Earlier this year I joined a running club, Steel City Road Runners (come run with us!). I’m still a newbie, but I really enjoy the challenge that running provides. This past week, the Boston Marathon announced to applicants who would be awarded the last 5,000 spots in the 2014 Boston Marathon. It was really inspiring to see many of the people in my group be awarded these spots, I know how hard they have worked, and I’ve pounded the pavement with them more than once.
Long distance running is a physical and mental challenge. But being the bioengineer that I am, I can’t help but think about the biomechanics of running. It is mind blowing to me that the human body can handle repetitive loads on the joints, 10x the weight of the body, and still work just fine after 80 or 90 years of life.
I’ll run some numbers for you, to show you just how impressive the body is. A normal running cadence is about 180 steps per minute. At that rate, if you ran a 4 hour marathon, you would be taking about 43,200 steps. Considering many athletes need to train for 20 weeks at about 30 miles per week, you can tack on another million steps or so. Over the life of a long distance runner, it’s not unreasonable to think that their joints would experience billions of cycles of load.
Amazingly, the body is completely capable of handling this repetitive motion. If injuries do occur many of them can be resolved with proper rest and stretching. Technology has advanced so much over the past 50 years, and luckily, medical device companies are able to offer products such as artificial knees (like Zimmer's NexGen mobile bearing system) and hips (like Stryker's patented X3 Technology) if ours do fail. But like all things mechanical, they eventually wear out over time. The human body is a very special type of machine, and researchers and companies all over the world are spending lots of time and money trying to decipher what makes it work so well. Technology can only get better from here, and maybe someday we will have an artificial knee that will last for 50 or 60 years.
Next time you go out and pound the pavement, take a minute to appreciate the biomechanic capabilities of the human body.