Being fast or agile is pointless if you can't lift heavy things. The best choices for building strength are full-body movements like the deadlift or the squat.

I prefer to use deficit deadlifts as they have more carryover to the sports I compete in. And if you can deadlift something from a deficit, you can easily pull it off the floor. This movement also maintains and cultivates hip mobility and strength.

Related:  Building Hardcore Athleticism

Related:  Deadlift Challenge – 405 x 10