Replying to Improve tramp bounciness?

Hey NS,

I have a regular circle/garden trampoline, and the thing has been loosing it's bounce for a while now. You can only bounce on it for like 2 min before you're absolutely exhausted. Going to Sky zone or my local gymnastics place I can jump for 30min straight before I get tired, so it's not just me.

The main problem is, the tramp takes too much energy, and it only puts you about 2 feet up in the air. Is there any way to increase the bounciness of it? I do not want to buy another, I was wondering if there was any cheap solution to fix it. Thanks