Anyone who has ever been in a gym before is familiar with
gleaming banks of shiny exercise machines. Coming in all shapes and sizes, they are usually cause for newcomer to gym to pause and ask, "What IS all of that stuff?" Well, according to price that gym paid for any one piece of that equipment, I certainly hope that it not only stimulates your muscles, but also cooks your breakfast, washes your car, and brings kids home from soccer practice! Now question becomes whether or not those machines were worth price, or if you'd be better off doing a home aerobics video with a can of soup in each hand….
Personally, I would advise you to get low-sodium version of soup, serve it up alongside a tomato sandwich, and then go buy yourself some free weights. Yes, that is just my opinion, but it does come with some scientific reasoning behind it.
Natural movement vs. Controlled movement
One of things that you need to remember is that when you are exercising, you are training for LIFE. You may spend an hour a day at gym, but that still leaves 23 other hours for your muscles to function without aid of that fancy equipment.
Whenever you do any given exercise, movement of your body during that exercise is called Range of Motion. The greater and more difficult Range of Motion, more effective exercise is, because your body has to work harder to perform that movement.
Let's take a classic dumbbell bicep curl for our case study. If you aren't familiar with movement, it is basically performed by standing up straight with your palms facing forward, and a pair of dumbbells held down at your sides. You concentrically contract your biceps (also known as flexing your elbow) to bring dumbbells up to approximately shoulder level, and then repeat movement for a prescribed number of repetitions.
Let's take that same muscle movement and do it using a bicep curl machine. You sit down, brace your upper arms on a pad, grasp 2 handles that are in front of you, and do that same fancy elbow flexing movement to move handles in an upward motion. Pretty easy stuff so far, right?
Now let's examine muscles that are used in this motion. Wait - I thought we were concentrically contracting biceps? That is correct, and if you are using bicep curl machine, that is pretty much ALL you are doing. For one, you are sitting down. You know, like you did all day at work, and then in your car on way to gym. Then, your upper arms are braced on a nice soft pad to keep your upper body stable while you pull handles upwards. The machine has effectively limited muscles used in this exercise to biceps, as well as muscles in your forearms and fingers as you grip handles.
