In the battle between free weights vs machines there is really no contest, free weights win hands down.
Now, I'm not some weight room elitist.
I've used both free weights and machines and I have to admit that machines are nice if you just want to move a pin instead of stack and unstack weights.
But, ultimately it's about results and you just can't get the same results with machines.
That's because you can't do compound or whole body exercises with a machine.
These are things like the clean and jerk, military press, bench press, dead lift, squats and others.
Sure there are machines that mimic some of those exercises but they limit your range of motion and you don't get the true benefit of the real exercise.
The benefits of compound exercises are multifold.
First, they work your body the way it was meant to be worked as a complete holistic unit.
Second they build muscle and the more muscle you have the more fat you will burn.
Thirdly, they cause you to exert so much effort that you will go into a state of metabolic shock and be burning calories at a higher rate for long after the workout is over.
Those are the physical benefits but there are some more subtle benefits as well.
You will instantly gain "street cred" so to speak if you are seen picking a barbell off the floor, jerking it to your chest and raising it high over head.
How many people are at the gym doing that?