Running Injuries: The 10% Rule

I couldn't help but notice the relatively high incidence of knee pains and other running injuries among friends and on the SGRunners forum.

Not unlike many others, my enthusiasm led to my first injury - a very painful case of plantar fasciitis (PF). I could not even walk. I woke up at night with excruciating pain in my right foot. That episode taught me an important lesson: If I want to run for life, then I have to make it my goal to run injury free (after all I am "old bones").

After some research and through personal experience, I came to marvel at the adaptability of the human body. Put the body to stress, and it responds. Run longer distances, and the body adapts and becomes stronger. The next time round, it will be easier to cover the same distance. What a wonderful body God has given us.

While the cardiovascular system is amazingly adept at adapting, the musculoskeletal system takes more time. Which is why most running injuries affect the musculoskeletal system such as muscles, joints and bones. We need to give time for our muscles and bones to adjust to impact exercises. Then there is the question of age - wear and tear.

With further reading, I discovered the 10% rule. The rule is simply to increase mileage or intensity no more than 10% per week. So if my base mileage is 20km a week, increase mileage no more than 2km next week. This is slow progress especially in our day and age of instant gratification. But the 10% rule begets patience and most importantly, it helps avoid injury.

In addition, I schedule a recovery week every fourth week, where I cut mileage by 20 to 30%, simply to allow the body to be stronger. Interestingly, our bodies become stronger during recovery or rest, not during the run. Recovery is more important than we think. KHW, our deca-ironman tells me that he builds in recovery into all his cycles. There are cycles in his training by day, week, throughout the year and over years as well!

So I constantly remind myself to respect the 10% rule, run slowly downhill and (I don't really need to remind myself) to enjoy the rest days and recovery weeks! :)