How to make sense of the new WTA Power Index

In this post, I’ll take a short break from our ongoing discussion about how to improve your court movement to discuss an interesting speed-related event from the tennis world.

The event I wanted to mention was the launch of the “WTA Power Index” earlier this month at the final Acura Classic in San Diego. The point of the WTA Power Index is marketing—i.e. to give the fans a greater appreciation of the performance capabilities of the top female pros by highlighting how powerfully they strike the ball.

According to the official WTA Tour press release (8/8/07) explaining the Power Index:

“(I)t’s a great way (The Power Index) to recognize the extraordinary talent, athleticism, and sheer power of our top players… Other leading professional sports have introduced new methods to measure and compare the performance of their players to provide another level of insight to fans. The Power Index affords that same opportunity for women’s tennis.”

The WTA Power Index is calculated by taking the average speed of a player’s first serve, second serve, forehand, backhand, and overhead measured using the Hawk-Eye line-calling systems that are installed on all of the center courts of all the US Open Series tournaments.

And thus far, the most powerful player on the WTA Tour after the first three weeks of the Power Index is: (fanfare, please) Yaroslava Shvedova of Russia with an index of 102.9 MPH. Future Hall-of-Famer Venus Williams is second with an index of 98.8 MPH. Other notable (i.e. recognizable) names among the Top 10 players on the cumulative Power Index stats are Nadia Petrova (#4 at 97.4 MPH) and Elena Dementieva (#5 at 95.8 MPH).

Yaroslava Shvedova is the most powerful player on the WTA Tour? Hmmm… Shvedova isn't exactly a household name in women's tennis. She's not even one of the higher-ranked WTA players sitting currently at #74 in the official WTA Tour singles rankings.

In fact, there isn’t much of a correlation between the Power Index rankings and the actual WTA rankings. Look, the most powerful player in the short history of the Power Index, Shvedova, is currently ranked #74, and upon closer examination, 7 of the current Top 10 players on the Power Index are ranked outside the Top 25 of the actual player rankings.

I wonder how the WTA Tour is going to explain the inverse correlation between power performance and ranking performance?

Regardless of the Tour’s spin on the issue, I think that it shouldn’t surprise anyone that pure power isn’t necessarily a guarantee of match wins, especially among the women. Especially when you begin to notice that many of the biggest hitters among the WTA pros are not very adept movers on the court.

If you’ve been following this blog on a regular basis, you should understand by this point that slow court movement combined with big hitting is really a recipe for disaster from a high-performance perspective. Attempting to hit “big” with slow feet (you should also realize that there are many in the (pro) coaching establishment who preach that powerful stroking compensates for being a slow mover) is the classic, proven formula for maximizing unforced errors and makes it even more difficult to win any tennis match, especially one at the pro level.

Another detail to consider in explaining the disparity in the Power Index and actual player rankings is the fact that the women achieve those shot velocities with using far less (top-)spin that is essential to control such high-velocity strokes during play.

What this means is that while some WTA players may generate high shot speeds, they do so with far less control than their male counterparts on the ATP Tour. With far less spin on their shots (as in 50 to 70 percent less spin compared with the men on average) and therefore, far less control over their shots, the players who are top-ranked on the Power Index are, not surprisingly, also those same players with a proven reputation for generating large numbers of unforced errors during their matches.

Any tennis player who commits too many errors of the unforced variety is going to have a tougher time winning matches with any consistency. So when you begin to look at things more closely, it’s no real surprise that there isn’t a strong correlation between the Power Index rankings and the actual WTA rankings. The big hitters make way more errors during play and have a harder time winning matches consistently, so their rankings are lower.

I would be very interested to know what would happen if the WTA Tour could somehow introduce a “spin factor” into the Power Index—my prediction is that when spin production is part of the formula, the Power Index rankings will much more closely resemble the player rankings. And, yes, if you are wondering, with Hawk-Eye technology, it is possible to measure the spin rates of each shot struck during play.

Finally, I’ll make one final comment about the potential impact of the WTA Power Index… That is to say that tennis may be the one professional sport where the fans may achieve a greater insight into the quantitative aspects of the performance of their favorite players before the professional coaches who are paid the big bucks to train and prepare them.

