Saturday, December 1, 2012
Optimum Racquet Balance for Performance by travlerajm
Originally Posted by Circa 1762
I think you're misconstruing travlerajm's argument. Each person, the theory goes, has an ideal MgR/I, but this ideal MgR/I depends on things like arm length. Therefore, each person's ideal MgR/I is going to be slightly different. Travlerajm has looked at the specs of pro's rackets, and based on the assumption (I think) that pros are likely to have MgR/I's close to their ideal, found that the pros cluster around an MgR/I of 21.0 (although again, there are variations due to things like height). As a result, he's suggesting (travlerajm, correct me if I'm wrong) that you might want to start with your search for your ideal MgR/I around 21.0. He is not saying that your ideal will necessarily be 21.0.
Based on a series of blind tests - for example, setting up two rackets with the same weight and swingweight but different balance, leading to different MgR/I's - I've concluded that my ideal MgR/I is around 21.2. I'm shorter than the average pro (5'8"), so this isn't too surprising. And these were blind tests with the exact same racket model and on the same day, so I'm pretty sure the differences I felt were real. So basically, don't just set your racket up to MgR/I = 21.0 and call it a day. If you have two rackets, set one to 21.0 and one to 21.1, and see which you like better (you should feel a difference). Say you like the 21.1 racket better. Next, leave that one the same, but set the other one up to MgR/I = 21.2. If you still like the 21.1 racket, you can be pretty sure your ideal is around 21.1, and almost positive it's between 21.0 and 21.2. You can continue to do blind testing like this until you zero in on your ideal.
Response by travlerajm
Nicely summarized! This post might also be useful:
Originally Posted by ART ART
travlerajm: again nice to see you around here
But I have a question for you:
I have this setup(lead+silicone) in a Dunlop 300T:
- 353 grams
- 360 SW
- 33 mm BP
Wich give me:
MgR/I = 20,49
like you can see, my MR^2= 385 this is an optimal value. BUT my MgR/I = 20,49 -much lower than optimal value.
How about it?
It's my belief that the optimal MR^2 zone of ~385 arises due to circumstance, because those pros that have both high swingweight (>350) and optimized MgR/I value (~21.0) tend to have racquets with MR^2 of about 385.
There are many pros with high swingweight but suboptimal MgR/I value. And there are many pros with optimized MgR/I value but low (suboptimal) swingweight. In both cases, the MR^2 value tends be less than 380.
My opinion is that it is well worth it to tune your MgR/I value to your personal optimum for your body and your swing.
You have already accomplished Step 1: getting accurate measurements for a starting point.
Step 2 is to calculate how much weight should be placed on the handle to move the MgR/I value to ~21.0 (to get it close).
Step 3 is to make the modification.
Step 4 is to remeasure the specs and verify that you are close to 21.0.
Caution: You're not done yet, as the most important step still remains!
Step 5: Tuning the racquet on the court:
I recommend that you grab some extra lead tape and find a wall or racquetball court. You cannot tune the MgR/I value by hitting balls that you drop -- you need the balls to be coming at you with decent velocity in order to tune the angular velocity of your stroke, so a wall is perfect for that.
The key to tuning your forehand is to unlearn your developed habit of compensating for racquet misalignment at impact by applying force with the wrist. You need to learn how to swing the racquet fluidly with a completely relaxed wrist.
A good analogy is when you go to the optometrist for the first time in your life to get glasses for near-sightedness. All of your life, you've been squinting in order to see the world. But when the optometrist is measuring the proper corrective power your eyes, it's important that you stop squinting for the first time in your life and let your eyes relax. Otherwise, you'll still need to squint even after you get your glasses or contacts.
So the same applies to tuning the MgR/I value of your racquet. You can't tell whether your MgR/I value is tuned properly if your wrist is not fully relaxed.
If your MgR/I value is slightly lower than your optimum, when you swing with a completely relaxed wrist, the racquethead will lag behind the hand at the moment of impact, causing you to naturally push your shots wide right (assuming you are righthanded). You need to resist the temptation to compensate by applying force from the wrist. It's kind of like when golfer has a slice swing and is less accurate because he has to always compensate for it.
Conversely, if the MgR/I value is slightly above your optimum, then when you swing with a completely relaxed wrist, the racquethead will get ahead of the hand, and you will tend to pull your shots to the left. The temptation here might be to convert the extra angular velocity into more topspin, but again you need to resist.
When your MgR/I value is perfectly tuned, you can simply fling your arm at the ball with a relaxed wrist, and the racquet will naturally stay perpendicular to your target all of the way through the hitting zone. This means that slight timing errors do not get punished. And you will notice that your targeting accuracy when hitting against the wall improves dramatically.
When my MgR/I value is tuned, I can hit a ball within a 1x1 foot square target almost every time. But if my racquet is slightly off, I can't hit as accurately. Compensating for the mistuned angular velocity might allow me to consistently hit the ball within a 3x3-ft square target, but why settle for that? That difference in accuracy is often the difference between winning a match and losing.
If MgR/I is too low, you can add a little more lead to the top of the handle. If it's too high, you can either remove some lead from that spot or add a dab to the tip. Don't settle for almost! Keep adjusting until you get that "in the zone" feeling.
When you are tuning for the first time, you might find it helpful to keep going beyond where it feels good until it's obvious that you've gone too far. You need to learn the difference in feel between MgR/I too low and too high.
Following all of these steps takes a lot of care and patience, but the end result is worth it.
Pro Staff 4.7 EB Stretch OS; 13.545 oz., 12.55", 365 SW.
Kevlar 18g / SS 17g, 65 lbs., top and bottom X's and outer M's skipped.
Source : http://tt.tennis-warehouse.com/showpost.php?p=5859118&postcount=17