From just reading the ncbi blurb, a couple things stand out:
only 10 total subjects, 5 each treatment (bad sign)
no mention of how they were chosen, but it was probably pretty stringent since the time to exhaustion numbers were pretty close (a good sign)
pretty big difference in time till exhaustion (interesting)
without reading the rest, I can't interpret the significance of the other findings
no obvious mechanism for performance increase - not what they thought

So...it certainly isn't a very strong study, but perhaps not incorrect. It might be enough to give it a whirl if you are so interested?