Perceived submaximal force production in young adult males and females

Purpose: This study used psychophysical methods to quantify subjects' error s during submaximal muscular force production. Methods: A sample of young a dult (aged 23 +/- 3 yr) females (N = 60, 62 +/- 14 kg) and males (N = 50, 7 2 +/- 13 kg) performed a chest press on a hydraulic dynamometer with which they were unfamiliar. In four consecutive presses with a 2-min rest interva l between each press, the subjects were asked to produce a force in the ord er of 25%, 50%, 75% of their maximal force, and a final maximal press. Pilo t data (N = 10) indicated good reliability (r(xx) > 0.80) for the protocol. Results: The rs between perceived force production and the desired product ion were 0.76 (P < 0.001) for males and 0.75 (P < 0.001) for females. The e xponent for the power function between the perceived and desired forces was 1.12 for males and 1.03 for females. The total error ranged from 2.82 kg m (males) to 1.22 kg m (females). The rs and the logarithmic matching of per ceived and desired force indicated a linear relationship that is consistent with Borg's range model, which has proposed that perceptual intensities of force for different people are approximately set equal at a subjective max imum. Conclusion: Many young healthy subjects can produce relative muscular forces with good accuracy. However, some subjects will provide very inaccu rate forces that might affect outcomes in rehabilitation or physical traini ng.