This really isnt complex in a real world on court practical sort of way.
In a nutshell, batspeed is your friend..it is almost always better than choosing more mass...batspeed is your friend...know the swingweight which is best for you, and use something you can reliably flush hit
Nobad is correct in the sense that increasing racquet speed is always the easiest way to increase ball speed. Let's consider an example. Suppose you have a racquet with a power potential of 40% at the hitting location. The ball is coming at you at 30 mph. You swing your racquet such that the hitting location is traveling at 60 mph. The ball will leave at 96 mph.
Of that 96 mph, 37.5% of the final speed is due to the bounce from the racquet (power potential). The rest, 62.5% is due to the speed of the bounce pad (racquet) from which the ball bounced (from the formula that ball speed = bounce speed + bounce pad speed). For most groundstokes where the racquet is traveling faster than the ball, racquet speed is more important to ball speed than is power potential (which depends swingweight). If power potential is 40%, then every 1 mph you increase swing speed, you will increase ball speed by 1.4 mph.
But for a given swing speed, you want to maximize ball speed by having the highest swingweight you can comfortably swing. That's evident by considering what happens if you lower swingweight too much in an attempt to gain swing speed.
As swingweight gets lower you have to swing even faster to get the same speed. So, if instead of 40% we have a power potential of 20% (because we have lowered swingweight so much), then, for the same 30 mph incoming ball speed and 60 mph racquet speed, our outgoing ball speed is 78 mph. To make up the difference of 18 mph we have to swing about 10 mph faster. Perhaps the lower swingweight allows us to do that. But who wants to be swinging that fast for the same result? Accuracy and control go down and shock goes up.
Shock. That's a whole 'nuther' issue. Mass is always better at lowering shock. But even less shock can cause more strain on the arm if you are hitting late because of the extra mass. But on the other hand, swinging faster with less mass is going to blow your arm up too, even if your timing is correct. That's because the change in momentum due to the collision will have to occur by changing your racquet velocity much more for each gram of racquet weight than if the racquet had a greater mass (hittingweight) at the impact point. Momentum is mass x velocity. If you have many grams, each one has to change velocity less than if you only have a few in order to achieve the same change in momentum. Greater change in velocity of the racquet head compared to your hand means greater strain at the wrist.
So, as always, knowing these considerations helps you demo and experiment with racquets to choose the right combination of racquet speed and swingweight for you. If you know what the effects will be of changing variables, you will be able to analyze what is happening and why and then be able to change variables to meet your goals.
