Once the domain of dancers, Pilates, a method that focuses on deliberate movements to strengthen the core, has become popular with runners. "When the core is stable, your limbs move efficiently, and you're less likely to be injured," says Julie Erickson, a marathoner and owner of Endurance Pilates and Yoga in Massachusetts. Do these moves three times a week.
More: 3 Best Core Exercises for Runners
Teaches you to engage your core and move your legs when tired.
From the top of a push-up position, pull your navel up and in and lift one leg, foot flexed. Point the toes of the top leg, flex the opposite ankle, and return the top leg to start. (Your arms stay straight but may move.) Alternate legs. Do five lifts per leg.
More: 4 Exercises to Strengthen Your Lower Legs
This teaches you to activate your core as your legs work. It also works your hamstrings, glutes, quads, and hip flexors.
To do: Lie on one side with your legs extended. Raise top leg to hip height and swing it forward and back, using a controlled pull/push motion (torso is still). Repeat 10 times on each side.
More: Why Your Hip Could Solve Your Knee Pain
Double-Leg Stretch Prep
This full-body move helps you support your limbs
with your core.
Lie on your back, as shown. Contract your abs. While inhaling, extend your legs (torso is still), turn your palms to the floor, and push your arms down toward your hips. As you exhale, return to the starting position with control. Repeat 10 times.
More: 5 Reasons to Strengthen Your Core
Practice this to fight the slouch when you're tired. It works your back extensors, hip flexors, and chest.
Lie on your stomach with your hands outside your shoulders. Contract your core muscles so that your belly pulls away from the mat. Look forward, and inhale while slowly lifting your torso. Hold for one inhale/exhale cycle; slowly return to start. Repeat eight times.
See a video of this routine at runnersworld.com/pilates
Tone up at a fitness class.