Saturday, October 17, 2009

Shenzhen Ping Pong: backhand forehand drill

It's been a while since I've blogged about ping pong.

(Last entry in a series about learning the basic reverse penhold backhand stroke is here.)

What hasn't been covered though is the integration of the reverse penhold backhand into the game. This one can do after initial acquisition of the stroke.

One can do this with any practice partner who can return or block a ball with reasonable consistency: a basket of balls can make up to some extent for a high-level player or coach (though it is likely more balls of higher quality will be returned by a good coach).

A first step towards integration is to be able to do drills where a practice partner will direct one ball to each side of the table in turn. This kind of drill, as opposed to the "static" kind (in which the ball is directed to the same side each time), significantly increases the difficulty level because one is forced to move, adjust and recover in rapid succession. It is one thing to be able to consistently play the ball from one side only, quite another to be able to do it on the fly.

Any weakness in set up and balance not apparent during a static drill will be exposed here, manifesting as poorer quality shots as the rally progresses from the first ball to subsequent ones.

The following Youtube clip took place in Warabi (蕨) municipal sports center in Saitama prefecture (埼玉県), just outside metropolitan Tokyo but nearly 3000 km from the practice tables of the Century South China Club in Shenzhen.

(My friend Hideya Watanabe is my willing practice partner. The drill is to drive the ball back to his backhand side irrespective of whether the ball comes to my forehand or backhand.)


(Direct link: here.)

Viewing a recording of the drill is especially helpful in spotting weaknesses and details that one can earmark for improvement next practice.

(As I'm also using the forehand stroke, I can see that it needs work in setup and followthrough... but that's another topic!)

Of course, having a good coach give immediate and helpful feedback during the drill is even better.

Fitness-wise, having to move from side to side and hit balls at the rate of nearly one per second can be an aerobic challenge. On this drill, I go through one basket of balls in about 5-6 mins. I recuperate by returning the favor to my friend by feeding the ball for him.

BTW, this drill also illustrates the value of the reverse penhold stroke, I simply cannot imagine doing this drill using penhold forehand only: the amount of footwork required would be staggering!

More drills to come...

Sunday, October 11, 2009

iLasiked

I got iLasiked recently.

I've thought about it on a number of occasions but haven't pulled the trigger until now.

One only has one pair of eyes per lifetime, and online accounts of unsatisfactory outcomes and medical complications on http://www.lasermyeye.org/forums/ and http://www.lasikcomplications.com/ are enough to give anyone cold feet.

On the other hand, as someone who has been quite myopic (with significant astigmatism) since childhood, the idea of waking up and being able to see a clock without first fumbling blindly for glasses is quite an attractive and novel concept.

Moreover, it'd be nice to ditch at a stroke all the special eyewear for sports that I've accumulated over the years, e.g. prescription googles for swimming, and a prescription facemask for snorkeling and scuba diving. Contact lenses for running and table tennis to avoid sweat causing glasses to slip or become streaked and unclear. Two pairs of ski googles: one to fit over glasses, another for use with contacts. Why not ditch the glasses and just use contacts? I have soft toric lenses but for use on computers or reading, my eyes get easily tired. So I use glasses for those tasks. Also, I can't safely wear contacts during cycling even with eye protection: 50+ mph descents can tear at and dry out one's eyes, putting the lenses at risk of falling out. Moreover, for ultra-distance events, a 24 to 60 hour bike ride with contacts can be quite a trial.

I had an initial 2 hour consultation at an English-speaking clinic in Tokyo where they determined without sales pressure that I was an excellent candidate. Several days later, I returned and paid 360 000 yen ($4000 US) to undergo iLasik surgery, which is supposed to be state-of-the-art.

The operating room:

(iLasik stands for the two stage IntraLase (laser eye flap cutting: the machine on the right) and Visix (customized map laser correction: machine on the left). iLasik, IntraLase and Visix are all registered trademarks of AMO (Abbott Medical Optics) Inc., the current industry leader in Lasik treatment.)

You can read about the procedure on many places online. But for the record, here are a few pictures from my surgery:


Don't worry, you can't blink during surgery. And with anesthesia, you can't feel a thing but I swear you can smell the burning as the laser zaps your eye...

Pressure ring is placed on the eyeball for IntraLase.
Can you see the semicircular cut the first laser made?
Visix zones projected on my eyeball.
Post-surgery, I was supplied with various eye drops for use five times a day for the initial one week period:
  1. Dexamethasone: an anti-inflammatory
  2. Antibiotic drops
  3. Hyalein and Hyalonsan to cure corneal laser cut and dry-eye symptoms
  4. Oxybuprocaine: anesthetic drops for pain
I ended up taking items (1) through (3) only. And after the initial 24 hour check-up, I was told I could discontinue (1).

After one week, I was cleared for sports again. You cannot spot any laser cut. And I'm down to using just Hyalonsan lubricating drops.

There are risks with iLasik of course. You can pick the best/most experienced doctor you can find (mine had done over 30,000 operations), make sure you're an excellent candidate and follow all instructions carefully.

For example, pupil size and corneal thickness are important parameters. People with large pupils are likely to experience significant night vision problems such as halos and starbursts. My pupil size is 4.88mm normal and 6.2mm dilated, so that helps to minimize those effects. Secondly, my corneal thickness is an above average 575 microns. After correction for my 5.75 diopter prescription, I still have around 450 microns left.

I'm told it will take perhaps 3 months for my final correction to take. Since it has only been just over one week, all I can point to are my impressions and the visual acuity testing results.

Impressions: Immediately afterwards, cloudy vision. Halos and starbursts are pronounced at night.

One day later: there is a slight but noticeable haze during the day but otherwise distance vision is serviceable. Night vision is better but not as good as with glasses or contacts.

One week later: haze is gone. Halos can be noticed but don't impede night vision. Same goes for starbursts. I am not entirely starburst-free with contacts or glasses in the first place either. Driving or riding at night is fine.

I hope these effects continue to diminish in the coming months.

Visual acuity: 1.0 in the Japanese system is equivalent to 20/20 American. (A figure higher than 1.0 corresponds to a rating better than 20/20.)

Before LasikNext dayOne week
Right eye 0.03 (Japanese)1.2 1.2
20/660 (American)20/1720/17
Left eye0.02 (Japanese)1.01.5
20/1000 (American) 20/20 20/13

I'm told the vision might continue to improve and stabilize over the first 3 months. (I will update this table after the next check.)

Unfortunately because of my age, I still need reading glasses for computer use and for close-up reading. Next step? Investigate by means of a contact lens whether a separate CK operation is appropriate to fix my presbyopia or would it compromise my newly corrected vision too much...

Four month report:
  • Haven't used the eye drops for a while now. No more dry eye even after waking up.
  • Halos and starbursts are not noticeable at night at all.
  • Vision is pretty good but not perfect. In low contrast situations I sometimes notice there is a faint ghost 2nd image, especially with text.
  • After 3 months, I bought some (low strength Bausch & Lomb) presbyopia-only contact lenses to try. It's based on the principle that the center of the eye is used for near vision and the periphery for distance vision. Yes, it improves my near vision (for reading) but there is a small cost in distance vision acuity.

    It's a tradeoff. At the moment, it seems like reading glasses are less of a hassle and can be higher strength for better magnification/easier reading.