Nowadays with the advent of the age of technology it’d probably be unnatural if an increasingly important chapter of everyday existence - like staying fit - would fail to take advantage of its benefits.
Fitness-Machines, once piles of rusty iron pipes welded together, have become ever present. The levels of sophistication fitness equipments have reached is quite unprecedented. And it does work.
As specialized companies use up resources and manpower on a never before seen scale to develop specialized machines, results don’t fail to show up every step of the way.
One of the most important advantages machines provide over free-weights, is the fact that they provide continuous resistance and thus, theoretically, they can work a muscle more on a full range of motion than free-weights can. At first glance - especially after soaking in a good daily dose of tele-shopping infomercials, regarding newly invented fitness devices that promise huge muscle gains and fat losses, in 5 min workouts per day - one would even consider the question:” why are there so many dumbbells and barbells left in gyms then? They’re obviously obsolete. Why do these companies keep producing them?”
Well, apparently the human body is designed to work more against gravity than anything else. And you’d do better to forget about the 5 min/day workout with superb results, because that‘s just not going to happen.
The resistance the human muscle encounters during workout with free-weights, is a complex one, unlike the single-plain resistance machines provide. The balancing of the weight and its lifting against gravity provide the most in muscle-mass gain. According to scientific studies, complex lifting exercises (like the squat), in which more muscle-groups are involved, have as direct result an increase in the levels of testosterone in the body. The more testosterone you have, the bigger the muscle you build.
All of this would explain why you never see a professional bodybuilder working out in the gym using predominantly machines. Some machines are indeed needed, no doubt about it, as they’re peculiarly useful in some muscle groups, however, they’re mostly good for definition and sculpting, rather than laying down the raw mass. Such machines are the leg extension machine, pec-deck and cables.
An ideal workout would feature somewhere around 70 percent free weight exercises and the rest machines. Since - as said before - beginners ought to stick to basics, a more free-weight dominated program is better suited for their needs. All basic exercises ( benchpress) are done with free-weights and they’re all well known as particularly efficient mass-boosters.