This is an excerpt from Beth Shaw's YogaFit-3rd Edition by Beth J. Shaw.
Because of the repetitive motion of the legs, running creates tightness in the hip flexors, hamstrings, and quads, often leading to low-back pain. Running also fails to strengthen the upper body or the abdominal muscles. The YogaFit poses here serve as counterposes to offset runners' lower-body strength and to provide supplemental work to increase total body strength, endurance, and flexibility. After a run is a great time to add in some fun arm balances and then move to the floor for increasing upper-body and core strength. Many runners find that yoga keeps them running longer and faster, without the nagging injuries.
Learn more about Beth Shaw's YogaFit-3rd Edition.