So what are free weights? Any object that is not fixed to a set of axis is a free weight. This could be a dumbbell, barbell, medicine balls, physio balls, kettle bells, ankle weights, or even your own body weight. Each of these can move through various planes in all three dimensions. Weight machines involve various combinations of pulleys, cams, and lever arms working from a set axis. A set axis means they work from a fixed range of motion.
Free weights provide a constant resistance during an exercise. It doesn’t matter the position- lifting 5lbs is lifting 5lbs. However, the weight you actually lift on a weight machine changes depending on the length of the lever arm. This can work in your favor, especially if you are recovering from an injury. The lever arm will make lifting the weight easier for a weaker joint and harder for a stronger joint. So depending on your goal, both are beneficial. Most weight machines target a specific muscle, also aiding in rehabilitation from an injury. This isn’t as beneficial if you are looking for more functional movements, though. While weight machines isolate a muscle, free weights can help you target and indirectly work other muscles. Since free weights aren’t in a fixed plane and allow for three dimensional movements, muscles have to control the movement.
Since machine weights work on a system of pulleys, it is much easier to change the weight. Usually it is as simple as putting the weight stack pin in a different slot. You don’t have to work with weight plates or moving heavy pieces of equipment. These pulleys, however, limit the amount you can adjust the range of motion. Controlling the weight with free weights requires a higher level of skill as well as balance and coordination. It is recommended, especially with any power lifting, Olympic lifting, or heavy lifting in general, that a spotter is used to ensure proper form and reduce the risk of injury. Weight machines typically do not require the presence of a spotter because of their fixed range. Also, free weights typically require a greater metabolic cost, meaning you burn more calories.
The equipment you use in an exercise program really depends on what goal you are trying to accomplish. If you are unsure about what you should be using and/or doing, seek the help of a personal trainer or other fitness expert. A combination of both can be used to get the most out of your workouts. Just remember- safety first!
Blog post by Nikki Courtney.