I think the situation of what’s good for your body is a case of looking at many variables, not just one. If you are 2m tall and weigh 110 km you are probably going to use a heavier racquet than a 160cm person weighing in at 58kg. So that’s one variable;
Then you have things like your playing level, playing style and strengths, your age and your racquet history are all relevant factors along with pre existing injuries.
If we generalise a heavy racquet ( say 355g strung for example ) with a swing weight of around 330, well it’s going to be very solid and stable and it’s going to suit your traditional attacking type player who plays a lot of singles and likes to hit a heavy serve and come to the net. The racquet will absorb a lot of shock and won’t flutter when you try to place your volleys. However if you are an ageing player you may find that this spec will make your shoulder get tired especially by the time you are late in the 3rd set and this will affect the small tendons in your shoulder. The other thing of course is the beam type and lay up, the flex and the grip choice and string type and tension. Imagine using a Volkl C10 Pro or Pro Kennex Q Tour 325 if you haven’t played for a while and then play a long match. The current Q Tour 325 is not only a heavy frame with its 331SW but the shape of the beam and the lay up
of graphite and kinetic beads is such that it can be quite cumbersome to swing unless you are a very strong person.
Naturally as the racquet gets lighter it’s going to help small in stature players, those with modern styles and doubles players a bit more. The thing is however is that as the racquet gets lighter the manufacturers have to put more weight in the head and up the stiffness level, so that the racquet will remain stable at impact. Unless you are a small person, once you get a racquet that comes in under 300g unstrung weight with a strung swing weight in the low teens, well it’s going to be generally quite stiff and likely to be a more unstable which is why you shouldn’t string racquets under 300g in polyester, it will vibrate too much and cause problems.
The last thing I would like to share on this topic is that whatever racquet one chooses, make sure you test the racquet put in match type situations. That I feel with give you a true indication of whether the racquet is right for you or not.