An Evaluation of a Strength Qualities Assessment Method for the Lower Body

ABSTRACT The purpose of this investigation was to evaluate an assessment method for the lower body and its ability to detect training induced changes in athletes. A repeated measures study design was used to assess reliability; in addition several longitudinal single subject case-studies are reported, justifying the sensitivity of the test to detect training induced changes. Inter-day reliability of the measures was assessed with repeated measures 48 h apart and the detection of training induced changes was evaluated by tracking athletes over a normal conditioning period which included resistance and sport specific training. Peak force for the isometric mid-thigh pull was 2879±613 N and 1988±412 N for the squat jump, resulting in a mean Dynamic Strength Deficit of 0.70±0.10. The coefficient of variation ranged from 2.01-3.19 % and intra-class correlation coefficients of 0.952-0.987 were observed. For athletes involved in lower-body maximal strength training, their pre and post measurements recorded changes in isometric mid-thigh pull peak force (215-362 N), and changes in the Dynamic Strength Deficit ratio (0.03-0.14) that exceeded the measures technical error. The Dynamic Strength Deficit ratio, is a reliable means of assessing an athlete‘s strength qualities, and comparisons of the force measures appear to be a valid means to detect training induced changes in athletes. Keywords

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