So how do we address these differences? Shirley Sahrmann discussed this topic in a lecture that we highly recommend listening to. Instead of focusing on the side with increased stiffness, we should address the side with decreased stiffness. Strength training has been found to increase muscle stiffness (Magnusson, 1998). By bringing both sides of the body to symmetry (equal stiffness), an equal distribution of forces prevents any abnormal stresses on the body. Stretching still has its place, of course, but we must be sure to distinguish between muscle stiffness and adaptive shortening when choosing to apply the intervention. Next time you're measuring muscle length, check for stiffness and muscle length!
Magnusson SP. (1998). Passive properties of human skeletal muscle during stretch maneuvers. A review. Scand J Med Sci Sports. 1998 Apr;8(2):65-77. Web. 10 June 2013.
Mizuno T, Matsumoto M, Umemura Y. (2013). Decrements in Stiffness are Restored within 10 min. Int J Sports Med. 2013 Jun;34(6):484-90. Web. 10 June 2013.
Mizuno T, Matsumoto M, Umemura Y. (2013). Viscoelasticity of the muscle-tendon unit is returned more rapidly than range of motion after stretching. Scand J Med Sci Sports. 2013 Feb;23(1):23-30. Web. 10 June 2013.