In one study, researchers discovered that as many as half of the runners who were either in the middle of a running a marathon or who had just completed the 26.2 mile distance exhibited temporary levels of chemicals in their system that promote inflammation and cardiac damage.  Furthermore, these elevations could last for several days.  If this occurs repetitively, it was found that these compounds can lead to scarring of the heart and its main arteries as well as to enlarged ventricles.  In turn, these effects can cause cardiac arrhythmias (irregular heartbeats) and sudden cardiac death.

Researchers suggest that athletes hold back intense exercise to about 60 minutes a day.  Workouts can be longer as long as the intensity is lowered or if these individuals have regular checkups with their physician who can monitor heart health.

It was suggested that beyond 30 to 60 minutes of exercise, there are diminishing benefits.  Also, at a certain point extended exercise may be harmful.

He goes on to explain some other ways to address biomechanical issues of the feet and some of the downsides of orthotics.

Twenty years ago, I was fitted for orthotics because I had a leg length discrepancy and pronated feet.  I wasn’t experiencing any orthopedic symptoms but it was supposed to be preventative for future expected problems.  A couple of years later, while studying feet during my Masters in Physical Therapy, the professor even commented on my feet which could not be centered between the two malleoli (ankle bones).  I wore orthotics for years, eventually losing one of them when I was asked to leave my shoes outside somewhere and one of the shoes (with the orthotic) disappeared, probably kidnapped by an animal missing a shoe, or needing orthotics.  I continued to wear the one orthotic because it happened to be the one for my shorter leg and provided some extra length to this limb.  About 10 years ago, I gave orthotics up for good without any repercussions.

I do think orthotics have their place in are needed in specific cases, but as Brian suggests, do consider other alternatives such as a better running shoe before spending the money on orthotics which are generally quite expensive.  Another option is to find a running coach or store and have your gait pattern analyzed with suggestions made on how to move in a more biomechanically safe manner.

While completing a degree in physical therapy in the early 1990s, we studied the foot quite extensively.  As part of the program, we explored all of its bones and muscles, some of the ligaments (as well as blood and nerve supply).   There are at least three layers of muscles. The foot is a work of art and it seems logical that we underuse its potential power by imprisoning them in supportive shoes. 

In the book, it was described this way:  “Just look at the architecture.  Blue print your feet, and you’ll find a marvel that engineers have been trying to match for centuries.  Your foot’s centerpiece is the arch, the greatest weight-bearing design ever created.  The beauty of any arch is the way it gets stronger under stress; the harder you push down, the tighter its parts mesh.  No stonemason worth his trowel would ever stick a support under an arch; push up from underneath, and you weaken the whole structure.  Buttressing the foot’s arch from all sides is a high-tensile web of twenty-six bones, thirty-three joints, twelve rubbery tendons, and eighteen muscles, all stretching and flexing like an earthquake-resistant suspension bridge. Putting your feet in shoes is similar to putting them in a plaster cast”.  

Basically, the foot’s job is to read the ground, react efficiently and effectively, with the body coordinating with it.  In a supportive shoe, blocked from both sides and below, the foot cannot move naturally.  In addition, with the many layers wedged between it and the ground, the surface cannot be accurately interpreted.  Consequently, the running form is altered, losing its efficiency, not only because of the changed running form, but also because the foot cannot contribute effectively.  Heelstriking, as explained in the book, is a phenomenon that arrived on the scene as shoes became more supportive.   Previously, midfoot and forefoot landing was the predominant form.

When I began running in the early 80s, I decided that a very supportive shoe was worth the money to protect my feet and my joints.  Little did I know that this might have been backwards thinking. 

In Born to Run, the author described studies that revealed that the more expensive the shoe, injury was 123% more probable compared to using lower quality less expensive shoes². Furthermore, the investigators determined that it was the price of the shoe, not the body weight, previous injury, running surface, speed nor weekly mileage that determined the rate of injury.   I found their results surprising, yet it made total sense, if you acknowledged the structure of the foot. 

As is described in the book, barefoot running isn’t something we convert to overnight.  Most of us have developed some really bad habits as time went on with our super supportive foot gear; also, our feet have become extremely weak and lazy.  If you consider making the transition, it would be best to start with very short distances e.g. ¼ mile, if that, and slowly allowing your foot and the remainder your structure to adapt with time. Careful attention must be taken to body alignment.  If something is hurting e.g. the joints, muscles (strain), ligament or bone, back off, try to correct the problem or even consider getting a coach or taking a running workshop where techniques are taught; in the book, they refer to three possible options: ChiRunning, Pose Running and Evolution Running.  

