You’ve already received some good advice with regard to finding your niche with the wording of your brochure, and that is great.
I’d like to add two more ideas:
1. Include images in your brochure. Nothing is more powerful than a picture. It speaks a thousand words and people can automatically relate to it. Do you have any photographs of you helping your clients who may be overweight and/or deconditioned? Potential clients may relate to you (and perhaps be motivated) if they happen to see you at work helping someone in a compassionate and caring way.
2. Think about adding some testimonials from your clients. This will give potential clients actual results they can see–and word of mouth is one of your best marketing tools.
Just a thought! Good luck with your brochure.