Defensive backs are usually the most all around athletic players on the football field. A defensive back must keep up with a receiver, watch the quarterback, play zone, come up on run support, blitz and make tackles on larger players. Defensive backs are expected to be the fastest players on the field while also generating explosive power to make big hits.
A weight lifting routine for defensive backs should reflect the demands made on them during the game. Defensive backs should train heavy, like a linebacker, but for speed, like a receiver. They need to be decisive, explosive and extremely strong for their lighter body weight.
Day 1 Push - Chest, Shoulders and Triceps Defensive backs need shoulders and triceps more than anyone else on the field. They need to not only be able to bench press their own weight, but do it in explosive fashion. Just imagine the surprised look on the receivers face when you go to bump on the snap and knock him on his butt. Bench press - 5x5 Dumbbell bench press - 3x8 Incline press 5x5 Overhead dumbbell press - 3x8 Reverse cable crossovers - 5x5 - At the cable crossover station set the cables all the way at the bottom. Grip the handles over hand with opposite hand so that your arms are crossed in the starting position. Explosively pull up the cables across your body and out with your shoulders to end in a position like a lateral raise.
Day 2 Pull - Back, Biceps and Forearms Defensive backs need a strong back and biceps to wrap up tackles. They also need powerful forearms to grab cloth and bring down ball carriers when they can't wrap them up. Dead lift 5x5 Dumbbell row 5x5 Lat pull down 5x5 Bicep curls 3x8 Finger curls 3x12 - Let the bar roll down to hand on the tips of your fingers, then close your hand to roll the bar back up into your palm.
Day 3 Legs - Glutes, Hamstrings, Quads and Calves Defensive backs need powerful legs to drive through tackles and keep up with receivers. They must train for power as well as speed to be successful and well rounded on the field. Split squat 5x5 Speed squat 3x8 Hang clean 5x5 Stiff leg dead lift 5x5 Leg curls 3x8 Jump calf raises 3x12 - holding dumbbells in each hand jump up using only your calves.
Remember to keep all exercises explosive to build power. Heavy weight does you no good if it is lifted slowly. Do proper warm ups and stretch during your cool down so that you can keep up with more limber receivers.