Have you ever wondered why fitness experts advocate for varied workouts that incorporate strength training? Is it because they enjoy causing you pain and seeing you so sore that you can barely get out of your seat? Well, that could be the case, depending on what fitness expert you follow and their level of sadism around their craft. But, more than likely, it’s because there is an understanding that strength and resistance training has huge health benefits, from increased calorie burn and cardiovascular benefits, to blood sugar management and bone health.
You may think of your bones as a static structure that gives you form and has very little change once you stop growing. In actuality, bones are dynamic organs in constant flux. This process is called bone remodeling. Osteoclasts are cells within the body that are constantly breaking down old bone, while osteoblasts, or cells that create new bone, are working in tandem. This equilibrium, or balance of bone health, can be modified based on stress, or lack of stress.
This idea of bone remodeling was first described by Dr. Julius Wolf in the 19th century. He showed how bones, responded, adapted, and ultimately remodeled based on the stress that was placed upon them. This became known as Wolf’s Law. In everyday life we see examples of this. Weightlifters have been shown to have higher bone density (1) and the opposite is seen in astronauts (2). Due to no gravity, they have been found to have decreased bone density upon arrival. It is something that also plays a large role in Orthopedics as we deal with bone health, fractures, and injury prevention.
How does resistance training help with bone health?
It’s best to think of bones and muscles as working as one functional unit. Without bones, muscles couldn’t function and without muscles we would be just a static skeleton. So, every time you start your resistance workouts on ARENA, you are stressing your muscles, which in turn is actually placing stress on your bones. Yes, every squat you do, helps you get ready for bikini season, but more importantly, each of those squats places force and loads through your back, hips, and leg bones causing them to respond to that stress and get stronger.
Do we need strong bones?
It seems like a silly question, but regular resistance training that strengthens bones can actually prevent fractures or broken bones. This is especially important as we age. Our bones become weaker with age, partly because the balance between breaking down and building up bone becomes less efficient, but also partly because most of us stop putting stress and loads through our bones. It’s just not as common to see gam-gam ripping squats and deadlifts in the gym, right? This combination of decreased biology and decreased stress leads to a situation called osteoporosis. Osteoporosis is a term we use that describes the density of our bones when they’re below a certain threshold. Think of young healthy bone as a cement brick and osteoporotic bone as a dried out sea sponge - very porous and brittle. As you can imagine, if your bone has lost its density, your likelihood of breaking a bone during a fall dramatically increases. Worldwide, osteoporosis causes more than 8.9 million fractures annually, resulting in an osteoporosis fracture every 3 seconds (3). So, although there are medications that address the biology aspect of osteoporosis, regular resistance training helps keep our bone density up and can help limit the risk of fragility fractures. I recommend resistance training to all my patients, regardless of age or ability level. I also believe that using the ARENA unit is actually more advantageous from a safety perspective as you can dial in the resistance by the pound, compared to traditional, more intimidating gym equipment.
What if you get injured?
So we can understand now how maintaining a balanced resistance training regimen can help prevent injury, but what happens if you are unlucky enough to sustain an injury? Well, Wolf’s Law also applies to rehabilitation and injury recovery. In the past, we used to cast and completely immobilize patients with fractures (think ‘comical full body cast’ image that you see in movies). We thought that broken bones needed complete rest to heal, and although there are definitely still situations where casting is appropriate, we learned that early mobilization and applying some gradual force through the fracture site can help with bone remodeling and healing. This is why physical therapy is paramount to helping injured patients work towards a full recovery. The same principles of bone remodeling and healing are at play with injury recovery, and having a professional gradually increase your resistance training and strengthening helps get you back to doing everything you want to do.
Take home points
- Your bones are dynamic organs in constant flux and respond to force i.e. Wolf’s Law
- Strength training is vital to maintaining bone health and helps in injury prevention
- ARENA is a great tool to help keep your workouts varied and safely add resistance training to maintain bone health
1 - Mayo Clinic Staff (2010). "Strength training: Get stronger, leaner, healthier". Mayo Foundation for Education and Medical Research. Archived from the original on September 22, 2012. Retrieved 19 October 2012.
3 - Johnell, O. and J.A. Kanis, An estimate of the worldwide prevalence and disability associated with osteoporotic fractures. Osteoporos Int, 2006. 17(12): p. 1726-33.