Goji polysaccharides enhance endurance
Sugar chains in goji berries - scientific name Lycium barbarum - protect cells against the effects of extreme exertion and can boost endurance capacity by fifty percent. This discovery was made by researchers at the department of Physical Education and Military Training at the Zhejiang University of Technology, China.


Goji extracts have been recognised as 'botanical medicine' in China since 1983. In traditional Chinese medicine goji is a substance that balances 'yin' and 'yang'.Western studies suggest that goji may protect against cancer, diabetes and cardiovascular disease, and that it may improve the condition of healthy people. In 2000 Chinese researchers published the results of a study which indicate that sugar chains, or polysaccharides, in goji berries cause the latter effect. [Wei Sheng Yan Jiu. 2000 Mar 30;29(2):115-7.]
An animal study published a few months ago in the International Journal of Molecular Sciences builds on the previously mentioned publication. The researchers gave male rats either nothing or increasing doses of goji-polysaccharides [LBP] for 28 days. The amounts are shown in the table below.

The human equivalent of the tested doses of LT, MD and HD was approximately 1, 2 and 4 grams of goji polysaccharides per day. We don't know exactly how many grams of dried goji berry that is.
On day 21 the rats started a training period in which they had to run on a treadmill for 15-20 minutes on a number of occasions.


On day 28 the rats had to run to the point of exhaustion. The researchers put the animals on a treadmill, where they had to run at a speed that caused them to use about 75 percent of their VO2max. As the table above shows, supplementation with goji-polysaccharides extended the amount of time the rats were able to run.After the exertion test the concentration of malondialdehyde [MDA] had risen by less in the goji groups than in the control group. Malondialdehyde is produced when free radicals released during processes of combustion damage the cell membranes. Malondialdehyde is an aggressive and toxic compound.

It looks as though goji-saccharides boost the activity of antioxidant enzymes like super-oxide-dismutase [SOD] and glutathione peroxidase [GPX]. These hold in check the increase in aggressive molecules as a result of exertion.
Int J Mol Sci. 2011 Feb 9;12(2):1081-8.