For more information, you can go online and google “Barefoot Running”.  The book is a good place to start too.  It may not be possible for everyone to get down to the barefoot level.  There is a shoe out described by McDougall called the Vibram Fivefingers, offered in both men and women’s sizes, which is like a sleeve with a thin sole serving as a protective layer between the foot and the ground.  According to the book, only 25% of people that attempt the transition to barefoot running succeed.  I think, for most people including myself, simply moving towards a less supportive shoe, might be more realistic and a safer way to go.  Ultimately, whichever path you choose, very supportive shoe vs. barefoot or something in between, injury-free running and the joy of running are the important goals.  It’s not worth running barefoot if your body won’t adapt safely. 

Resources:

 1. Born to Run by Christopher McDougall 

2. The American Journal of Sports Medicine (1989), study by Bernard Marti, MD

One day after it had snowed a couple of inches overnight, I decided to enjoy a rare opportunity of running on the whitened paths of  my town.  The snow drew more people outside on this weekend day than normally.  A few of them were strolling carefully around the neighborhood, while others were shoveling.  Many kids (and adults) were frolicking in the snow as well.  Everyone appeared cheery and seemed to be enjoying the break from chronic clouds and rainy weather. 

Having lived in the Canadian and American Northeast for over thirty years before moving out here, I had learned how to tread on ice and snow.  However, because I was out of practice and because it was just the safe thing to do, I began running very gingerly.  I ran on roads and sidewalks on both snow and dry surfaces.  As I progressed through the neighborhood, I was amazed to discover that it was easier and more fluid to run on the snow than directly on the dry areas.  Consequently, when I had a choice, I navigated myself onto the snowier sections.  At the time, I had no understanding why running on snow was easier. 

A few years later, after completing the ChiRunning Instructor training, I reasoned why it had been easier to run on the snow that day.  While running directly on the cement or asphalt, I had pushed off with my legs.  However, on the slicker snowy surfaces, my foot slid back and then lifted off the ground.  It took much more energy to “push off” rather than “glide and lift”.  Unconsciously, I must also have been leaning to allow gravity to pull me forward;  I couldn’t have pushed off or I would have fallen “splat” on my face. 

That snowy day, I had not gone running.  I had gone gliding!

(NOTE: If you are prudent, snow can be an excellent place to practice ChiRunning;  your feet do not glide back on non-snow surfaces, but they do stay in contact with the ground as you move forward.  At end range, the foot lifts off, rather than pushes off, the ground.  When running on the snow,  I would  caution that you pay extra attention on the slippery surface and avoid ice when possible.  Also, I suggest that you leave plenty of room between yourself and cars so that drivers have more space to maneuver if they lose control of their vehicles.)

It brought me out of my reverie and I wonder in surprise (and annoyance), “Why on earth did I just do that?”  My goal was two miles, nothing less.  I contemplated turning around again and officially completing the first leg of the run.  I decided not to as I had momentum in the new direction and decided, “Oh well”. 

At the base of the main hill is a cul-de-sac with a sidewalk surrounding the road end, then a high wooden fence with an opening allowing access to pedestrians.  Once through this doorway lies a wide sidewalk, followed by the street if you keep heading forward.  The moment I went through the opening, I glanced to my right and to my horror, a car was traveling along the sidewalk towards me.  The woman driving threw her hands up off the steering wheel in shock as I stepped into her pathway.  I couldn’t accelerate, decelerate or stop.  To my relief (and I’m sure the driver’s), the car didn’t hit me. 

I was angry after the near miss.  I considered sprinting to this woman who had parked at some mailboxes about thirty feet to my left.  I certainly had a few words for her, but I knew I was too angry to have a calm discussion.  I rationalized that she was now educated about the danger of driving against the traffic along the sidewalk!  I hoped that she would never do it again.  She had seemed genuinely startled when I stepped out onto the walkway. 

Later, when I relived the incident in my mind, I realized that just shy of the half-way point, a force seemed to have turned me around.  I remembered a similar experience during a situation a few years previously in South Dakota; while on a country road in the dark, I was returning to the campsite where I was staying.  I feared missing the entrance by ten or twenty miles and then driving up and down the road all night.  So, I asked the Universe to direct me to the entrance.  Many miles later, as if on cue, the steering wheel suddenly rotated left.  Relieved, I had reached my destination. 

The steering-wheel-turning sensation on the country road was similar to what I experienced on the run that day: a sudden, forceful, swift movement, yet smooth and precise.  It would have been impossible to counteract this power had I attempted to and besides, it was over before I could react.  Had the run not been cut short by a few seconds (placing me ahead of schedule), I concluded that I would have been nailed by that car.  Had some protective force participated?  I’d like to believe so.

http://sportsmedicine.about.com/cs/strengthening/a/030904.htm

http://www.shapefit.com/target-heart-rate-zone-vs-perceived-exertion.html