Strong muscles aren’t just for lifting heavy things. Strength can benefit us in many ways, affecting different systems of the body. In physical therapy, we value strength because it helps keep us mobile and functional. We also appreciate it for its role in improving overall well being!
Muscle is a metabolically active tissue. In other words, our muscles store glucose (sugar) as a source of fuel. More muscle means more space for glucose storage, resulting in less glucose in the bloodstream. Our pancreas produces insulin, which is a hormone that lowers blood sugar. It helps the glucose enter the body’s cells so it can be used for energy. In some cases, these cells stop responding to the insulin (or require more insulin to do the job). This is called insulin resistance, and when left untreated, can turn into prediabetes or type 2 diabetes. Exercise and strength training can help improve the way insulin works to improve glucose metabolism and reduce the impact of sugar in our blood.
Strength training can also optimize other types of hormones in our body. It helps boost or balance out the levels of testosterone, estrogen, and progesterone. These sex hormones are different in men and women, and are critical throughout different times in our lives. Human growth hormone (HGH) helps promote fat burning metabolism, immunity, and muscle growth and is best activated with intense exercise and during REM sleep (sleep matters, too!). Strenuous exercise can also increase circulation of insulin like growth factor 1 (IGF-1), which helps repair tissue and promote bone and muscle growth. Intense exercise may not be indicated for everyone, so it is important to understand your current level of activity and/or consult with a health professional before starting any exercise programs.
Resistance exercise can decrease and/or prevent osteopenia (low bone density) and the development of osteoporosis (loss of bone integrity). Applying stress to our bones though weight bearing exercise and strength training helps activate osteoblasts (bone forming cells). Increasing muscle strength promotes stability and balance, which can further reduce our risk of falls and subsequent breaking of bones.
Don’t forget, our heart is a muscle too! Exercise is one of the best things we can do to reduce stroke and heart attacks. It helps to lower cholesterol and high blood pressure, and decrease risk of chronic disease. Are you getting enough exercise? The US Department of Health and Human Services recommends at least 2 days a week of muscle strengthening activity for adults. If you are not meeting the recommended requirements, no need to stress. Start small, and slowly increase to reap the benefits.
Quality of Life & Aging
Being strong also improves quality of life, especially as we age. Muscle mass starts to decline as we enter our 30s. Known as sarcopenia, this loss of muscle only worsens as we age. Those who are inactive can lose 3% to 8% of their muscle mass per decade. Unfortunately, if we don’t use it, we lose it, with the rate of decline increasing after age 60. Weakening of muscles increases risk of injury, and ultimately decreases level of function. Even more concerning is the rate of mortality and how it increases with sedentary behavior.
Lastly and equally as important is our mental health. Research by O’Connor, Herring and Caravalho (2010) summarizes evidence from randomized controlled trials to examine whether strength training influences factors related to mental health. They found that strength training alone helps reduce anxiety symptoms in healthy adults, but continued research needs to be done to determine effects on those with anxiety disorders. Within this study they also found that strength training can reduce pain intensity (among people with low back pain, osteoarthritis, and fibromyalgia) and has small to moderate improvements in cognition among older adults. There were also large reductions seen in depression symptoms. When compared with aerobic exercise (ex: cardio), strength training alone resulted in the largest improvement in fatigue.
No doubt about it, our strength will fluctuate throughout our lives. What motivates you? For some, it might be increasing self esteem about appearance. For others, mental health and improving quality of life are of most importance. Sometimes the biggest challenge is getting started. If you need help setting goals or just don’t know where to begin, the clinicians at Complete Physical Therapy are trained to help.