nothing beats the mellis/seges school food trick. But if you are raising endurance by hurting yourself:
1: why not do it fighting plants on UT3, bare handed so you can beat sumo, with banana peals for wicked dex gains/agi, with a broken halberd/scimitar and a shield for Astr, weapon skill, shield skill, and Agi from dodging.
2. when you are healing never heal using the heal command, just run back and forth in an empty corridor and you won;t suffer an agility penalty
I always pump my HP over 300 via mellis/seges it means you get to fight all the named baddies.