Q2. I am reasonably fit but now I am getting older I have terrible trouble in recovering from hard games. Is there anything I can do?

A.2. Warm-down after your matches. Keep moving. The stiffness is caused by lactic acid, a by-product from the chemical reaction in all that energy you have produced to play squash. Flush it out by maintaining the blood flow with gentle exercise for 10 minutes walking or jogging. Perhaps even consider a light recovery run later in the day.
Stretch after a match when the muscles are nice and hot and pliable.

Q.3. I have an opponent who cuts me up on the volley. But for that I would be in the game. Do you have any advice?

A.3. The general rule if your opponent is playing winning shots or shots that are troubling you is to look at where he is playing them from – and don’t put the ball there.

Basically tighten up your game so there are no easy volley opportunities there. Probably you should straighten up and hit lower and harder under his volley reach area. (Unfortunately this may take some effort and there is also the danger of hitting short.) Try to keep the ball out of the air – certainly until you are in front. If you do stray there anticipate where the ball is going before it has been struck. It sounds as if you may know this is but are not moving early enough. There are other issues. Perhaps you are too readable and should vary your game more; you can play more short balls if you have that capability (although there are dangers in this); and you could try very high shots that will go over his volley reach area. Remember to volley yourself – of course! Perhaps you can get in first.