I had shoulder and elbow pain whenever i played with a head heavy racket in badminton and i checked with others also and they also had varying amounts of pain

I found that via Google that its a common problem. I eventually found a solution by trial and error / by accident.

Doing few reps on Dumbbell the day before you play and just before you go out to play actually solves the problem. It doesnt actually take that long. Just 5 mins of DumbBell exercises.
  • Hold the dumbbell away from your body at chest height and try to hold it there for 10 seconds (Can increase it with time).
  • Lift the dumbbell up and down slowly 10 times - away from your body
  • Push the dumbbell up from your shoulder as high as you can and bring it back to your shoulder
  • Hold the dumbbell facing up and turn the wrists inward and back

Doing this ensures that your arm muscles and wrists warmed up and ready to handle a head heavy racket.

As a adult, our lifestyle becomes dormant and without these basic exercises the arm muscles are also dormant and are not ready to take vibrations from violent smashes and swings of a head heavy racket.

Below are some options in Amazon if you are looking to buy a DumbBell

Dumbbells - 4KG - Aurion Set of 2 PVC Dumbbells

Aurion Dumbbells (Boxed in Pair) (Choice of 1KG, 2KG, 3KG, 4KG, 5KG,6 KG)

Unishore PVC Coated - Pack of 1 Piece of 4 KG for Strength Training

Kakss Cast Iron Vinyl Coated Dumbbells