WHEN does a walk turn into a jog? And a jog turn into a run?
The activities of walking, jogging and running are similar, but are technically differentiated by relative speed and the ground contact with the feet. For example, relative speed simply means that an individual’s jog is faster than a walk, and a run is faster than a jog. But speed is only half the equation.
A walk turns into a jog when the speed reaches a velocity that causes only one foot at a time to make contact with the ground. When both feet are on the ground, the activity is technically a walk. Jogging turns into running when the activity reaches a velocity that can cause both feet to be momentarily in the air and only one foot at a time contacts the ground for landing and propelling the body forward.
But are the activities of walking, jogging and running the same kind of acts on a treadmill as they are on the street? There are many mechanical and physiological similarities, but as the speed increases on the treadmill, jogging and running mechanics become very different than being on the street. Let me explain.
Walking, jogging and running challenge your cardiovascular system no matter what surface you are on. You can get your heart rate and breathing to elevate on both the streets and the treadmill. The faster you go, the more your metabolism increases and more the calories consumed.
The mechanism of being on the treadmill versus being on the street is perhaps the biggest difference between the two surfaces. This is probably the most important matter to the individual who has an injury or movement dysfunction that could later lead to an injury. At lower speeds, the treadmill and the streets induce a gait pattern that is similar in mechanics. A gait cycle can be broken down into many components, but generally into three phases — the initial contact (heel strike), the load (mid-stance), and finally the toe-off.
As speed increases, the amount of foot contact with the surface reduces, and the percussive forces on the foot and ankle gradually transfer into the knee, hip and spine. On the treadmill, speed is non-negotiable! Your body must keep pace with the machine or you wind up on the floor (check YouTube for “treadmill fails”). Even if you are able to keep pace with the treadmill’s speed, you are forced to maintain a gait pattern or form that is dictated by the movement of the belt. Your foot strike, mid-stance and toe-off are propelled by a moving surface and must therefore conform to its speed. Once again, this may not be a problem if your form and the machine speed are compatible, but at some point, either your fatigue or your ability may be challenged by a moving surface that will never conform to you — only you to it.
On the street, all speeds of walking, jogging and running are determined by the individual rather than a machine. Foot strike, mid-stance and toe-off mechanics are subject to change from stride to stride, and the individual has an ability to manipulate the speed and tempo of the gait cycle in real time, depending on pain levels, fatigue or obstacles along the path.
The amount of impact on the ankles and knees can also be reduced on the streets by choosing a more favorable terrain such as dirt or grass, and frequent changes in surfaces keep the nervous system alert and adapting to the activity. The smooth surface of a treadmill might not be challenging for jogging and running for some, but provides a predictable surface for those struggling with foot dysfunction or difficulty balancing.
Last but not least, running on the treadmill is confined. The bars on the sides, the length of the belt and the control center together create boundaries that could limit arm swing and stride. Running mechanics are highly individualized between people, and boundaries around your natural running style can encourage movement dysfunction rather than correct them.
Walking, jogging and running are great ways to exercise. But weigh out the benefits versus the risk of being on a machine and being on the street. Even though I personally prefer to be on the streets, for some, being on the treadmill may serve a better purpose and reduce the risk of falling.
Whether you choose to be on the streets or on the machine, remember to change up your speed, distance or both in order to keep yourself challenged. Focus on good form no matter the speed, and make sure you stretch before and after your activity. Happy trails!
Dr. Adrian Pujayana has been providing drug-free solutions for health and wellness to adults, athletes and youth since 2000 through his private practice at Family Chiropractic Center of South Pasadena, a place for strength training and nutrition-based health care. For comments or questions, email him at firstname.lastname@example.org.