Now, I can already here the “Bow flex” crowd crying foul, but if you really want to build the muscle density, strength and symmetry that it takes to have Truly Awesome Arms(TM), you simply can’t get there without using free weights. Ever since weight training machines came on the scene, there’s been a tendency among beginning bodybuilders to believe that those stretchy cables and shiny handles must be better than clunky old dumbbells for building impressive arms.
This belief comes partly from slick advertising and partly from inexperience. But the bottom line is that, although arm training machines are very useful for adding shape to your biceps, triceps and forearms, these machines are not particularly efficient for building muscle mass or power. Indeed when it comes to adding size and strength to your arms, free weights are clearly better than machines for the following reasons.
First, have you ever noticed that no matter what exercise you may use for comparison, whether its preacher curls, triceps extensions or parallel bar dips, you can always work with more weight on a machine than you can when using free weights? The reason for this discrepancy is simple – the machine assists you in completing these exercises in a way that free weights do not!
When you train your arms with free weights, your biceps, triceps and forearms must provide all of the power required to complete the exercise motion. Your arms must provide the strength required to overcome gravity, balance the weight and force it to curl upward or extend outward. Unlike the machines, free weights don’t have any cables, strings, bolts or shiny handles to ease you through your biceps curls or triceps extensions.
Second, while free weights allow you to control the resistance angle and range of motion during a given exercise, machines provide no such freedom of movement. For example, I’ve done preacher curls with a machine and with free weights and there is absolutely no comparison between these exercises in terms of resistance angle and range of motion. The free weights are far superior, whether using an EX Curl bar or dumbbells, for building biceps mass and power with preacher curls. The same applies to doing triceps extensions with dumbbells or an EX Curl bar versus doing them on a triceps extension machine. The free weights put much more resistance on the triceps and allow a greater range of motion to complete this exercise. This increased resistance and range of motion recruits more muscle fibers during each extension of the weight, which in turn forces the triceps to work harder and grow faster than they will with machine extensions.
Again, I’m not saying that arm training machines are completely useless when it comes to workout variety or shaping movements. Machines are also very useful for high repetition workouts or advanced training with descending sets, super sets and giant sets. But for building mass and power in your biceps, triceps and forearms in the early stages of your training, you must focus these efforts on working primarily with free weights. So when trying to decide whether to use machines or free weights in your next arm building workout, even though they don’t look as fancy as those shiny machines, you’re better off working with the clunky old dumbbells.