By Kristen Aldridge
September 24, 2014
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You most likely remember Sophia Bush starring as a feisty high school cheerleading captain-turned fashion designer on One Tree Hill for almost a decade. But now the brunette beauty stars in a role we haven't seen her in before: a street-smart cop from the wrong side of the law, which surprisingly, she says isn't much of a stretch!

"I have a concealed weapons permit in 32 states and sleep with a loaded gun under my bed," she says. "This feels much more close to my soul than anything else ever has before."

While we're guessing she probably impressed the SWAT team she had to train with for the series (Chicago P.D. is back for its second season tonight!), she still had to look the part from head to toe. That's why she turned to powerhouse celeb trainer Patrick Murphy, who armed her with the strength, endurance, and agility to play Detective Erin Lindsay.

We went up close and personal with the fitness pro to steal his fighting secrets and even scored Sophia's exact workout routine for the show. So read on and get ready to sweat!

Shape: Tell us about your fitness philosophy.

Patrick Murphy (PM): My philosophy is to take each individual and to help them move better. It's that simple. I'm all about optimal movement and posture. I ignore trends, what exercises "look" the coolest, and even what "feels" cool. I take each individual's specific anatomy, and do what's best for that body. "Smart" training is sexy.

Shape: How long have you been working with Sophia Bush and how did you start working together?

PM: I started working with Sophia Bush this summer to help her prepare for season two of Chicago P.D. I've been working with another awesome Chicago PD. co-star, Jesse Soffer, since before season one. Jesse asked Sophia to give me a shot. For the last 20 years, my business has been built on referrals.

Shape: With such a fierce role, did Sophia have to learn any stunts or do any specific workouts pertinent to her character?

PM: Sophia takes her role very seriously. I know she experienced tactical weapons training and also learns from professional stunt coordinators. Her goals are to achieve high endurance, agility, balance, and body awareness. Sophia needs to be strong and stable to avoid any injuries during shooting. She kicks butt, that's for sure.

Shape: What did your workouts entail to achieve that?

PM: Sophia and I train with one-hour workouts, four times a week. We cover it all. Depending how Sophia is feeling, we interchange full body workouts and split routines. We accomplish high intensity circuits, super sets, and corrective exercises for optimal alignment and posture. Many of the exercises are compound, involving many muscle groups with each rep. Ever-changing workout programs defeat plateaus. Change evokes change. My workouts are high intensity. There is no time wasted.

Shape: What type of physical and mental changes have you seen since you first started to train together?

PM: Don't get me wrong, Sophia looked great when we started! The goal was to go for optimal, peak results. Through high intensity and varied training, we achieved even greater mental toughness and endurance. Sophia has great balance, flexibility, and strength. Get ready for Sophia to take charge in season two of Chicago P.D.!

Sophia Bush's Chicago P.D. Workout Routine

How it works: This is a five compound exercise circuit repeated three times. Rest one minute between each circuit, after all five exercises are completed.

You will need: Dumbbells, half ball, medicine ball, balance ball, mat.

Iso-Lunges with Dumbbell Front Raise

Reps: 15 per leg

Stay in lunge position while performing shoulder front raises (straight arm raise in front).

Alternating Reverse Stepping Lunge with Row

Reps: 20

Using a heavy band wrapped around pole, alternate legs while reverse step lunging and row on the bottom with each step.

4-Spot Dumbbell Punching and Pressing while Skipping Over Half Ball

Reps: 15

Using a half ball (bosu dome), skip side to side as you single arm punch and then vertical press: punch/punch, press/press.

Jump Lunging in One Place with Medicine Ball

Reps: 20

Jump lunge as medicine ball moves side to side over the forward leg.

Balance Ball Forearm Bridge Moving Arms Forward and Back and Side to Side

Perform a perfect forearm bridge on a balance ball and move forward and back (20 times) and side to side (20 times) in tiny movements.