Bar height on a mountain bike is more about bike handling than speed. Bars that are too low with a long reach make descending more difficult. Bars that are too high and close make it easier for the front wheel to come off the ground while climbing.
If you have space to "slouch" the bars are probably already too close but without seeing a picture, who knows? I know a ton of young male racers that can provide good fit/position advice to a woman on a mtb. He was probably concerned about bike handling more than anything.
Last edited by SadieKate; 06-11-2012 at 12:41 PM.
Frends know gud humors when dey is hear it. ~ Da Crockydiles of ZZE.