If you’re thinking of becoming a personal trainer the most important thing to ask is whether it is something you really want to do, something you are passionate about. If not, find what that thing is and do it instead. You only live once and you shouldn’t waste years of your life in a job you don’t enjoy.
Personal training is teaching. Spend at least as much time learning how to teach as you do learning about exercise and nutrition. All the training and diet knowledge in the world won’t do your clients any good if you don’t know how to effectively communicate it.
How you say something is just as important as what you say. Choose your words and phrasing carefully, especially when instructing someone during an exercise. Be specific, be concise, and whenever possible phrase things positively. Don’t tell them what they’re doing wrong – tell them how to do it right.
Keep records of your clients’s workouts and goal-specific measurements. If you aren’t tracking these things you’re not serious about helping them improve them.
Learn to market and sell. You can be the best personal trainer in the world and it won’t make a difference if people don’t know about you.
Be an instructor, not a rep counter. Anybody can load plates on a bar or put a pin in a weight stack and stand there counting reps and shouting encouragement. A good trainer also carefully observes and analyzes the client’s performance and instructs them on how to improve it to maximize the benefit and minimize the risk of the exercise.
Lead by example. You don’t have to be a bodybuilder, model, or elite athlete to be a good trainer (and being one doesn’t make you a qualified trainer either) but you should “walk the talk”. Being fit and healthy inspires confidence in your ability to teach others to do the same.
Focus on principles, not programs. Individuals vary in their response to exercise and diet and their goals. No one specific program or diet will work best for everyone, but the general principles of exercise and nutrition are universal. Learn to adapt them to the individual.
First, do no harm. The safety of your clients should be your highest priority. Whatever their stated training and nutrition goals the end goal is always to improve their well being and enjoyment of life, and injuring them or undermining their long term health is counterproductive to that.
“Absorb what is useful, reject what is useless, add what is specifically your own.” – Bruce Lee, paraphrasing Jiddu Krishnamurti. Every trainer is different, every client is different, and you will find some ways of doing things (teaching, instructing, recording workouts, marketing, accounting, etc.) work well for you, others don’t, and some may work well with certain clients and not others. Read, listen, observe and talk with other trainers and don’t be afraid to experiment to find ways to do things better or improve yourself as a trainer.