A lot of problems arise when players don't use their free arm properly. It's a major problem with a lot of players. Here are two common problems.

First, many players let their free arm just sort of hang down instead of holding it up as a counterbalance to the playing arm. Every time they stroke the ball there is no counterbalancing arm to act as a counterweight, and so they are thrown slightly off balance with each shot. Worse, they become so used to this they don't even realize it is happening. The cure - hold the free arm up for balance at all time, wrist about as high as the elbow, and let it naturally counterbalance your playing arm. Note that this is true on backhands as well as forehands. On the forehand, the counterbalancing is more obvious. On the backhand, as you extend your playing arm out, the free hand needs to counterbalance this by naturally pulling back slightly.

Second, when hitting forehands, players don't use their non-playing side. You should pull with the non-playing arm as you rotate around on the forehand. The non-playing side (the left side for righties) is just as important as the playing side when you hit a forehand. Your body can't rotate properly unless both sides rotate.

Here's a video of the two best players in the world right now, world #1 Ma Long and #2 Zhang Jike of China (15:29), playing the final of the Austrian Open in September. Watch the way they use their free arm on each shot. (Of course, you can learn a lot from this video besides just the use of the free arm!) 

A lot of players have good forehands in practice, either looping or hitting. But once a game starts, they stand facing the table, which is a backhand stance, and while their backhands are fine, when the ball goes to their forehand they mostly face the table, bringing their arm back to stroke rather than turning sideways. This leaves them with an awkward forehand stroke. They have only a small hitting zone, and this small hitting zone is jammed over the table. They have no time or space to actually do a normal forehand swing, and so end up blocking or doing awkward strokes. Their stroke is almost entirely with the arm.

Afterwards, they go to the table and spend hours practicing their already-good forehand, never understanding why they are unable to use it in a game situation.

The key to fixing this problem (which afflicts most players at most levels to some degree) is to learn to open up the forehand zone. This means that somehow you have to turn your shoulders so they are roughly perpendicular to the table, i.e. parallel to the flight of the incoming ball. Once in this position, you can unleash your true forehand power with control and consistency. But how do you do this in a game situation, as opposed to just facing the table and bringing the arm back?

You do so by, in varying degrees, bringing your right foot back (for righties), turning at the waist, and turning the shoulders. You need a combination of all three. Players with quick feet might bring their back foot back more than others. Players with a more supple body might rotate more at the waist and shoulders. But the result must be the same - sideways to the table.

The problem is how to develop this habit? Here are two suggestions.

First, do a simple drill where your partner hits the ball side to side, and you alternate hitting backhands and forehands to the same spot (either partner's forehand or backhand). When the ball goes to your forehand, focus on pulling with your right side so that you rotate completely about, perhaps even exaggerating it at first. The goal is to develop this habit of opening up the forehand zone.

When you are comfortable with this drill, do the same thing, but now have your partner hit the ball randomly to your forehand and backhand. Do it slow at first - the goal is to do it properly, or you'll just re-enforce bad habits.

Second, consider hitting your backhands with a slight forehand stance. You probably don't want to do this if you are looping your backhand, but for blocking and hitting many players keep their right foot slightly back, making it easier to transition to the forehand. (I often do this.) Experiment with this.

Trust me, if you have a good forehand in drills, you can do it in games, as long as you actually do it in games the way you do in practice - with the full forehand zone. 

Most players learn early in their table tennis lives the importance of moving opponents side to side, playing the three spots - wide backhand, wide forehand, and the opponent's middle (the transition point between forehand and backhand, usually around the playing elbow). However, a quote from a Dan Seemiller camp from many years ago has always stood out for me. He said moving an opponent in and out was even more important than moving them side to side.

The two main examples of this are:

• Serving short or pushing short, and then attacking deep, especially if you use the diagonals, i.e. go short to the forehand and attack the deep backhand, or short to the backhand and attack the deep forehand. Or in both cases, after dropping the ball short, attack the middle.
• Forcing an opponent off the table in a rally and then dropping the ball short with a drop shot or dead block. Again, use the diagonals when possible, dropping to the short forehand and attacking the deep backhand, or short to the backhand and attacking the deep forehand. Or in both cases, after dropping the ball short, attack the middle.

In both of these cases you shouldn't always go short and then long; often it's better to go short a second time, catching the opponent as he moves back to react to the expected deep ball.

These types of tactics are rare at the beginning level, are used by some at the intermediate level, and are central to most advanced games. At the recent U.S. Olympic Trials, match after match had players mixing up short serve returns and attacking serves, with the server sometimes tied up trying to cover for both. Most serves were short (or half-long, i.e. second bounce near the end line), and if it was returned short, the server would either attack or sometimes drop it short again, forcing the receiver to cover for both.

Once an opponent is forced off the table, most players keep blasting the ball until they win the point. In most cases, while a short ball may set up the attack that forces the weak ball to put away, once you get that weak ball it's often better to keep attacking until you win the point. However, against a player who is returning your attacks consistently from off the table, sometimes it's better to take something off the attack to throw off the opponent's timing, and then blast the next ball. For example, if you are having trouble getting through the opponent's fishing or lobbing defense, throw in a dead block to bring him in, and then attack again with the opponent now too close to the table to defend. Dan Seemiller, both now and when he was winning his five U.S. men's singles titles, would constantly mix up strong attacks and dead blocks.

