I recently started a practice routine to try and improve my speed. It's about an hour long of various 2, 3 and 4 finger runs up and down the neck.

Although its helped my playing, I've noticed that my wrist is getting fatigued. If I do the routine more than 2 days in a row, its really noticeable. I also find if I went to the gym that day its more noticeable.

It's not really wrist pain, its more like fatigue. It just feels like my fingers are too tired to get where I want them to go at speed. Kinda like if you were playing basketball and you were really tired, you could still do everything, but you might plod a bit, and move slower.

I've focused a lot on tension, and have found that lately I've been pushing on the strings a lot less, about as lightly as I can, while still fretting. I've also been doing hand and wrist stretches before and during my practice.

So far no pain though. Is this normal? Or is this a sign of tendinitis?