Some questions about serves

[cloudtoo]

Hello everyone,

I joined TennisPlay this month and after reading the serve analysis i have some questions to ask Mr.Yandell, but if anyone else can answer my questions, it would be great, too.

In Mr.Yandell's Roddick's serve analysis, he mentions that "If you look at how high Andy gets in the air, and how far he hands inside the court, he's at the top or near the top in both dimensions compared to the other top servers." However, he also states in Federer's serve analysis: "The leg drive off this front foot is very powerful," " It is significantly more (air) than Roddick or Pete". Therefore I wonder which of them two has better leg drive?

Also, in Mr.Yandell's research, he found that Sampras has about 35% topspin due to his axis of spin. Is that on Sampras' first or second serve? I am assuming it is his first serve. If so, then does he change his axis of spin on the second serve? or simply just add more spin and the axis remains?

I have an impression about Federer and Roddick tossing more to the left on their second serves, is that true? If so, then they must have changed their axis of spin on their second serves..?

Thank you all in advance for the answers!!

[johnyandell]

Great questions.

Not sure I really know who has more leg drive or air...but it may be Roddick, Federer, and Pete in that order.

But I am not sure that matters when it comes to technique. Andy has that huge high leg kick back and bends over at the waist. Federer, as the current article shows lands more on balance with less kick back.

In everyway, his serve in my opinion is a far better model for most players--that's why I chose him for the new serve series that started last month with part 2 in the current issue.

And yes! The toss for Fed and Pete (and Andy and everybody) is more to the left for the second serve. The spin is increased, and the axis is steeper, though I can't give you an exact break out on the topspin percentage.