Some things which have helped me:

• Walking and jogging every day, without exception. The Endorphins will decrease the Cortisol and Adrenaline levels (the stress chemicals).

• Outsourcing work

• Camping

• Lifting weights

• Telling your clients, friends, boss etc that you need a break and take it.

• Deal with the sources of the stress (this is more important than anything else if you are burned out).

Cheers.