Abstract
The purpose of this study was to assess the effects of sucrose vs. glucose ingestion on postexercise liver and muscle glycogen repletion. Fifteen well-trained male cyclists completed two test days. Each test day started with glycogen-depleting exercise, followed by 5 h of recovery, during which subjects ingested 1.5 g.kg(-1).h(-1) sucrose or glucose. Blood was sampled frequently and C-13 magnetic resonance spectroscopy and imaging were employed 0, 120, and 300 min postexercise to determine liver and muscle glycogen concentrations and liver volume. Results were as follows: Postexercise muscle glycogen concentrations increased significantly from 85 +/- 27 (SD) vs. 86 +/- 35 mmol/l to 140 +/- 23 vs. 136 +/- 26 mmol/l following sucrose and glucose ingestion, respectively (no differences between treatments: P = 0.673). Postexercise liver glycogen concentrations increased significantly from 183 +/- 47 vs. 167 +/- 65 mmol/l to 280 +/- 72 vs. 234 +/- 81 mmol/l following sucrose and glucose ingestion, respectively (time +/- treatment, P = 0.051). Liver volume increased significantly over the 300-min period after sucrose ingestion only (time x treatment, P = 0.001). As a result, total liver glycogen content increased during postexercise recovery to a greater extent in the sucrose treatment (from 53.6 +/- 16.2 to 86.8 +/- 29.0 g) compared with the glucose treatment (49.3 +/- 25.5 to 65.7 +/- 27.1 g; time x treatment, P <0.001), equating to a 3.4 g/h (95% confidence interval: 1.6-5.1 g/h) greater repletion rate with sucrose vs. glucose ingestion. In conclusion, sucrose ingestion (1.5 g.kg(-1).h(-1)) further accelerates postexercise liver, but not muscle glycogen repletion compared with glucose ingestion in trained athletes.
Original language | English |
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Pages (from-to) | 1328-1334 |
Journal | Journal of Applied Physiology |
Volume | 120 |
Issue number | 11 |
DOIs | |
Publication status | Published - 1 Jun 2016 |
Keywords
- C-13 magnetic resonance spectroscopy
- carbohydrate
- recovery
- fructose
- endurance exercise