STRENGTH IS NOT RELATED TO MOVING QUICKLY IN ANY PRACTICAL WAY
Gardner, L. M., Brown, L. E., Coburn, J., Zinder, S. M., Kelly, S. B., & Nguyen, D. (2007). The relationship between strength and explosiveness. ACSM Annual Meeting New Orleans, Presentation Number, 1794.
The purpose of this study was to evaluate the relationship between strength and the ability to move quickly and produce force quickly. Peak torque, time to peak torque, rate of velocity development, and rate of force development during knee extension were measured. The correlation between isokinetic and isometric actions when examining torque, torque production, and movement speed was determined also. University students (N = 37) performed three maximal knee extension repetitions on an isokinetic dynamometer at both 0 and 180 deg/s.
There was virtually no relationship between isokinetic peak torque and time to peak torque or isometric peak torque and time to peak torque. Isokinetic peak torque and rate of velocity development demonstrated a significant but moderate relationship (r = .63). Isokinetic time to peak torque and rate of force development were found to have a significant weak negative relationship at r = -.37. No relationship was found between isometric time to peak torque and isokinetic rate of force development (r = -.20). Finally, isokinetic rate of force development and isometric rate of force development exhibited a weak significant relationship of r = .49.
Implication. There is no practical relationship between force and the ability to produce force quickly. Moving quickly and producing force quickly may be related only to a small degree. The current emphasis on improving strength to improve movement speed should not yield much, if any change because the two capacities have so little in common.
[Other methods of improving speed of movement should be sought because strength training will not influence that capacity in any significant way.]