Healthy Back Tips

March 2008

Weight Machine Exercise vs. Functional Training

For many people a workout means going to the gym to use machines that offer weight resistance in order to get stronger. The intent is to utilize various machines to build strength in specific muscles or muscle groups by selective muscle isolation. Most gyms have personal trainers or physical therapists available to help instruct how each machine is to be set up for safety purposes as well as to make exercise recommendations. Machine resistive exercises will improve muscle strength within 4-6 weeks providing correct form is used, resistance is properly selected to challenge your muscular system and workouts are performed consistently (2-4x/week).

One question to consider when involved in a weight resistive program to improve muscle strength is whether the increase in strength of a specific muscle by using machines will actually apply to the physical activity you wish to accomplish. For example, if your goal is to be able to transfer from sitting to standing without having to push up with your arms a leg extension machine (Fig. 1) may help to build quadricep strength, but the increase in quadricep strength may not necessarily enable a successful sit to stand transfer since the two actions are different. The leg extension machine trains the quadricep muscle to raise the lower leg against resistance from a sitting position which is an activity very different from a sit to stand transfer activity where the quadricep functions to extend the knees with the feet on the floor. 

Figure 1

A functional training approach may involve a sit to stand exercise, but initially performed from a chair or seat that is higher than a normal chair height in order for successful performance. Another alternative for sit to stand functional exercise involves placing several pillows on a chair seat of standard height (Figs. 2A, 2B). In this scenario, all the muscles in the lower extremity are recruited and strengthened in the actual functional activity thereby enabling the quadriceps as well as hip extensors to not only get stronger, but to learn the most effective way to transition from sit to stand.

Figure 2a

Figure 2b

In a similar manner, if an athlete’s goal is to improve lateral movement performance for sport activity, strengthening the lateral hip muscles using the hip abduction machine may help. The hip abduction machine exercise (Fig. 3) which is performed from a sitting position, however, does not replicate lateral movement performed in sports. Therefore, strength gains achieved with a hip abduction machine may not necessarily result in improving lateral mobility for the athlete. On the other hand, a functional training exercise such as lateral lunges or side steps performed with resistance (Fig. 4) challenges the entire body in a motor task that actually relates to what is required for improving sport performance for lateral mobility. Neural reflex pathways to the targeted muscles for lateral movement are facilitated, muscular actions learn how to sequence efficiently for the task and muscles are strengthened in the action required for successful lateral movements.

Figure 3

Figure 4

Function of the human body is somewhat analogous to the music produced by an orchestra. If you want to hear a violin solo find the correct weight resistive machine for the muscle you want to train and go to town. If your objective, however, is to achieve optimal function for a specific motion task you might consider inviting the full orchestra to play. The sound produced is typically more powerful and the effect may have greater meaning.

If you are interested in a functional training exercise program to (1) improve your body mechanics and lessen risk for injury (2) learn a more efficient way to perform a motor task (3) optimize your sport performance athletic skills or (4) improve your balance so as to reduce potential for falls give us a call to schedule an appointment for an evaluation.

For more information specific to your condition, contact the Atlanta Back Clinic, or call us at 770-491-6004 to set up an appointment with a physical therapist.

References for Figs. 1 and 3 – Strength Training Anatomy, Frederick Delavier, Human Kinetics, 2001