" Why do my wrists hurt when I play piano? "

A viewer to my YouTube channel posed the following question "Why is it that sometimes when I play the piano for over an hour my wrist hurts,especially when I play that song [a Clementi sonatina]? Most of the times I play once a week. Are the pain in my wrists normal? I am 38 years old."  

I have suffered from short-term wrist pains once in a while.  For me there are only three causes:

• Hitting the piano too hard.  Many years ago I accompanied an operatic society chorus singing 'With cat-like tread' from Gilbert & Sullivan's 'Pirates of Penzance', which has sudden loud chords.  I was playing a Steinway in a large theatre, and I hit the chords harder than I would on smaller pianos, and had a wrist-ache for a month afterwards!
• Sitting at the piano at the wrong height.  I always play so that my lower arm rests very slightly lower than the top of the keys.  Others will like different heights.  I am very particular about getting this right, else I certainly would suffer from a wrist ache after only a short practice session.
• Having stiff shoulders.  I like to play with the whole arms - there is a balletic aspect to music making whatever instrument you play.

If you think about each of these points maybe you will find the answer.  Wrist pain is certainly not normal at 38.