running“More bad news for aerobic activity. Whether it’s running, cycling or a step class, the main reason it gets easier the more you do it, is not because of improved cardiovascular conditioning, but because of improved economy of motion. For the most part, it doesn’t get easier because of muscular endurance, but because your body is becoming more efficient at that particular movement. You require less strength and oxygen than you did before, because your body’s nervous system is adapting. Wasted movements are eliminated, necessary movements are refined, and muscles that don’t need to be tensed are relaxed and eventually atrophied. This is why marathon runners will huff and puff if they cycle for the first time in years.

Aerobic training actually causes muscle wasting because the body is programmed to adapt to whatever demands we place on it. Long low-intensity aerobic training only requires the smallest and weakest, “slow-twitch” muscle fibers to fire off again and again. The other, stronger and larger, “fast-twitch muscle fibers are not necessary for the task and become a burden to carry and supply with oxygen. The body has no demand for extra muscle beyond what is needed to perform a relatively easy movement over and over. So your body adapts by actually burning muscle. Even if you perform steady state training in conjunction with strength training, it will diminish any potential increase in lean body mass, especially in your legs. Aerobic training should only be used to develop movement proficiency when you are training for a specific sport or event, such as a 5k run, triathlon, or particular military fitness assessment.”

-pages 12-13 from the book “You Are Your Own Gym” by Mark Lauren, 2011 Ballantine Books

I have been thinking about the above entry by Mr. Lauren for some time now: self-reflecting on whether or not I have been following the “right” exercise program. I, myself, am a runner. I currently employ running during my “off” strength training days to keep my body moving. I was always under the impression that aerobic exercise was good for you…that it burned calories, increased circulation, expelled toxins, and made your muscles (primarily the legs, core, and arms) more muscular and toned. Did I ever feel as though running could be damaging my muscles, making them smaller, or even threatening to put surrounding-larger “fast-twitch” muscles in a state of atrophy? No, no and no. I started to look at different types of people and the exercise they did. At one extreme is someone relying solely on cardiovascular exercise, such as a long distance runner. The body type of this person is usually skinny, without much muscle. This would tend to defend the above author’s viewpoint. On the other extreme is a person who relies solely on strength training, such as a bodybuilder. They have great strength, but lack endurance and flexibility. In the middle we have a blend of cardiovascular and strength training utilized by someone such as sprinter or dancer. They tend to have the best of both worlds; muscular strength and the ability to use their muscles over a long period of time.

So, what is the answer? Should people run or not run? Mr. Lauren listed reasons why prolonged running isn’t such a good thing, but are there any advantages or benefits to it? Running makes people sweat, and this in turn releases toxins and increases circulation. Running also has psychological and emotional benefits. It increases confidence, relieves stress, and helps diminish depression. Unfortunately for running enthusiasts, these same benefits can be found in strength training at an increased pace, intensity, and duration to keep heart rate up. Additionally, the added resistance to muscles through strength training creates hypertrophy, which is not typically found in cardiovascular exercise.

But does running burn more calories? During my run, I feel as though I am constantly sweating and putting my body under tension. Does this necessarily translate into numerous burned calories?  According to the website, “…a 180-pound person will burn about 1,422 calories running 10 miles. But a lighter 125-pound person will burn just 988 calories in 10 miles. A heavier 230-pound person will burn 1,817 calories running 10 miles…” Considering one pound of fat is equal to roughly 3500 calories, the above scenario translates to a decrease in 1/3 to ½ pound of body fat per every ten miles run. This may seem like a lot of effort for a small return. So does strength training burn more calories?

According to Mr. Lauren, “During low-intensity aerobic exercise, fat oxidization occurs while exercising and stops upon completion. During high-intensity exercise your body oxidizes carbs for energy, not fat. Then, for a long time afterward, fat oxidization takes place to return systems to normal: to restore depleted carbohydrates, creatine phosphate, ATP (adenosine triphosphate), circulatory hormones, re-oxygenate the blood, decrease body temperature, ventilation and heart rate. Not to mention the longer term demands: strengthening tendons and ligaments, increasing bone density, forming new capillaries, motor skill adaptation, repairing muscle tissue and building new muscle. And the more muscle mass you have, the more calories you are able to burn during and after exercise.”

My personal answer to this article’s question is “yes”. Run, but at higher intensity, with more resistance, at shorter distances. I believe that common ground can be found between cardiovascular exercise and resistance training, and that a hybrid of the two can reap the benefits of both. I know there will be advocates out there that may disagree, standing by running as a viable form of fitness exercise.  I do feel that there are benefits to distance running, but unfortunately hypertrophy and burning significant calories are not some of them. Obviously one glove does not fit all in regards to fitness programming. Distance running may indeed be a perfect fit for someone. The key is making informed decisions on an exercise program that will help you reach your personal fitness goals.

About the Author

Christopher Kazda is a Certified Personal Trainer and a Chiropractic Technician at New Beginnings Chiropractic, 1861 Business Hwy 18/151, Mount Horeb, WI 53572. He is available Monday through Saturday to help you reach your fitness goals.

Please call 715-302-2153 or 608-437-9990, email at, or visit, for more information or to schedule an appointment.