How can I spike harder?

1. A faster approach — slow to fast, with a big second-last step.
2. Both arms swing back then up to jump higher.
3. Bow-and-arrow arm: elbow high and back.
4. Rotate your hips and core into the hit.
5. Contact at full reach, in front of your hitting shoulder, and snap your wrist.

Timing with your setter matters more than raw strength.