Five Ways to Spot a Lousy Personal Trainer

Two of your best friends hired trainers and now they love their workouts. And there's another story in the gossip magazines about an amazingly fit celebrity who thanks her trainer by name. It's about time, you decide, that you get some help yourself. But before you choose your coach, make sure you know what to look for. Yes, it's nice that a prospective personal trainer looks healthy (or handsome), but that's not enough. If you spot any of these five danger signs, physiologist Cedric Bryant of the American Council on Exercise suggests you keep looking.

1. Unprofessional Business Practices: If your trainer doesn't explain his cancellation policies, can't provide references, or doesn't have liability insurance, walk away. These are all signs that a trainer isn't a professional. Most importantly, ask where your trainer got his or her certification: Besides the American Council on Exercise, the American College of Sports Medicine and National Strength and Conditioning Association are the leading fitness certification organizations.

2. The Cling Factor: When you ask how many sessions it should take before you can work out on your own, if the trainer gives a vague answer or tells you about clients he's been seeing weekly for a year or more, be wary. A good trainer will teach you to be independent, he won't cling to your business. After four months, you should be able to set up and operate equipment on your own, use proper technique and monitor your exercise intensity. You can always have a tune-up session later if you plateau or get bored.

3. Diet Know-it-All: The trainer tries to sell you vitamins or protein powder, recommends unusual products, or tells you, you can't eat meat. Trainers are taught basic nutrition and weight-management techniques, but they shouldn't be pushing an agenda about diet or supplements.

4. The Marine: The trainer pushes you too hard. You need to exercise past your comfort zone in order to build stamina and muscles. But it is possible to overdo workouts. If you start to hate your workout, feel chronically sore, or your heart rate stays high well after a round of exercise, you may be over-exercising. Losing your appetite, sleeping badly, or becoming depressed are other possible symptoms of overtraining. If you're not feeling better as a result of your workouts—stronger and more energetic—complain. Or move on.

5. Personality Clash: You just don't like or trust this person. You need to feel comfortable and sure that he or she won't gossip about you or overstep boundaries by talking about other clients, flirting, or telling you more than you want to know.