February 26, 2010 — High-intensity resistance training plays an essential role in the prevention and rehabilitation of musculoskeletal injuries and disorders. Although resistance exercises with heavy weights yield high levels of muscle activation, the efficacy of more user-friendly forms of exercise needed to be examined.
“We were interested in a study that would confirm that elastic resistance is as effective as isotonic resistance without the hassle of dumbbells,” stated Phil Page PhD, PT, ATC, Director of Research and Education for Thera-Band Academy. “The convenience and accessibility of elastic bands and tubing can be very beneficial for patients continuing their exercises at home.”
Lars L. Andersen, PhD, and Mette K. Zebis, PhD, researchers with the National Research Centre for the Working Environment in Copenhagen, Denmark, completed a recent research study to investigate muscle activation and perceived loading during upper-extremity resistance exercises with dumbbells compared to elastic tubing.
The findings of this study were published online ahead of print on Feb. 4, 2010, by the American Physical Therapy Association at www.ptjournal.apta.org, the Web site of the Association’s journal, Physical Therapy (PTJ).
The article can be accessed at http://ptjournal.apta.org/future/90.4.dtl and will be published in print in the April 2010 issue.
The study involved 16 healthy female workers, aged 26–55 years, working in primarily sedentary jobs, i.e., office workers and lab technicians. Testing was performed on all 16 participants with both elastic tubing and dumbbells.
Thera-Band elastic tubing of different resistances (red, green, blue, black and silver) and standard iron dumbbells were the exercise equipment chosen for the study, along with three common rehabilitation exercises; one with a large range of motion (shoulder lateral raise), one with a small range of motion (wrist extension), and one involving joint rotation (external rotation).
Electromyographic (EMG) activity was measured in 5 selected muscles during the exercises, and the order of exercises and loadings was randomized for each participant. Electromyographic amplitude was normalized to the absolute maximum EMG amplitude obtained during testing. Immediately after each set of exercise, the Borg CR10 scale was used to rate perceived loading during the exercise.
The study showed resistance exercise with dumbbells as well as elastic tubing increased EMG amplitude and perceived loading with increasing resistance. The normalized EMG activity of the five muscles was not significantly different between dumbbells (59 percent to 87 percent) and elastic tubing (64 percent to 86 percent). Perceived loading using the Borg CR10 scale was moderately to very strongly related to normalized EMG activity (r=.59–.92).
“Comparably high levels of muscle activation were obtained during resistance exercises with dumbbells and elastic tubing,” continued Andersen, “This indicates that therapists can choose either type in clinical practice, allowing them to customize rehabilitation programs.”
The Thera-Band Academy provided the Thera-Band Exercise Tubing used in the study, but did not fund the study.
Source: Thera-Band, www.thera-band.com
