I have been running for nearly 40 years. It is my primary form of exercise unless weather conditions dictate that I exercise indoors. Then I go for my Precor 546 elliptical trainer. I used to be much hardier when I was younger and used to run outside no matter what the condition. Now I will rarely run outside if the temperature is below freezing, if it is dark or if it is raining. I have broken a number of bones in my life by running in "unsafe" condtions and I have read of too many people being killed because they were hit by a car at night, so I now chose safer condtions.

Another reason I find running so useful is that it is highly efficient and I can maximize my time efficiency with it. I also happened to be reasonably good at it when I was younger and have run a 2:50 marathon when I was in medical school and on the University of Chicago Track Club.

However, it is important to understand that just because I find running personally useful that does not mean most people should do it. Quite the contrary. In fact nearly anyone with a knee injury is asking for trouble if they choose running as their primary exercise. Additionally, obese individuals typically have higher risks of injury with running so elliptical trainers are a far better option.

I found this article on how running differentiates us from the apes quite fascinating and thought many would enjoy it.

Some Anatomical Features That Help Humans Run

• Skull features that help prevent overheating during running. As sweat evaporates from the scalp, forehead and face, the evaporation cools blood draining from the head. Veins carrying that cooled blood pass near the carotid arteries, thus helping cool blood flowing through the carotids to the brain.

• A ligament that runs from the back of the skull and neck down to the thoracic vertebrae, and acts as a shock absorber and helps the arms and shoulders counterbalance the head during running.

• The tall human body - with a narrow trunk, waist and pelvis - creates more skin surface for our size, permitting greater cooling during running. It also lets the upper and lower body move independently which allows you to use your upper body to counteract the twisting forces from your swinging legs.

• Shorter forearms in humans make it easier for the upper body to counterbalance the lower body during running. They also reduce the amount of muscle power needed to keep the arms flexed when running.

• Larger surface areas in the hip, knee and ankle joints, for improved shock absorption during running by spreading out the forces.

• The arrangement of bones in the human foot creates a stable or stiff arch that makes the whole foot more rigid, so the human runner can push off the ground more efficiently and utilize ligaments on the bottom of the feet as springs.

• Humans also evolved with an enlarged heel bone for better shock absorption, as well as shorter toes and a big toe that is fully drawn in toward the other toes for better pushing off during running.

Medi Lexicon November 18, 2004