According to a article published in La Gazzetta dello Sport’s weekly magazine SportWeek, the worlds hardest hitter for women is Yanelis Santos from Cuba with a 103 km/h spike.
Full article here: http://www.fivb.org/viewHeadlines.asp?No=34473&Language=en
Personally, I guess there is players that hit harder than Santos in attack. What do you think, who hits the ball with most power? Share your thoughts!