While I was out of town a few months ago I purchased a temporary pass at a big box gym so I could get in some strength training workouts. I'm a trainer, so I notice things going on while others are exercising. I'm always amazed by what I see. To get the most from your training sessions here's two things to keep in mind.
1) Stop talking while you're going through the exercise movement.
If you and the trainer are yapping the same time you're squatting, pulling, pushing, pressing, or rotating how could you possibly be getting the most from that exercise? It's inefficient. While I was doing my workout I watched a trainer and client yapping away while the client haphazardly went through the exercise movements. That should not be happening, the trainer should not partake in a laughing, full blown conversation in the middle of your exercise. Save the talk for when you finish the movement, otherwise you're wasting your time and money while missing the chance to learn how to exercise correctly.
Instead you should be focusing on the movements you're doing. Pay attention to your breathing and when to brace your core. Stay engaged with the exercise. Your trainer should teach you how to do this.
2) Don't feel obligated to do an exercise you're not comfortable with.
If a trainer is asking you to do an exercise that you feel is inappropriate for you than you should speak up. Again, I observed this at the gym. The (young) trainer instructed his client (overweight and middle aged) to do a side plank with her bottom arm straight and hand on a medicine ball (yikes)! Even though she tried a few times, and failed miserably while looking very panicked, he expected her to do it. That's a very advanced move that requires a lot of stability and strength. The client currently had neither. In this case I watched the client take it upon herself to do a front plank instead with the medicine ball under both her hands. It was still very difficult for her, and she barely held it a few seconds, but she changed the exercise to something she thought was more realistic and doable for her. Kudos to her and shame on the trainer.
You know your body better than anyone. If you're uncomfortable doing a certain exercise than you don't have to do it. There are many safe modifications and alternatives to choose from.
Your workouts should be enjoyable and something you look forward to doing. You should feel good when you're done. It's okay to talk during your training sessions, but not as you're going through the movements. And it's always okay for you to question your trainer if a certain exercise is not comfortable for you.
To get the most from your personal training sessions stay engaged with the movements and listen to your body. You're looking for health, wellness, and success. Exercise your body appropriately so you can move better and feel better.
Useful practical information and a workout or two...