Muscle Mass and Longevity
There are innumerable recommendations regarding the achievement of longevity. The treatments vary from supplements, lifestyle changes, and hormonal therapies. Many of these recommendations involve some degree of adjustment in our daily lives. Willpower is an essential ingredient if some of these recommendations can be achieved.
Muscle mass measures the amount of muscle in our skeletal system. It is well-known that the magnitude of muscle mass correlates with long-term survival. Unfortunately, there is a progressive decline in the degree of muscle mass as we all age. There is an approximate 3% loss in muscle mass for each decade of life after our third decade. There are very effective ways of slowing or even reversing this process. Still, understanding the importance of muscle mass in our struggle for longevity is also essential to describe.
Most older individuals know their strength tends to wane as they age gradually. This deterioration is attributable to a variety of different things. However, the underlying factor is loss of muscle mass and strength resulting from activity limitations, drop in circulating hormone levels, and poor dietary habits that overemphasize simple carbohydrates and processed foods.
Testosterone is a critical hormone for overall muscle adaption and growth. Testosterone is formed from cholesterol and is converted to estrogen by an enzyme called aromatase. Testosterone levels are significantly higher in men when compared to women, but testosterone plays a vital role for both men and women.
Lean muscle mass is a predictor of metabolic health. Muscles are one of the primary utilizers of glucose, and adequate muscle mass allows our body to optimize ingested glucose. Testosterone also affects sexual health. Testosterone is also broken down to estrogen by an enzyme aromatase. Estrogen plays a significant role in reducing the risk of osteoporosis as we age, and declining levels of testosterone in men and women are linked to lower estrogen levels.
One of the most effective ways to increase testosterone production is exercise. Weightlifting can significantly elevate testosterone levels long-term and improve lean muscle mass. One can see that stimulating testosterone production can substantially benefit metabolic health. The presence of adequate muscle mass will help to mollify excess glucose ingestion. An increase in overall protein intake can also lead to enhanced muscle mass. Interestingly, sexual intimacy can also serve to increase testosterone levels, but the most remarkable production increase in testosterone occurs with exercise.
One of the concerns regarding statin therapy is that a reduction in cholesterol may lead to a decrease in the production of both testosterone and estrogen. Enhance muscle mass independently while on statin therapy may be somewhat blunted in the presence of statins. This group of drugs also causes muscle weakness and more muscle soreness after exercise in many patients. There is also evidence that statin use reduces handgrip strength and walking speed in patients with underlying heart muscle weakness.
It is well known that weight-bearing exercise and weightlifting are two of the most effective ways to lower the risk of osteoporosis. I have always encouraged my older patients to engage in these activities. Adding vitamin D3 to this exercise regimen can significantly offset osteoporosis risk. Aromatase activity is increased in the presence of obesity and with advancing age. This may serve, to some extent, to lower the risk of osteoporosis. On the other hand, declining levels of testosterone tend to offset any benefit of increased aromatase activity. As a result, estrogen production in men and women can further diminish over time and can enhance the risk for osteoporosis.
As we age, we tend to spend less time in physical activity. In addition, we spend more time indoors and tend to gain weight if our calorie intake does not diminish. Many people consume more carbohydrates than protein as they age. This decrease in overall protein ingestion will also lead to a reduction in muscle generation. Therefore, it is not hard to understand that the combination of less activity, less vitamin D production due to diminished sunlight exposure, diminished protein intake, and diminished weightlifting will all lead to progressive frailty. Andro-menopause is a term that describes this condition, where testosterone reduction leads to metabolic illness and frailty.
To overcome these detrimental effects of aging, I would recommend the following:
- Begin a regular weightlifting program at least 2-3 days a week. A 30-45 minute session should be adequate. Heavy weightlifting is not necessary. Lighter weights that are lifted more frequently can achieve the same benefits of enhancing muscle mass. In addition, this technique may also have the best effect to elevate testosterone levels.
- Perform regular aerobic exercise at least 4-5 days a week. Weight-bearing exercises such as walking, jogging, or racket sports can be an ideal way to reduce osteoporosis risk.
- Spend as much as much time outdoors as possible. It is vital to have some sun protection during certain parts of the year, but early morning sunlight can significantly benefit melatonin and vitamin D production.
- Increase overall dietary protein intake to achieve 1-2 g per kilogram of weight. For a typical 70 kg man, this would mean a total protein intake of approximately 100-140 g per day. A reduction in overall carbohydrate intake should occur as protein intake increases. In those patients with underlying kidney disease, a discussion with your primary care physician will be necessary before making any protein intake adjustments.
- Attempt to limit alcohol as you age. Alcohol is frequently a source of unnecessary carbohydrates. In addition, frequent use of alcohol may serve as a demotivator for activity. Alcohol also enhances aromatase activity and may serve to lower testosterone levels while increasing estrogen in men. This can lead to prominent breast tissue and increased abdominal fat.
There has been an increase in interest in testosterone replacement therapy in older individuals. Although this may be slightly effective in those men and women who have significant issues with testosterone production, the overall benefits appear to be very limited. In addition, there are some risks associated with excess testosterone supplementation. In those individuals who have low testosterone availability, it is worthwhile to review lifestyle habits and medications to determine if there is any underlying cause of the low testosterone levels. I always believe that a 3-6 month trial of lifestyle modification that includes weightlifting, exercise, dietary adjustment, and alcohol reduction is much more fruitful in achieving improved testosterone levels.
Another important consideration that needs to be discussed is the role of carbohydrates and its negative effect on muscle mass. An increase in carbohydrate intake is frequently associated with increased muscle fat deposition. In layperson’s terms, one turns their muscle from a filet into a ribeye. The increase in fat deposition can significantly impact overall strength and frequently leads to insulin resistance. The development of insulin resistance is most pronounced in both skeletal muscle and the liver. The development of diabetes is a frequent result of prolonged insulin resistance and can further contribute to the loss of muscle mass.
Nevertheless, aggressive lifestyle changes can have significant positive results. Muscle mass and strength improvements are not limited to younger adults. Evidence shows muscle mass and functional stability can be enhanced well into the eighth decade with resistance weight training.
Overall, what we desire most often requires the work we want the least. Regular weightlifting and aerobic exercise that is coupled with healthy dietary habits, can play a significant role in prolonging health and happiness. Just like most things in life, the results will be self-evident if we put in the work. On the contrary, we must understand the consequences of our unwillingness to change or put forth the required effort as we age. Aging can be a beautiful and remarkably satisfying time. We must all endeavor to care for ourselves so that we can care for others.