A few years back I had a painful bout of Carpal Tunnel Syndrome. Several occupational therapy sessions plus using two types of gliding exercises the therapist provided helped to reduce pain and restore strength in my hand: the exercises are shown in the pictures below, along with instructions. The CTS gradually faded away as I used the exercises, kept my wrist straight at night by resting my hand and forearm on a pillow while sleeping, and shed quite a few pounds (I had given up smoking and become enormously fat afterwards).
But, I learned recently that one of the symptoms of Carpal Tunnel Syndrome is difficulty grasping bottles and jars tightly. I still don’t have the strong grip I used to, so I pulled out the gliding exercises again and gee – they produced an immediate improvement to my grip. I think I should try them out again for a while. If you try them too, let me know what they do for you.