▁width . ▁In ▁a ▁tournament , ▁the ▁boat ▁spe eds ▁up ▁or ▁the ▁ro pe ▁short ens ▁until ▁the ▁sk ier ▁fails ▁to ▁complete ▁the ▁sl alom ▁course ▁by ▁falling ▁or ▁not ▁getting ▁around ▁a ▁bu oy . ▁ ▁A ▁sk ier ' s ▁score ▁is ▁based ▁upon ▁the ▁number ▁of ▁successful ▁bu o ys ▁cleared , ▁the ▁speed ▁of ▁the ▁boat , ▁and ▁the ▁length ▁of ▁the ▁ro pe . ▁In ▁a ▁tournament , ▁ski ers ▁choose ▁the ▁starting ▁boat ▁speed ▁and ▁ro pe ▁length ▁( with ▁a ▁maximum ▁length ▁of ▁). ▁Professional ▁water ▁ski ers ▁will ▁typically ▁start ▁at ▁the ▁max ▁speed ▁of ▁ ▁with ▁a ▁ro pe ▁that ▁has ▁already ▁been ▁short ened ▁to ▁. ▁The ▁sk ier ▁with ▁the ▁most ▁bu o ys ▁wins ▁the ▁competition . ▁ ▁The ▁turn ▁bu o ys ▁are ▁position ed ▁ ▁away ▁from ▁the ▁center ▁of ▁the ▁sl alom ▁course . ▁As ▁the ▁ro pe ▁is ▁short ened ▁beyond ▁that , ▁the ▁ski ers ▁are ▁required ▁to ▁use ▁the ▁momentum ▁generated ▁through ▁their ▁turns ▁to ▁swing ▁up ▁on ▁the ▁side ▁of ▁the ▁boat ▁and ▁reach ▁out ▁in ▁order ▁to ▁get ▁their ▁ski ▁around ▁the ▁next ▁bu oy . ▁At ▁these ▁ro pe ▁lengths , ▁the ▁sk ier ' s ▁body ▁is ▁experien cing ▁inten se ▁is ometric ▁contra ctions ▁and ▁extreme ▁upper ▁body ▁tor que ▁with ▁loads ▁of ▁up ▁to ▁ 6 0 0   kg ▁as ▁they ▁begin ▁acceler ating ▁after ▁round ing ▁a ▁turn ▁bu oy . ▁Their ▁top ▁spe eds