Looks great
One thing you might wanna do though is to put a single, slightly more clear descriptive line on the front page. "Online Fitness Training" can sound somewhat abstract, and some surfers are kinda stupid. Making it clear that your site provides info, coaching, and stuff like that might be a good idea.
Also, something that might help are some before/after pics of "members" in the tour. Those might help convince those hard to persuade surfers.
Something you also might want to consider is putting direct links to articles on the main page. That way, people stick around a bit for some free content, and after that they'll be much more likely to join your site.
Oh, and one last idea: you could start a weekly/biweekly newsletter with some free health/training tips, and ofcourse some signup links
