESULTS:: During the final 2 h of exercise overall mean exogenous CHO oxidation rate was -0.11 g/min lower in BAR (95% confidence interval: -0.27 to 0.05 g/min; p=0.19) relative to DRINK; exogenous CHO oxidation rates were 15% lower in BAR (p<0.05) at 120, 135, and 150 min of exercise. Peak exogenous CHO oxidation rates were high in both conditions (BAR: 1.25+/-0.15 g/min, DRINK: 1.34+/-0.27 g/min), but were not significantly different (p=0.36) between treatments (mean difference: -0.9 g/min, 95% confidence interval: -0.32 to 0.13 g/min).
CONCLUSION:: The present study demonstrates that a GLU+FRC mix administered as a solid BAR during cycling can lead to high mean and peak exogenous CHO oxidation rates (>1g/min). The GLU+FRC mix ingested in form of a solid BAR resulted in similar average and peak exogenous CHO oxidation rates and showed similar oxidation efficiencies as a DRINK. These findings suggest that CHO from a solid BAR is effectively oxidized during exercise and can be a practical form of supplementation alongside other forms of CHO.
Med Sci Sports Exerc. 2010 Mar 19. Oxidation of Solid versus Liquid Carbohydrate Sources during Exercise.