Hip Hike
Stand sideways on the bottom step of any staircase and hold onto the railing for stability. Scoot to the edge of the step so that you're only standing on your right foot, with your left foot dangling next to the step.
Put your body into proper postural alignment—earlobes, shoulders, hips and ankles all in line from the side; hips and shoulder square and level from the front. Slowly dip your left hip down, lowering your left foot a few inches from the floor, then contract the muscles in your right hip to raise your hips back to level so that your left foot is even with the right foot again. Perform 15 to 20 repetitions, then switch sides and repeat.
How you become a better runner: Many common running injuries are the result of weak and under-activated hip and gluteal muscles. This move strengthens the entire region.
More: 11 Exercises to Boost Hip Strength
Swimmers
Lie facedown on a mat with arms stretched out overhead. Slowly raise your right arm and your left leg 4 to 6 inches off the floor. Keep your arm and leg traveling straight up and down, without allowing any rotation in the hip and shoulder joints. To do this you'll have to actively engage the gluteals, the muscles all along your spine and the muscles surrounding the working shoulder.
Lower your arm and leg to the floor, then alternate, raising your left arm and right leg. Continue in this fashion, doing slow, concentrated, alternating repetitions for a total of 20 to 30.
How you become a better runner: A strong back is key to good running form and this move effectively targets the entire back, as well as the gluteals and the rear deltoids.
More: Should You Change Your Running Form?
One-Arm Plank with Twist
Start in regular plank position (the "up" position of a push-up) with body weight distributed evenly on both hands and feet. Lift the right hand off the floor as you open your chest and twist your torso, extending your right arm up toward the ceiling (you should be in "side plank" position now). Bring your right arm down, reaching under your body, through to the other side.
Place your right hand on the floor and repeat the move on the other side. Start with a total of eight or 10 total repetitions (four or five on each side, alternating) and work your way up to 20.
How you become a better runner: This advanced exercise targets the entire core while promoting upper body strength and range of motion in the shoulders and spine.
You can complete this circuit workout one to three times and perform the workout two or three times per week.
More: 30-Day Plank Challenge
Find more running tips and tricks.