So learn to turn your opponent into a marionette, and learn to yank his strings as you move him in and out.

A low, heavy backspin serve is difficult to attack, especially if you serve it short or to the opponent's weaker side. For that reason it is often the serve of choice for many attacking players who are looking for a passive return to attack. However, there are several problems you face with this serve. If you serve with heavy backspin, it's easy for an opponent to dig into it and push it back low and heavy - your own backspin rebounds off their open racket with backspin. If you serve it long, it's easy to loop with heavy topspin, converting your own backspin into topspin. If you serve it short, it's easy to push back short and low, making it difficult to attack. How do you overcome these problems?

The answer is to develop other serves as variations, such as a good sidepin or topspin serve - and you should develop these. However, there's an easier way that most top players use, and that's to mix in no-spin serves.

A key to getting heavy spin on the serve is to contact the ball near the racket tip, which is the fastest moving part of the racket when you snap your wrist into a serve for heavy spin. Suppose you use the same motion, but contact the ball near the handle, where the racket is moving much more slowly. You get an almost spinless ball. If you really exaggerate the spin motion but serve with no spin, it's a "heavy no-spin serve."

Now it's more difficult for an opponent to push it back heavy as they can't use your spin against you, plus they are probably expecting backspin, and so their push pops up. If the serve goes long and they attack it, they'll likely misread it as backspin, and go off the end. If they try to push it back short, it'll likely pop up as well as go long.

It's extremely important to serve no-spin very low to the net. There's no spin to directly mess up an opponent, and if it goes high, it's easy to attack. If you serve it low, it's surprisingly difficult to flip aggressively - if an opponent does attack it easily, you are probably not serving low to the net.

At the higher levels, no-spin serves are the most common serve in doubles, often with backspin serves mixed in as the main variation. Since your opponent knows which court you are serving to in doubles, he is camped out ready to make a return from his stronger side. At these higher levels, deep serves are looped, short sidespin and topspin serves are flipped aggressively, and short backspin serves are dropped short and low. Since the opponent can use your own spin against you, the no-spin serve is often more effective than the spinny one. A short no-spin serve may not force as many outright mistakes, but there's no one easy way to return it effectively.

So develop a no-spin serve as a variation to your spin serves, and learn to really load up the ball with so much no-spin that no opponent can possibly overcome that dizzying lack of spin you throw at them.

The hooking sidespin loop had its heyday in the early 1970s, with the rise of Hungary's Istvan Jonyer, the 1975 World Men's Singles Champion. Jonyer looped with a straight arm, and would often contact the ball on the far side, hooking the ball to the left (he's a righty) with incredible sidespin. Often his racket tip would point straight down at contact, giving him essentially 100% sidespin. When players went to his forehand side, often he would loop around the net, with the ball barely rising above table level, and mostly rolling when it hit the far side - nearly unreturnable. Primarily because of Jonyer, the rules were changed, requiring the net to project six inches outwards. This makes around-the-net loops rare, though top players still do this shot sometimes from the very wide forehand.

However, while we may never see the sidespin dominance of a player like Jonyer again, most loops do have sidespin on them. According to former U.S. Men's Coach Dan Seemiller, your typical forehand loop should be about 15% sidespin. This is the most natural loop - for most players, it would be tricky going for 100% topspin, as the racket naturally tips downward from the shoulder, and contact point is usually below the shoulder.

Yet some players like to go for extreme sidespins on some of their loops, especially on the forehand side. It's a great way to mess up an opponent and set up your own shots. How and when do you do it? This is one of those shots where if you see a top player do it, it's easy to copy.

The basic key for a hooking loop is contact the ball on the far side, by dropping the wrist so that the racket tip slightly down. It's generally easier doing it from the wide forehand, though you can do it from anywhere on the court. When someone blocks to your wide forehand, and you have to stretch for the ball even a little bit, it's best to get your racket outside the ball and hook it back with sidespin as well as topspin. If you do it to the opponent's wide forehand, it jumps away from him, and the sidespin will both make his timing tricky and make it difficult for him to return it to your now open backhand side, and so you'll usually get another forehand shot.

The opposite of a hooking sidespin loop is a slicing one (also called an inside-out loop), which is often done with the forehand from the backhand side to the opponent's backhand side (so that it jumps away from the opponent), but it can be done from anywhere on the court. Instead of dropping the racket tip to hook the outside of the ball, you now raise your wrist so that the tip goes up, and contact the ball on your side of the ball so that it slices to the right (for a righty). This is usually a bit more difficult to learn, but once learned, it gives you a devastating one-two combo of hooking and slicing loops. Just as with a hooking loop, the slicing loop messes up the opponent's timing, and usually forces a return toward your backhand.

Here's a video from PingSkills that demonstrates and explains hooking and slicing (he calls them fading) loops (3:08). 

Tired of throwing the usual topspins and backspins at your opponent? Have a little sidespin fun!