To someone getting started with exercise, a personal trainer can be extremely valuable. There is nothing like having an expert provide hands-on advice on the proper way to perform lifts like squats and deadlifts, for instance. However, there are also many pitfalls when hiring a personal trainer.
One is basic competence. Anyone can claim to be a personal trainer. I could claim to be a personal trainer, and probably with better cause than most. But that doesn’t mean you should pay me $50/hour for fitness advice, even if I didn’t give it all away for free here anyway. And even if somebody has a credible-looking certificate on their wall, they could still be a complete dummy.
Another pitfall is that many personal trainers give advice based on what they think their customers want to hear, rather than what their customers actually need to hear. This is like a mechanic choosing what oil filter to put on your car based on how pretty you think it is, rather than how well it filters oil. It makes absolutely no sense.
For instance, a personal trainer would have to be criminally ignorant to not know that exercises with freeweights are much better for almost everyone than machine exercises. This is an objective, quantifiable fact that anyone with a basic understanding of exercise physiology can instantly grasp. So why do so many personal trainers put their customers on machine routines? The answer is simple: the customers like the machine routines better. Machines are modern and pretty and not as threatening as dirty, primitive barbells and dumbbells. The machine produces inferior results for the same amount of effort put into it, but the customer doesn’t know that, so he is predisposed to like the machine, and be happy that his trainer has put him on it..
The problem here is that the customer’s preference is based on their ignorance, which it is the job of the personal trainer to correct, not cater to. If you explain to a rational person that one method produces better results for the same investment in time & effort than the other, they are going to opt for the better method every time. But that explanation requires an effort that most personal trainers seem unwilling to make, and their customers suffer for it.
Another example of this is spot reduction. No personal trainer with half a brain believes that you can make the fat on your gut disappear by doing sit-ups. Yet it seems like many of them are still producing what look suspiciously like spot reduction workouts. They talk about “sculpting” and “toning” their customers’ bodies, even though these are completely meaningless terms that have no relationship to what diet and exercise actually do to the human body.
Why do they do this? Because it is what their customers want to hear and expect to get. It is easier to give someone a garbage routine that aligns with their preconceptions, rather than explain to them why doing something completely different would be much more beneficial for them.
Many personal trainers also seem to completely neglect diet, even though it is virtually impossible to “work off” the consequences of a very bad diet. It is practically impossible to exercise enough to compensate for a bad diet; it would simply take too long to burn off that many calories. But confronting your customers about their diet can be a touchy subject, to say the least, so most trainers simply ignore it.
Paradoxically, another problem of personal trainers is that they often devise routines that resemble medieval torture more than a rational exercise program. Some possible motives include making the most of limited time with the customer, playing to misguided customer expectations of what a “good workout” looks like, or just plain macho idiocy. Regardless of the motive, the result is often destructive, because it leads the customer to conclude that exercise is an inherently painful activity.