Brian Grasso, CEO for the International Youth Conditioning Association, travels extensively throughout the world as a guest lecturer on the topic of youth athletic development and fitness. You can find dozens of free articles, sample programs and resources on his Web site, www.DevelopingAthletics.com, or at www.IYCA.org.
Whenever I come into contact with a coach or trainer who preaches the virtues of machine-based strength training for young athletes and clients, I often hear the same argument — machines are safer for kids because they eliminate the dangerous aspects of traditional free weight training. This is simply a dogmatic mindset and not founded on any scientific or functional principles. It is a classic case of blaming the exercise or activity rather than the execution. In fact, having young athletes train on machines for strength development can actually lead to injuries and a whole host of other concerning factors.
All sports and movements are dynamic and require a great deal of systemic strength and stability to perform. Moreover, the strength/stability interplay needed to perform virtually any sporting activity is based on the body (or its parts) working as a unit, the way nature intended. By isolating certain muscle groups via machine-based training, you eliminate the body's natural capacity to provide both mobility and stability in an interrelated manner. This can essentially 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 the dynamic and unscripted movements experienced during a sporting event.
Coaches and trainers who incorporate machine-based training into the routines of young athletes as a way to promote weight room safety are, in essence, increasing the risk of injury on the field of play. One of the primary goals of a sound strength and conditioning program is to prevent injuries during a sporting event or season. Coaches and trainers who insist on using machines for training purposes are then suggesting that trading sport safety for weight room safety is somehow a good deal.
Here's a look at some of the finer points of machine training:
Functionality in both sport and life is based on healthy movement, certainly not isolation. In that, proprioceptive neuromuscular facilitation (PNF) plays a vital role. Often noted as a type of stretching exercise, PNF is actually a diverse and intensive concept that involves movement-based stimulus following spiral or diagonal motions (to reflect that oblique nature of most muscle orientations), with the primary goal of developing motor learning through precise movements.
Having said that, machine-based strength training, with its isolated format, is simply not functionally similar to innate patterns of motion that a young athlete would use on the field of play and is quite disruptive to basic physiological factors of movement, such as normal timing (which refers to the naturally occurring timing of the phases of movement during a given motion).
Even with cardiovascular training, it is less than optimally productive for young athletes to use the stationary bikes and treadmills found in most health clubs. Possessing optimal speed, agility or any other reactive locomotor ability is based largely on hip and trunk flexibility and strength. Both cycling and treadmill running serve to limit hip range of motion and can cause decreases in the dynamic flexibility within the hip complex. Young athletes are better served to incorporate rigorous sprinting or movement-based interval training (such as Fartlek) into their training routines.
For strength training to be effective, all you have to understand is that force production (the action of producing strength) must come in the form of systemic (whole) body involvement and must be based on macro-movements that kids naturally perform and understand.
A 'cheat sheet' to designing effective strength training programs for kids, therefore, is to be sure your exercises involve the following categories:
Nothing could be more simple.