Its a catch 22 when you dont' have a lot of experience or training and you want a job and the employer will usually require some sort of resume, so you gotta have something to submit.
You could try something similar to this:
SUMMARY
Highly motivated fitness consultant with experience in fitness center environment. Areas of interest include weight training and fitness, nutrition and supplementation. Ability to establish excellent raport with clients new to fitness concepts and equipment. Skills include communication and attention to customer needs, client training and sales interaction, familiarity with fitness equipment and training concepts, fitness facility day-to-day <or business> activities.
EMPLOYMENT
Delaware Health & Fitness, <location of business> June, 2000 - March, 2001
Client Training Consultant (or Staff Personal Trainer or something)
* Provided custom weight-training and fitness schedules and routines to gym clients
* Interactively guided individual clients through custom weight training and fitness programs
* Worked with many clients referred by in-house chiropractic specialist to support recommended therapeutic exercise regimens.
Acme Markets, <location of business> March, 2000 - June 2000
Grocery Inventory/Stocker, Bagger
* Provided support and assistance to customers with specific questions or needs to ensure satisfaction with their visit.
* Maintain stock availability and presentation for all items.
* Assisted cashier in check out and item bagging, delivery of bags to customers' cars.
RELEVANT SKILLS
* Knowledge of weight training, fitness and nutrition concepts
* Customer care and communication skills
*< any additional stuff you have -- your own training knowledge, or experience in the fitness arena>
EDUCATION
High School Diploma A.I DuPont High School, <town, state> 2002
Because you dont' have training certs, etc in the field you need to promote your work experience and highlight those skills or responsibilities that would be required/of interest to the hiring person for the position you want. In this case, knowledge of equipment, etc. is almost as important as attention to customer service, sales, etc. You could replace the "SUMMARY" section with an objective, though if you are filling out a job application along with presentign the resume, the application form is where you can describe your objective. And there it is appropriate to say you are interested in a front desk or whatever position.
If you want to pursue a career or near-term career in the fitness industry, research some training certs, ask the hiring person if the gym has particular interest in a particular training organization and state that you are pursuing some sort of training or will be soon. (You don't have to lay it on real thick just to give them a warm fuzzy, but take the opportunity to ask what sort of training, etc. they see as useful to advance in the field.)
And of course it would also be useful to have a couple people from your previous gym job to provide recommendations for you -- get their names & contact info for a list of references to be provided upon request by the hiring person.
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