Posting this because three students hit the same wall this month, and the fix was the same every time.
If your octaves are uneven or your forearm burns after sixteen bars, the usual culprit is playing them from the fingers with a locked wrist. The checklist I use:
- Play one octave, then consciously release the wrist. Feel the drop? That release has to live inside the passage, not after it.
- Slow practice with an exaggerated loose bounce — looks ridiculous, builds the right motion.
- Group in fours: land-bounce-bounce-bounce. The accent is a relaxation point, not a tension point.
- The moment the forearm tightens, stop. Every repetition past that point is practising the injury.
Tempo comes from the motion being right, never from pushing the wrong motion faster.