Pro tennis coaches, by and large, do not pay much, if any attention to the quantitative aspects of the sport they are considered experts at. Sure they can recognize unusual physical ability—“talent”—when they see it, but they have almost absolutely zero idea about the quantitative details of the talent they observe.

Pro coaches generally do not know the speeds and spin rates or running times of their players. They consider these parameters to be unnecessary details mainly because they generally believe that the success in pro tennis is determined primarily, if not exclusively, by intangible factors such as “confidence” and mental toughness and motivation to perform hard work. They even believe that these intangibles can overcome the great majority of physical or technical shortcomings that a given player may have.

These beliefs are mainly based in the personal experiences of the great majority of coaches at the pro level, who were often former professional players themselves (with varying degrees of success). In the days when they were active players (typically in the 1970s and early 1980s), it was true that the psychological intangibles were paramount in determining a player’s ability to succeed on the tour because there was very little physical or technical separation between the pro players of that day and age.

Today, physical ability plays a far greater role in determining a player’s ability to succeed at the pro level, although the establishment continues to recite their deeply entrenched perception that the intangibles remain the most critical determinant of pro success. Today, racket speed and foot speed in particular create separation between the true pro contenders from the rest of those players toiling in the purgatory known as the Challenger and Futures circuits.

No matter how mentally tough and focused a prospective pro player may be, if he can’t consistently hit first serves over 125 MPH or can’t put a 130 MPH serve consistently back into play or retrieve a 95 MPH groundstroke slammed into the corners, no amount of mental skill and savvy can compensate for a lack of physical capacity.

This is the new reality of professional tennis…

Pro tennis has become essentially identical to other professional sports in that you must possess ultimate physical talent to succeed at the highest possible levels of the sport. Intangibles such as confidence and motivation remain as key factors in maximizing one’s competitive potential, but such intangibles can no longer compensate for a player’s physical shortcomings and athletic limitations (see Hingis, Martina).

TTFN!

Court Movement 102

Today’s post is the continuation of the post titled “Court Movement 101” where I began to discuss the fundamentals of efficient, effective court movement. The take-home message from that post was to help you understand how proper court movement “feels”—it feels as if you are constantly accelerating and decelerating in response to your opponent’s shots rather than moving around at a single, uniform speed.

The whole point of that moving that way is to enable you to consistently find a solid hitting stance from which to execute your strokes, regardless of whether it’s a groundstroke or overhead (the volley is a different animal entirely, a stroke you need to hit while moving)—ideally, before the ball bounces on your side of the court.

Let’s expand on this concept here…

1. WIN THE RACE WITH THE BALL

The message I tell my own players about their court movement is that what they are really doing is “racing” with the incoming ball… Their goal is to win that race with the ball so that can achieve their optimal hitting stance before the ball bounces on their side, such that they can execute their own return with maximum power and control.

If you don’t win that race and fail to achieve a solid hitting stance for your groundstroke, volley, or overhead, you will compromise almost every element of your return— power, control and consistency. When you move poorly and lose that “race” with the ball, the chances of hitting a poor return, or missing the court outright grows almost exponentially. A smart, experienced competitive player understands that you have to dial down the precision or the power (or both) of your return when you’re moving poorly because the chance of making stroking error multiplies exponentially when you’re late to the ball, can’t find a solid stance, rush to make contact, etc.

A savvy competitor knows that when their movement is slow for whatever reason, they need to become way more conservative with their power and placement of their own strokes and focus on both 1) improving their movement and 2) keeping the ball in play rather than “going for their (big) shots”. The not-so-savvy player won’t make those necessary adjustments to their shots and their gamestyle rapidly descending to the level of what I like to call “sprinkler tennis”, where a player appears to be randomly spraying their returns everywhere but inside the lines of the court.

2. DEFINING THE ATTRIBUTES OF A SOLID HITTING STANCE

So the immediate benefit of proper court movement is the consistent ability to create a solid hitting stance. So what is a solid hitting stance, then?

First, let’s consider the attributes of a solid hitting stance for a groundstroke. In general, there are three main attributes of a solid hitting stance:

1) The feet are placed well beyond shoulder-width. A solid hitting stance is a wide stance.

2) Your knees comfortably flexed (or bent sufficiently to get down to the contact height of your stroke on low returns.

3) Your back is relatively straight and is tilted slightly forward from the hips.

