My piano keys feel heavy on some days and light on others.. why?

[ryborn]

So....

I have this digital piano I practice on everyday for the past 7 months. I love it but the problem is that somedays I wake up and head to the piano the keys are like feathers, easy to press. Other days, most days, they feel super heavy and hard to play. WHY?

I play this piano about 9-11 hours every day, eventually they feel like lighter as I get deeper into practice but at the start of practice they usually feel heavy af. Is it my posture? idk, please help

[outin]

Are you serious? You play the piano 9 or more hours a day? No wonder the keys feel heavy in most mornings. For anyone but a professional working like that simply makes no sense. You don't just practice with your hands, you practice with your head. If your head can engage for that many hours you are a very unusual individual. If you are just hacking the keys for that long you are wasting your time...

I remember having such issues with my upright, which has very uncomfortable keys. But with my grand never, they feel the same everyday. I did have some RSI problems when I had to practice with the upright.