It's just past New Year's Day, so the TV and radio are filled with ads for gyms and diets.
I heard a radio commercial yesterday for a gym offering bring you in, give you a consultation and train you to use all those machines they have. I heard it on the way home from the warehouse gym I train at, whose most advanced exercise machines are a multi-pulley cable station.
All I could think was, "That's exactly what you don't need."
All you really need to get stronger is your own body, and at least one of - a barbell and weights, a set of dumbbells, a set of kettlebells, or some kind of improvised version of any of those three. That's it. You're better off with those than with the machines. Free weights are superior to machines for building strength and athleticism.
Why is that?
Machines force your body into a specific path. By design, machines force you to conform to their range-of-motion (ROM). If that range of motion is not ideal for your body (possibly, for anyone's body), you will still have to take the weight through it. While you don't have to worry about dropping the bar on a machine, or losing your balance with a barbell, or whatever, you trade that tiny risk of traumatic injury for the slow grind of accumulated injury from going through an unsafe ROM.
Machines stabilize the weight for you. This gives you a false sense of strength and safety. You can lift a bit more weight on a machine than on a similar barbell or dumbbell exercise, because the machine keeps the weight on track. You just need to move it, it can't freely move side to side and thus you don't have to keep it stable. Why is that bad? Because any real-world application of strength - picking up your granddaughter, lifting a big rock, shoveling snow, tackling another player in a game, etc. - will be done without the stabilization. You need to train that stabilization to avoid injury. You can get stronger on a machine, but it will be incomplete strength - and when push comes to shove, it won't get you as far as a lighter weight on a free weight will. You can lift heavier on a machine, but the lighter free weight will get you more strength, more power, and more resistance to injury.
Machines work the muscles in isolation. More correctly, most machines do so. A few allow for compound exercises, which exercise more than one joint at once. But most of them isolate a specific muscle. That's fine for certain circumstances - medical rehabilitation, for example, testing of specific muscle strengths for research purposes, for for competetive bodybuilders trying to achieve valuable muscle symmetry. But if you're not rehabilitating an injury under professional supervision, doing research, or doing the final touches on your build for a contest, you don't want these machines. There is a place for isolation exercises in your workout, and it's after the compound work that will give you most of your strength and fitness gains. Stick to free weights and cables! Even Arnold got ready for competition in Pumping Iron with free weights. Not a lot of pec machine work, but plenty of squats!
Machines are inefficient. For example, compare doing a squat with working your legs. You can either the leg curl machine, the leg extension machine, the leg press, and possibly do cable kick-backs for your glutes...or just do a set of squats. The second takes less time, allows a normal range of motion, and works all of your muscles together in a motion you need to live (squatting down and back up, with or without resistance). Standing up from a chair is nothing more than a bottom-up box squat, weighted if you do it holding your niece or nephew. What standing up from a chair is not a combination of 4-5 machine exercises. The squats will even involve additional muscles beyond the prime movers, so it's giving you even more bang for the buck.
So when I hear them promise to teach us exercisers to use all those machines, I just want to cringe. That's the last thing we need. We need the basics - a weight and the willingness to move it, and the instruction to move it correctly. We don't need expensive machines to get strong. Save the machine (your car) for driving to the gym or the sporting good store.