4) Given today’s rotary groundstroking movements (emphasizing fast hip and shoulder rotation), you need to find either an open or square stance with your feet.

The closed stance, while still used by players during live matchplay, not only inhibits the full range of hip and shoulder rotation necessary to properly execute modern rotary groundstrokes (I will get more into this rotary concept in later posts), but will cause undue stress and strain on the hip and knee joints in the long term that may lead to chronic and possibly debilitating injuries (i.e. chronic hip injuries in former ATP #1s Kuerten and Norman).

When you find a solid hitting stance that incorporates these four fundamental characteristics, you will maximize your potential to make a long, fast, powerful and balanced stroke. The width of your stance will enable you to maintain your balance easily despite the great forces you will generate with your hip and shoulder rotation, as well as enable you to transfer the force you generate more efficiently into contact.

Essentially, your hitting stance should be very similar to your ready position after your split-step… Where, you need to get into an “acceleration” posture (this is the whole purpose of assuming the classically-defined “athletic stance”, as it enables the body to accelerate most efficiently in any direction) that allows you to maximize your ability to explosively accelerate in any direction (i.e. overall body angle of 45 degrees relative to the ground). This same posture also allows you to rapidly accelerate the body segments (upper and lower) required to properly execute the modern rotary groundstrokes.

Narrow hitting stances also tend promote shorter strokes as it’s harder for the body to maintain its balance while making a long, fast stroking motion. Players who use narrow stance typically have trouble controlling the depth of the strokes, and have a strong tendency to hit the ball very short rather than deep.

This concept is easy to demonstrate… Assume a narrow stance, and try to make a long, fast stroke with a full, forward weight transfer... Trouble maintaining your balance?

Now try widening your stance and make another long, fast stroke. Didn’t lose your balance this time, right? What’s the result on-court? Well, when you widen your stance, you should find that hitting with great, consistent depth becomes a whole lot easier to do mainly because the extra width of your stance encourages the full, fast, long stroke required to generate consistent depth.

3. HEEL FIRST—USING THE "LONG STEP" TO FIND THE PROPER HITTING STANCE

OK, what’s the easiest way to find the correct hitting stance when the game’s in motion? It’s quite simple… Make your last step on your approach to your opponent’s return an extra-long step. Typically, the final two to three steps as you near the exact point where you want to set up to the oncoming return should be smaller, choppy steps to help you decelerate smoothly from your initial (often longer) explosive move toward the oncoming return. But, small, choppy steps typically encourage finding a narrow stance.

So, instead, you should consciously make that final step, what the Germans refer to as a “long step” leading with your back foot, to encourage, if not ensure that you “form” a wide stance with your feet well outside shoulder-width.

Another important detail to consider when making that “long step”, is to make sure that you land with your heel first, then transfer your weight onto the ball of your foot. That’s right, I said land with your heel first when making the “long step”.

For many of you that is a contradiction in terms, as you should know that to run at maximum speed, you need to land on the balls of your feet. Indeed, that is what you need to do in the first two phases of your movement toward the oncoming return, you need to move explosively and this absolutely requires that you make contact with the court with the balls of your feet.

However, when you need to establish your hitting stance, the final part of the three-part court movement sequence (actually, it’s four parts, including the recovery movement after finishing your follow-through), landing on the ball of the foot during your “long step” is not the best method.

Remember, finding your optimal hitting stance requires that you stop and set your feet, and it is far more efficient to stop, and, more importantly, maintain your balance while stopping, by landing heel first. Landing heel-first enables you to “roll” forward onto the ball of your foot—if necessary—to dissipate any remaining movement forces. Landing heel-first also enables you to flatten your feet completely against the ground to promote an efficient forward weight transfer during your stroke.

Trying to stop and form your hitting stance by landing on the forefoot rather than on the heel will cause you to lose your balance as there is no way to dissipate any movement forces other than to lose your balance momentarily (the force(s) essentially has “nowhere to go” when you land on the forefoot) and typically causes you to make another extra step to regain your balance. Landing on the ball of the foot to make the final, “long step” is an inefficient and potentially risky method (What if your forefoot gets “stuck” on the court surface? All that sudden force then goes into stretching, shearing, and tearing your ankle tendons and ligaments… Not a good thought!).

So, what’s the take home from this post?

After you win the “race with the ball”, use the long step to “find” a proper hitting stance.

TTFN!