Most players find it more difficult to create power on the backhand side. This is because the body limits the backswing on that side. However, with proper technique (and a lot of practice!), one can create nearly as much power (and perhaps more!) on the backhand side as on the forehand.
The most important power shot in table tennis is the loop. Although many players develop good forehand loops, many do not bother learning the backhand loopseriously handicapping their games. This is especially true of shakehands players, who have a natural backhand loop when done properly. (Penholders generally do not backhand loop, but in recent years, more and more of them have learned to do so by using the back of their penhold racket.)
If a player has a forehand loop, but not a backhand loop, a simple short serve to the forehand, followed by a quick push or block to the backhand takes away this player's looping game. Even a very fast player cannot cover all of the table all of the time with just a forehand loop.
The backhand loop can be done against just about any type of shot. It is easiest to learn against backspin, but can also be done against topspin or a block. One advantage of the backhand loop over the forehand loop is that a player can often "wrist loop" a short ball on the backhand sidesomething that is more difficult to do on the forehand side.
A Newgy robot is an excellent way to learn to backhand loop. Set the robot on backspin, and aim it toward your backhand corner. Set the speed dial on 2. The robot will give you a pretty heavy backspin, so you will have to lift the ball.
When you feel you are comfortable looping both backhand and forehand, you should learn to loop from all parts of the table. Use the Newgy robot's oscillator to randomly put balls all over the table. Cover 50-70% of the table with your forehand loop, the rest with your backhand loop.
What follows is a sequence of Sean Lonergan, 1998 U.S. Collegiate Men's Singles & Doubles Champion. He is practicing on a Newgy robot, set on backspin, with the speed dial on 2.
The key thing to note about this sequence is how Sean uses nearly his entire body in the shot. Power is generated by the upward push of his legs when he unbends his knees, by the upward thrust of his upper body from the waist, by the rotation of his waist, by the rotation and upward thrust of his right shoulder, by the rotation of his arm on his elbow, and by the last-second snap of his wrist.
(Editor's Note: There are 8 GIF files that Larry has included with this article. The first seven are still pictures, and are great for studying the details of each phase of the stroke. The last picture is an animated GIF made from the 7 previous files. This file takes a while to load, but once loaded it will "play" all 7 still pictures in sequence, giving motion to the pictures and providing the viewer with a good idea of the "feel" of the motion and how one phase of the stroke leads into the next phase.)
Photos 1-3: Backswing
Sean bends his knees, and bends and rotates his waist to the left. Some of his weight is transferred to his left leg. He rotates his right shoulder forward and slightly down, and brings his racket down to knee level, between his legs. (Against topspin, he would swing more from his left hip.) His wrist is cocked backward so his racket tip points almost straight backward, with the racket face pointing nearly straight downward. Sean's elbow is well out in front of his body. Sean is balanced, with legs well spread.
Photos 4-5: Forward Swing and Contact
Just before starting the forward swing, Sean's wrist is fully cocked backward. He transfers some of the weight on his left leg to his right leg. His knees and waist begin to straighten, and his right shoulder lifts upward and rotates backward. His waist rotates forward. The movements of the knees, waist and shoulder together start the forward swing of the arm. Sean's arm rotates forward from his elbowa motion similar to throwing a Frisbee. Just before contact, Sean's wrist snaps into the ball. Contact is made a little to his left, roughly in front of his left leg.
At the start of the forward swing, Sean's racket was pointing nearly downward. As it moved forward, it opened up, until at contact it is facing nearly straight forward.
The contact is a grazing motion. The finer the grazing motion, the more spin. If the ball sinks into the sponge more, there will be more speed. The ball should not sink all the way through the sponge to the wood. Sean's backhand loop is a good balance of speed and spin, although he can go for extra spin or speed on any given shot.
Photos 6-7: Follow-through
The follow-through is the natural progression of the racket forward and up. Sean's racket ends up about head level, to his right.