International Journal of Exercise Science 9(5): 635-645, 2016. Muscle contractile properties have previously been distinguished by fiber typing muscle samples obtained from needle biopsy; however due to conflicting evidence regarding sampling bias and the related need for multiple biopsies, it is not certain if these results are a reliable reflection of whole muscle fiber type expression. Inter-correlations between laboratory and field-based measures of muscle contractile power were used to determine which assessments best discriminate between participants of varying sprint performance, and indirectly reveal potential for power vs. endurance exercise performance. Healthy active male (n=32) and female (n=17) participants were recruited from the Central West region of New South Wales. Isometric rate of force development (RFD) and isokinetic torque were assessed at different velocities. A counter movement jump (CMJ) test was implemented to assess concentric and eccentric RFD. A modified Wingate test was used to assess peak power expressed as Watts using a stationary start to the onset of decreased cadence. A 20m sprint was used as a field-based measurement of exercise performance, recording split times at 2m, 10m and 20m, and interval times from 2-10m, 2-20m, and 10-20m. Over 85% (r2=0.851) of 10-20m sprint running performance variance was significantly accounted for by a multiple regression model consisting of peak Watts per kilogram body mass during the modified Wingate (pkWkg), sex, and peak concentric rate of force development (pkcRFDkg). Results indicate a highly significant and predictive relationship between performance measures assessed by the modified Wingate test and sprint running performance in both males and females. Laboratory power tests alone seem sensitive enough to ascertain suitability for power vs. endurance performance potential