Even with seemingly simple strength exercises like bicep curls or bent-over tricep kickbacks, it's very easy to perform them with poor form.
Like with bicep curls, many people will swing their entire arm and/or body to create enough momentum to lift the weight. One way to avoid this, and more thoroughly and effectively work the muscle group, is to keep the upper arm pinned to your side with your elbow acting as a fulcrum (while using a lighter weight).
By doing this you ensure that you don’t swing the shoulder and upper arm (which is pinned against your side so it doesn’t move in this fashion) to move the weight. In fact, drop some weight and try this out and you will realize that you get an amazingly effective workout because you are solely working the muscle group you intended to target.
To prevent injury and make your workouts more effective, make sure to learn proper form before performing any exercise.
Josh Anderson is an AFAA Certified Personal Fitness Trainer and the CEO of Always Active Athletics.