Ignore the Safety Myth, Free Weights Compare Favorably to Machines

On my first day as a personal trainer at a fitness club, I had an appointment with a twelve year old girl. In order to use the facility, minors first had to go through a personal training session. I asked my boss if he had any advice or precautions for youths. He told me to just stay with the basics and, oh yeah, just keep them on machines because they are safer. I ignored my boss. Provided an athlete is smart, and does not attempt to lift too much weight, weightlifting is safe. In fact, youth fitness expert Brian Grasso believes the myth that machines are safer than free weights “is simply a dogmatic mindset and not founded on any scientific or functional principle. It is a classic case of blaming the activity rather than the execution. In fact having young athletes train on machines for strength development can actually lead to injuries.” Currently, “functional training” is all the rage. Personal trainers use wobble boards, Bosu balls, stability balls, etc because it makes the exercise “more functional.” In reality, “functional training trains movements not muscles! In other words functional training prepares and conditions you by practicing movements that are toward your desired goals,” (Spida Hunter). The basic problem with machines is they isolate the muscle by using seats and back rests to support the body. However, during an athletic movement, or even in activities of daily living, one never isolates a muscle in this manner. How many sport movements involve sitting in a chair? Every movement or action requires an agonist (prime mover), antagonist, synergists and neutralizers working together to stabilize and support the body in its effort to perform the movement. “By isolating certain muscle groups via machine-based training, you are eliminating the body’s natural capacity to provide both mobility and stability in an interrelated manner. This can easily limit a young athlete’s ability to effectively produce force on the field of play while at the same time providing stability in other crucial areas of the body. By disturbing this innate mobility/stability balance, you are decreasing the ability of the body to protect itself during dynamic and unscripted movements experienced during a sporting event…increasing the risk of injury on the field of play,” (Grasso). Or, as Spida Hunter says, “Do you compete while seated in a machine that’s bolted to the floor?” The twelve year old girl played basketball, volleyball and track. Adolescent female soccer, basketball and volleyball players are at a great risk of ACL injury, two to eight times more likely than a male peer. The most important aspect of her training, to me, was teaching proper movement patterns in order to prevent an ACL injury; any performance increases were an added bonus. Using a machine would not teach the movement patterns necessary to decelerate the body to make a cut or land from a jump, the two areas where most ACL tears occur. While a leg extension machine and a leg curl machine can develop quadriceps and hamstring strength, muscles involved in decelerating movements, there is very little transfer between the weightlifting machines and sport activities. A squat, however, teaches the proper movement pattern while increasing strength throughout the legs. Many young girls do not squat properly; in fact, the inability to squat correctly prevents correct landing from a jump and places excessive stress on the ACL, one reason females tend to tear their ACL’s at a disproportionate rate. By using just the girl’s body weight, the squat increases leg strength and improved neuromuscular efficiency, which transfers directly onto the court. A second reason machines fail is they prevent the body from supporting itself during exercises. Many personal trainers hesitate to use an overhead lift with young athletes, using an overhead shoulder press instead. However, “seated vertical pressing machines place a great deal of stress on the lumbar spine-more so than standing vertical pressing exercises. In fact, many young athletes, in an attempt to press as much weight as possible, will actively hyperextend the lower lumbar in order to gain extra leverage,” (Grasso). When doing a standing overhead press, the body stabilizes itself rather than the chair acting as the stabilizer. While this does place more stress on the body, it is this stress which helps to build greater overall strength. Without an impetus, the stabilizing muscles fail to develop at the same rate as the prime movers involved in the lift. When one lifts a box overhead, he risks injury, despite his heavy training, because his core muscles are untrained and unable to support the weight. Every athletic movement uses multiple muscles in multiple planes (transverse, frontal and sagital). A machine works one muscle in one plane (sagital). Therefore, training does not transfer from the machine to the field or court. For this reason, free weights are better for performance training, as they are more functional and build overall strength, including stabilizers in the core which are ignored by machine exercises.