Anybody have experience here? Should I change my workouts? Are there things that have high priority that I should always do? Tennis-specific workouts are something that have always confused me, in that I don't know what to do.
The only highly specific stuff that most tennis players need to do is the anti-injury stuff, IMHO. For me that would include little exercises like rotator cuff work and y's and t's.
I don't agree that 'high loads' are an issue. You want loads high enough to facilitate strength gains via multi-joint movements. (Outside of the pre-hab stuff I mentioned) So this would be minimum 3-12 reps to failure.
Your goal with regards to lifting in the gym should be to actually get stronger. You should be seeing all your lifts increase. You should be choosing lifts that you can load safely to avoid injury. (For example you might choose a chest supported dumblell row over a barbell row to lower the lower back work)
If you are working out more then 4x a week in the gym and have progressed to fairly intense upper/lower body splits.. You can consider doing speed and agility work on your 5th and 6th days. This would include plyometrics, footwork drills, sprinting drills and so on.
This of course more tennis specific BUT rec players would be better served with more court time and court drills especially if they are doing this without guidance IMHO. SO this hardly comes up - except for pro/serious players who are getting alot of court work already.
I think the real problem is people think that doing a bit of off court work will make them into a monster hard hitter on the court and are disappointed that the lifts don't 'translate.' But you will learn to tap into your strength gains via practice on the court rather then mimic tennis mechanics carefully off court..
Take a powerlifter and have him play tennis and he won't hit all his shots with the strength of Djokovic. But the problem isn't that said powerlifter isn't strong. It's that he hasn't played enough tennis and doesn't have the muscle memory to be able to fire his muscles to maximize the use of the strength that he does have.
THis is why most of the time a 99lbs girl can outhit a full grown man provided the girl is semi pro. Less muscle - a ton less but they know how to use it.