When you serves in table tennis, do you lock your wrist on the free arm when you throw the ball upwards? Well, the wrist is natural like other shots while playing table tennis. Of course the higher the throw the more of the wrist movement. The lower, the smaller the movement, the harder to see.
For me, I believe in locking your wrist as your ball can be thrown consistently whether it is a high ball or a low one.
To get really good wrist action, in your spare time you should carry out some wrist exercises. For me, I have been doing those non stop and I have really really flexible wrists from which i dig out extreme spin. This is utmost necessary because I am dependent on my serve to set up an advantage!
For powerful wrist action, one can do the wrist curl with a dumb-bell. The exercise is kind of simple.
First, you may put your hand along your upper thigh while holding a dumb-bell with your wrist protruding out above your knee. Then slowly curl it downwards and moved it upwards. Do 3 sets of 10 repetitions. By practicing it frequently, this is one very effective way to strengthen your wrist.
For famous table tennis player like Michael Maze, I see him actually practice the wrist exercise in good way. Yes, Maze never ceases to amaze me with his serves set-up. You may take a look of the video to see how he does.
Anyway, I have seen different players used different methods, some lock their wrist, some do not. So it seems it depends on the individual preferences.
Will I get injured because of doing too much wrist exercises?
Do I actually injure my wrist in any way? For many people, they are having such concern and they are scare that if they are doing so much of wrist exercises, it will caused them to develop some kind of joint pain in the near future. Well, it is not to my knowledge that anyone who are having such issue for doing such exercise, unless you have carpal tunnel syndrome which will be a totally different story.
Anyway, I believe we will injure our body and arm more as we practice a lot on the forehand (FH) & backhand(BH) strokes more often as compared with the serves. However, if we always do the proper warm-up before our practice and game, we are going to reduce the risk of getting injured.