Researchers recruited runners in their 20s, 30s, 40s, and 50s, and had all of them run on an instrumented treadmill while filmed by high-speed video cameras. The subjects ran at their normal training pace. For a 20-year-old, this averaged 5.10 per kilometre. For a 60-year-old runner, 6.24 per kilometre. The decrease in pace was highly correlated with a shortening stride and loss of ankle power.
While the paper calls attention to the ankle joint, measuring many variables of ankle force and power production, DeVita acknowledges that it is actually the calf muscles – particularly the soleus and gastrocnemius muscles – that produce these forces. Since DeVita’s not a trained strength and conditioning coach, he hesitates to suggest exercises that could help runners maintain more ankle power. However, he noted that a combination of slow, heavy-weight strengthening workouts and faster, lower-weight power workouts for the lower leg should work well.
Of course, all new exercise regimens should be undertaken slowly and progressively. Unaccustomed ankle work could improve performance and injury-prevention, or could cause an injury, particularly in the case of aging runners who add something different to their routine. Devita understands this, noting, “One must be careful with any exercise, especially a new one. Anyone can overdo the amount of loading a tissue can take.”
The study authors were also impressed by the way the runners held their lean BMI through the decades.
“It appears that long-term running might be an effective non-pharmacologic weight maintenance intervention,” they wrote.