Explosiveness is something we all seek to develop in the gym, and there may be nothing better for it than contrast training. In contrast training, we mix lifting heavy weights with 'explosive movement that mimics the mechanics of the heavy lift'. The point here is to develop post activation potentiation (PAP), which fosters explosiveness.
We're grateful to LA-based trainer Stephen Cain who posted this video with a boxing-infused contrast workout, with a complete breakdown of the reps and recovery times.
It's no surprise that contrast training is popular with rugby teams. If you're looking for your own contrast workout to build off, try the above.