Table 1 The validity of the Chronojump System, compared with the Biopac System, and the linear encoder (criterion measure) distance and velocity calculations (n=10). Parameter Paired Differences 95% confidence interval of mean differences M SD SEM Lower Upper t value df Significance Distance 40kg -.007 .014 .001 -.010 -.004 -4.83 86 .000 Distance 50kg .015 .011 .001 .012 .017 11.30 77 .000 Distance 60kg .031 .013 .001 .028 .035 21.00 75 .000 Velocity 40kg -.012 .024 .002 -.017 -.007 -4.76 86 .000 Velocity 50kg .027 .020 .002 .022 .031 11.81 77 .000 Velocity 60kg .056 .019 .002 .051 .060 24.81 75 .000 Global Distance .012 .020 .001 .009 .014 9.19 242 .000 Global Velocity .022 .035 .002 .017 .026 9.66 242 .000