Complexes, chains, or hybrids have been used by Olympic lifters for decades to help prevent overuse injuries and build better general physical preparedness and improve all round fitness levels. You can also use complexes to prepare for the real work of your training session. The goal with complexes is to do a wide array of functional movement patterns to develop muscle balance, explosive power, strength while training in multiple planes.
When it really comes down to it, complexes are a great way to get a lot of work into a short amount of time which at the end of the day turns your body into a metabolic fat-burning machine!
The video below demonstrates 3 complexes with a sandbag, which are perfect for a quick workout. Check out this 3-tier complex:
There's no excuse for not having a sandbag to train with!