April 1, 2011
Fructose and Galactose Enhance Postexercise Human Liver Glycogen Resynthesis

It is believed that strategies that enhance liver glycogen post-exercise will increase exercise capacity in a subsequent exercise bout, and that the liver restores glycogen as a first priortiy over skeletal muscle when carbohydrates are available post-exercise.  Similar to my previous post, researchers wished to sort out which combinations of carbohydrate sources better replenished liver glycogen stores.

Conclusion:  This study demonstrates that ingestion of ~70 g·h-1 of maltodextrin + fructose (2:1) or maltodextrin + galactose (2:1) drinks consumed during the short-term post-exercise recovery results in a two-fold increase in the rates of liver glycogen replenishment compared to an iso-energetic, iso-osmotic maltodextrin + glucose control.

My input:  This is the first study of its kind to look at liver glycogen resynthesis with novel MRI tracer techniques.  They did note that galactose does cause some stomach upset in the cyclists.  However, whole body glycogen storage seems to be more effective when fructose is present, possibly making it the best carbohydrate source.

Practicality:  Carbohydrate drinks containing fructose and galactose could help in situations where athletes have to exercise twice in one day with relatively little recovery.

Décombaz et al MSSE March 2011

  1. exercisescience posted this