Last week, we discussed how weight belts may not be quite as useful as they proclaim. Inspired by that, here are a couple other common gym...things...that I just can't get behind.
Squatting in the Smith Machine
The #1 reason I hear for squatting in the Smith Machine is some version of “it's better for your knees.” Whether it's that the machine is better or using free weights is worse, it's the same (incorrect) conclusion.
In truth, squatting poorly is bad for your knees, while squatting well is perfectly fine. The two key points people seem to miss are that they don't take the time to learn [or are shown incorrectly] how to squat properly, or that they haven't prepared their bodies to move through the correct positions.
I would actually argue that Smith Machine squats can be worse for your joints than with free weights. Unless you know exactly how to move and are capable of doing so, a Smith Machine will allow you to push in all sorts of directions other than straight up, which can put some undue strain on your joints.
If you are able to move through a squat pattern well, there’s not much need for a Smith Machine. If you are not able to, a Smith Machine will not teach you.
Wearing Weightlifting Shoes
I feel the need, again, to mention that context plays a role here. If your goal is to lift a lot of weight for the sake of lifting a lot of weight, go for it.
But in the context of improved health, fitness, and vitality, weightlifting shoes are really no different than belts: they claim to help you lift more, but really what they're doing is making up for a limitation or shortcoming that you can—and should!—work to correct.
The shortcoming is mainly in your ankle mobility (secondarily in your movement pattern). Wearing weightlifting shoes lifts your heels off the ground, which allows your legs to translate forward more while keeping your weight on your heels. Blah blah blah, body mechanics and such...the point I’m trying to make is that you shouldn't take the benefits of this (or any) product at their word. Ask questions, figure out what’s really going on, and make an informed decision about whether weightlifting shoes are for you.
Some folks propose using them as an interim measure to help progress your squats while working on your mobility. While I'm down with that approach, be warned that weightlifting shoes can be quite costly, especially for a temporary fix.
[Weightlifting shoes also provide a very rigid, strong base of support due to their shape and hard soles. But outside of the context of competition, it would serve you better to develop that stability rather than use a tool to fake it.]
All I’m really trying to do here is get you thinking and asking questions. Relying on conventional wisdom and taking any sort of benefit claim for granted can lead you to trouble. But don't take my word for it! Poke around and draw your own conclusions.