Here's an article that verifies that its necessary to take in a large amount of HI GI carbs after a workout.
Effect of carbohydrate ingestion on glycogen resynthesis in human liver and skeletal muscle, measured by 13C MRS
Anna Casey1, Rob Mann2, Katie Banister2, John Fox1, Peter G. Morris2, Ian A. Macdonald1, and Paul L. Greenhaff1
1 School of Biomedical Sciences, University of Nottingham Medical School, Nottingham NG7 2UH; and 2 Department of Physics, Magnetic Resonance Centre, University of Nottingham, Nottingham NG7 2RD, United Kingdom
This study investigated the effect of carbohydrate (CHO) ingestion on postexercise glycogen resynthesis, measured simultaneously in liver and muscle (n = 6) by 13C magnetic resonance spectroscopy, and subsequent exercise capacity (n = 10). Subjects cycled at 70% maximal oxygen uptake for 83 ± 8 min on six separate occasions. At the end of exercise, subjects ingested 1 g/kg body mass (BM) glucose, sucrose, or placebo (control). Resynthesis of glycogen over a 4-h period after treatment ingestion was measured on the first three occasions, and subsequent exercise capacity was measured on occasions four through six. No glycogen was resynthesized during the control trial. Liver glycogen resynthesis was evident after glucose (13 ± 8 g) and sucrose (25 ± 5 g) ingestion, both of which were different from control (P < 0.01). No significant differences in muscle glycogen resynthesis were found among trials. A relationship between the CHO load (g) and change in liver glycogen content (g) was evident after 30, 90, 150, and 210 min of recovery (r = 0.59-0.79, P < 0.05). Furthermore, a modest relationship existed between change in liver glycogen content (g) and subsequent exercise capacity (r = 0.53, P < 0.05). However, no significant difference in mean exercise time was found (control: 35 ± 5, glucose: 40 ± 5, and sucrose: 46 ± 6 min). Therefore, 1 g/kg BM glucose or sucrose is sufficient to initiate postexercise liver glycogen resynthesis, which contributes to subsequent exercise capacity, but not muscle glycogen resynthesis.
Effect of carbohydrate ingestion on glycogen resynthesis in human liver and skeletal muscle, measured by 13C MRS
Anna Casey1, Rob Mann2, Katie Banister2, John Fox1, Peter G. Morris2, Ian A. Macdonald1, and Paul L. Greenhaff1
1 School of Biomedical Sciences, University of Nottingham Medical School, Nottingham NG7 2UH; and 2 Department of Physics, Magnetic Resonance Centre, University of Nottingham, Nottingham NG7 2RD, United Kingdom
This study investigated the effect of carbohydrate (CHO) ingestion on postexercise glycogen resynthesis, measured simultaneously in liver and muscle (n = 6) by 13C magnetic resonance spectroscopy, and subsequent exercise capacity (n = 10). Subjects cycled at 70% maximal oxygen uptake for 83 ± 8 min on six separate occasions. At the end of exercise, subjects ingested 1 g/kg body mass (BM) glucose, sucrose, or placebo (control). Resynthesis of glycogen over a 4-h period after treatment ingestion was measured on the first three occasions, and subsequent exercise capacity was measured on occasions four through six. No glycogen was resynthesized during the control trial. Liver glycogen resynthesis was evident after glucose (13 ± 8 g) and sucrose (25 ± 5 g) ingestion, both of which were different from control (P < 0.01). No significant differences in muscle glycogen resynthesis were found among trials. A relationship between the CHO load (g) and change in liver glycogen content (g) was evident after 30, 90, 150, and 210 min of recovery (r = 0.59-0.79, P < 0.05). Furthermore, a modest relationship existed between change in liver glycogen content (g) and subsequent exercise capacity (r = 0.53, P < 0.05). However, no significant difference in mean exercise time was found (control: 35 ± 5, glucose: 40 ± 5, and sucrose: 46 ± 6 min). Therefore, 1 g/kg BM glucose or sucrose is sufficient to initiate postexercise liver glycogen resynthesis, which contributes to subsequent exercise capacity, but not muscle glycogen resynthesis.