Weight machines take many alignment questions out of the picture. When you adjust the machine to fit your body correctly, your body is supported and is only allowed to perform a specific movement pattern. Your stabilizers do not need to work as hard. You do not need as much coordination. This makes it less likely that you will injure yourself. However, you do not receive the extra training benefit of challenging your balance and coordination. multihead weigher
Weight machines isolate specific muscle groups. Since you are structurally supported and can only perform one range of motion, you can target a muscle in a way that is not possible with free weights. This design flexibility overcomes some of the limitations of free weights that can only use the force of gravity and body positioning. Some experts argue that this specificity of design is good, since you can fine tune your training on a particular muscle. Others argue that this is not functional and that our bodies do not move this way.
Since machines are designed to target muscle groups precisely, they do not permit much versatility. The number of possible exercises therefore is much fewer than the possible exercises with free weights. This lack of training variety may contribute to boredom. Furthermore, since you need so many different machines to perform a total body workout, it is both expensive and requires a lot of space.
Another advantage of machines is that you can perform your workout routine quickly and efficiently. Machines are usually organized in the same sequence that you would perform your exercises. You do not have to think as much about what exercise to do next. You travel from one machine to the next, adjust for fit, insert your pin and go. In gyms with electronic equipment, the machines even remind you of your routine at each station.
Many weight machines provide variable resistance. The machine ideally presents proportionally less resistance in weaker muscle positions and more resistance in stronger muscle positions. For people who are particularly weak, this can facilitate training. Without this variability, you are limited to what you can lift at your weakest point. For people seeking maximal resistance, this may permit maximal challenges.
With machines, the weight stacks or source of resistance is secure. You are much less likely to injure yourself. You need to exercise care when you are placing and removing your pin, and ensure that you never put your fingers between the weight plates. Other than that, it is not likely you will drop the weights on yourself. The risk of this happening with free weights is much greater