with Erik Lewish
Walking on two legs is a distinctly human activity. We are the only species since the dinosaurs to cover vast distances only by walking on two legs. From the time our early ancestors took their first steps about six million years ago, humans have expanded to every corner of the globe. So at first glance, you may think that walking (the very activity that defines our species) is the perfect way to strengthen our legs. However, while walking is a great aerobic activity and can help prevent muscle wasting in older adults, it doesn’t mean that you can skip leg day.
We primarily engage our Type I muscle fibers when we walk. These muscle fibers are smaller and more fatigue resistant than our stronger and more powerful Type II fibers. Since our Type II muscles are larger and stronger, they burn more calories when using them. Working our Type II muscle fibers helps to increase lean body mass which results in an increase in basal metabolic rate and more favorable body composition – a benefit we don’t achieve by walking alone. Also, when walking, we only move our joints performing the activity through a minimal range of motion. This can make things like walking upstairs, getting out of a chair, or getting down and up off of the floor feel harder since we are not used to working our muscles and joints in that way. Walking is mainly an aerobic activity and therefore doesn’t engage our anaerobic energy systems, meaning we lose our ability to create power through the legs. Less power means we can’t move our bodies quickly enough to keep our balance or catch ourselves to prevent a fall. Strength is directly tied to balance, as one improves, so does the other. Since walking is something we do every day, our bodies are very efficient at it, and therefore it doesn’t stress our muscles very much. We become habituated to it and burn fewer calories when performing the activity.
When we strength train, we engage both our Type I and Type II muscle fibers. Strength training generates a greater load on our bones, cartilage, ligaments, tendons, and muscles. It helps us to strengthen all of these tissues. Strengthening all of the tissues makes us more durable and resistant to injury. Strength training not only strengthens the peripheral tissues, but also strengthens our neural connection within the brain and at the neuromuscular junction. This can lead to greater movement efficiency, proprioception, motor unit recruitment, balance, and reaction time.
If walking is the only exercise you are using for your lower body, then you are leaving strength gains on the table. Talk to one of our coaches about how you can incorporate leg strengthening exercises into your workout regime; because you can’t spell legendary without “leg day."