Of the people with whom I've chatted here, who've said they had good results with Trib, most (if not all) have done so, using extremely high doses (at least 1500 mg per day). Some have gone as high as 3000 mg/day.
The issue I have with these studies is too often they use too low of a dose for the subjects. Then, they claim that Trib doesn't work. MidniteRambo posted a similar study several months ago, which I criticized for that reason.
As for this study, I have a tough time thinking that 2500 mg of Tribulus is going to help a 275-lb (125 kg) guy. He may have to double that amount, to get any kick out of it. 1250 milligrams definitely won't help. And, that's assuming that these guys are, for the most part, athletic.
What was the saponin percentage of the Tribulus used? From what I've read, it has to be at least 40% for the Trib product to be any good. A lot of the super-cheap Trib products have saponins as low as 12%. Other products that get rave reviews (and happen to be a bit more pricey, unless they get marked down at GNC
) have 80% saponins. Nutrex's Vitrix and Nx Care's NITRO T
3 immediately come to mind.