Use a weight belt once you approach your 90% of 1RM threshold. Wearing a weight belt allows for greater intra-abdominal pressure and stability. But lifters often make two mistakes.
- Pulling it too tight to the point where they can't push into the belt to create intra-abdominal pressure.
- Pushing only the belly into the belt. This can be problematic. It causes an exaggerated arch in the lumbar spine which can compromise stability. The better approach is to use 360 degrees of expansion, where you push air all the way around to the front, side, and back of the belt.