A comparison of the kinematics, kinetics and muscle activity between pneumatic and free weight resistance.
Pneumatic devices provide a resistance comprising minimal mass, possibly affording greater movement velocities, compared to free weight, while reducing the influence of momentum. Thirty men completed three testing sessions [free weight (FW), ballistic (BALL) and pneumatic (P)] each consisting of a one repetition maximum (1RM) and six sets (15, 30, 45, 60, 75 and 90% 1RM) of four explosive repetitions of a bench press. Dependent variables were expressed as mean and as a percentage of the concentric displacement. Significant differences (P < 0.05) were evaluated using two way repeated measures ANOVAs with Holm-Sidak post hoc comparisons. On average, the mean and peak P velocity were 36.5 and 28.3% higher than FW, and 22.9 and 19.1% higher than the BALL movements. The FW and BALL peak force were both significantly higher than the P (26.3 and 22.7% for FW and BALL, respectively). BALL mean power output was significantly higher than the FW and P at loads of 15 and 30% 1RM; however, between loads of 60-90% 1RM the highest mean power was produced with a P resistance. A 15% 1RM load maximized the peak power for each condition and no significant differences were found between the P and BALL. For loads of 45-90% 1RM the force, power and muscle activity were higher during the last 10-20% of the concentric displacement when subjects employed the P resistance. In summary, pneumatic resistance may offer specific advantages over loads comprising only mass (FW and BALL), although not without its own limitations.
Frost
David Michael
DM
Department of Kinesiology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada. d3frost@uwaterloo.ca
Cronin
John Barry
JB
Newton
Robert Usher
RU
D000328:Adult; D001696:Biomechanical Phenomena; D004576:Electromyography; D015444:Exercise / Q000502:physiology*; D006801:Humans; D007700:Kinetics; D008297:Male; D009068:Movement / Q000502:physiology; D009119:Muscle Contraction / Q000502:physiology*; D053580:Muscle Strength / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology*; D014891:Weight Lifting / Q000502:physiology*