A September 9, 2015 article in the New York Times brought to the forefront the work of Paul DeVita, a professor of kinesiology at East Carolina University in Greenville, N.C., and president of the American Society of Biomechanics. Dr. DeVita’s research compared the lower leg and ankle function of young runners in contrast to runners over forty years of age. His initial research in 2000 looked at gait changes with age at walking speeds, whereas his 2015 research data was gathered at running speeds. While the results are alarming, incorporating the study finding into your train
ing program will greatly reduce running-related overuse injuries.
The over 40-49 age group has seen a huge increase in numbers in the past decade. As a runner who was once a member of the 40-49 age group, I have experience the changes in running performance associated with age. DeVita’s research confirmed a 20% reduction in running speed per decade beyond forty. Both running stride length and lower leg muscle function decline in a linear manner with age. Calf (gastroc-soleus muscle) and ankle dorsiflexion (tibialis anterior muscle) functional strength both decline with age. A reduction in lower leg muscle strength and function shifts the burden of self-propulsion to our hips and glutes which are already physically challenged by prolonged sitting and tight hip flexor muscles.
Lower leg, foot, and Achilles tendon injuries become increasingly common in runners over forty. Gradual degradation of muscle and tendon tissue integrity and nerve innervation sets the stage for an increase in running-related overuse injuries. On a positive note, the information provided by Dr. DeVita’s research will serve to guide strength and conditioning programs for runners interested in injury prevention and running performance. Stretching the calf and lower leg muscles, Active Release techniques, dynamic warm-up, and rolling are great ways to improve lower leg muscle tissue mobility. Lower leg, ankle, and foot strengthening exercises should be a part of every runner’s training program, not just those in the fourth decade of life and beyond. Strengthening exercises should include single leg heel raises, heel drops, resisted ankle inversion/eversion/dorsiflexion, and intrinsic foot strengthening exercises. Of course, the gluteal musculature and core are not to be forgotten as older runners rely on these inherently weak muscle groups in the absence of full lower leg and ankle strength.
If you have been battling a lower leg, ankle, foot, or Achilles injury, email me your questions to determine how you can not only return to pain-free running, but also prevent future injury recurrence. Strength and muscle/tendon tissue mobility are the keys to running faster beyond your forties!
John Fiore, PT
Sapphire Physical Therapy
john@sapphirept.com
www.sapphirept.com
References:
Reynolds G, Why Runners Get Slower with Age. New York Times. 2015, Sept 9.
DeVita P, Hortobagyi T. Age Causes a Redistribution of Joint Torques and Power During Gait. J Appl Physiol (1985), 2000, May; 88 (5):1804-11.
DeVita P, Fellin RE, Seay JF, Ip E, Stavro N, Messier SP. The Relationship Between Age and Running Biomechanics. Med Sci Sports Exerc. 2015, Aug 7.
