▁Water ▁ski ers ▁can ▁use ▁two ▁sk is ▁( one ▁on ▁each ▁foot , ▁also ▁called ▁" com bo ▁ski ing ") ▁or ▁one ▁ski ▁( domin ant ▁foot ▁in ▁front ▁of ▁the ▁other ▁foot , ▁also ▁called ▁" sl alom ▁ski ing "). ▁Gener ally ▁the ▁heav ier ▁the ▁person , ▁the ▁bigger ▁the ▁sk is ▁will ▁be . ▁L ength ▁will ▁also ▁vary ▁based ▁on ▁the ▁type ▁of ▁water ▁ski ing ▁being ▁performed ; ▁jump ▁sk is , ▁for ▁example , ▁are ▁longer ▁than ▁sk is ▁used ▁in ▁regular ▁straight - line ▁recre ational ▁ski ing ▁or ▁compet itive ▁sl alom ▁and ▁trick ▁ski ing . ▁A ▁trick ▁ski ▁is ▁around ▁ 4 0 ▁inches ▁long ▁and ▁wider ▁than ▁com bo ▁sk is . ▁Again ▁the ▁sk ier ▁r ides ▁it ▁with ▁his ▁or ▁her ▁dominant ▁foot ▁in ▁front . ▁It ▁has ▁no ▁fins ▁which ▁allows ▁for ▁sp ins ▁to ▁be ▁performed . ▁ ▁Bo at ▁ ▁Compet ition ▁ski ing ▁uses ▁specifically ▁designed ▁to w bo ats . ▁Most ▁to w bo ats ▁have ▁a ▁very ▁small ▁h ull ▁and ▁a ▁flat ▁bottom ▁to ▁minim ize ▁w ake . ▁A ▁true ▁tournament ▁ski ▁boat ▁will ▁have ▁a ▁direct ▁drive ▁motor ▁sh aft ▁that ▁cent ers ▁the ▁weight ▁in ▁the ▁boat ▁for ▁an ▁optimal ▁w ake ▁shape . ▁However , ▁some ▁recre ational ▁ski ▁boats ▁will ▁have ▁the ▁motor ▁placed ▁in ▁the ▁back ▁of ▁the ▁boat ▁( v - drive ), ▁which ▁creates ▁a ▁bigger ▁w ake . ▁Perm itted ▁to