On the piano, a few pieces require me to play a gliss that can often run over a large range of notes, rather than a short range.
For example, I am currently learning the piece Maple Leaf Rag. There is a part when I am shifting my hands down an octave to repeat a section and during this shift, my left hand is supposed to drop down an extra octave-ish and gliss back up to the correct position.
However, when I do this, I often experience great pain during and after the gliss, and I might even experience numbness in the fingers for a few seconds.
In order combat this, I will often play a "lazy-gliss" and will end up just sliding my hand across the top of the keys.
What is a good technique for playing a gliss on the piano pain-free and still play all the notes clearly?