The lymphatic system. 

The most important and powerful system in the body’s defense mechanism is the lymphatic system and did you know that using a trampoline will help you exercise your lymphatic system, which rids your body of bacteria, toxic wastes, fat globules, trapped protein and dead cells!

https://www.huffingtonpost.com/entry/how-does-the-immune-system-really-work_us_5a2315cfe4b05072e8b569ca