Our bodies undergo various changes as we age, impacting our physical strength and overall health. The loss of muscle and the loss of strength are two important changes that we need to counteract. While these changes might seem inevitable, a powerful tool at our disposal can significantly mitigate their effects: resistance training. Often overshadowed by cardio exercises in popular fitness culture, resistance training is crucial, especially for older adults. It goes beyond just enhancing muscle mass and strength; it’s about preserving functional independence, maintaining metabolic health, and improving quality of life. This article delves into the multifaceted benefits of resistance training, addressing common misconceptions and highlighting its essential role in healthy aging.
What is Sarcopenia?
Sarcopenia, derived from the Greek words “sarx” (flesh) and “penia” (loss), refers to the age-related loss of muscle mass and strength. It’s a condition that typically begins to manifest around the age of 40 and accelerates after the age of 60. However, its onset and progression can vary greatly among individuals.
This decline in muscle tissue is more than just a cosmetic concern. Sarcopenia significantly affects an individual’s functional capacity, making everyday activities increasingly difficult. It’s associated with a higher risk of falls, frailty, metabolic diseases, and loss of independence among older adults. Despite its prevalence, sarcopenia often goes unrecognized in its early stages.
Muscle mass decreases approximately 3-8% per decade after age 40, and this rate of decline is even faster after 60. This condition results from natural aging, a sedentary lifestyle, the chronic inflammatory burden associated with non-communicable diseases like insulin resistance, and poor nutrition.
Understanding sarcopenia and its downstream effects is the first step in recognizing the crucial role resistance training plays in combating this age-related muscle loss. By actively working to maintain and build muscle tissue, older adults can significantly improve their overall health and quality of life. But… to be an active 80-year-old, we must start planning for that in our 50s and 60s.
Age-Related Muscle Loss
As we age, our bodies naturally begin to lose muscle mass and strength, a process that is more than an inevitable mark of aging but also a consequence of lifestyle choices.
Several factors contribute to age-related muscle loss:
- Hormonal Changes: Aging leads to alterations in hormone levels, including decreases in growth hormone, testosterone, and estrogen, which play significant roles in muscle maintenance and repair.
- Reduced Physical Activity: With age, as well as our busy modern lifestyle, there’s often a decrease in physical activity, leading to a use-it-or-lose-it scenario where muscle fibers are not stimulated enough to maintain their size and strength. Evolutionary pressures can be mean.
- Nutritional Deficiencies: Older adults are more susceptible to nutritional deficiencies due to reduced food intake or less efficient nutrient absorption. Protein intake, in particular, is crucial for muscle preservation.
- Neuromuscular Changes: Aging affects the nerves responsible for stimulating muscles, which can decrease muscle mass and strength because of the loss of recruitment of the muscles that have lost the ability to communicate with the brain. The nerves to the muscles lose their attachment and, therefore, their ability to communicate with the muscles.
Microscopic Changes in Muscles
At the microscopic level, age-related muscle loss involves significant changes within the muscle tissues:
- Loss of Type 2 Muscle Fibers: These fast-twitch fibers are crucial for power and strength. With aging, there’s a notable reduction in their number and size, contributing to decreased muscle strength and agility.
- Reduction in Satellite Cells: Satellite cells are essential for muscle growth and repair. Aging decreases their number and functionality, hindering the muscle’s ability to recover and rebuild after injuries, disuse, or exercise.
- Decreased Muscle Protein Synthesis: The ability of muscles to synthesize protein diminishes with age, affecting muscle maintenance and growth. This decline is partly due to reduced responsiveness to protein intake, known as anabolic resistance.
- Decrease in motor end plates… these are the structures through which nerves terminate onto muscle to facilitate communication with the brain.
Metabolic Consequences of Muscle Loss
The loss of muscle mass with age, a core aspect of sarcopenia, has far-reaching metabolic consequences:
- Insulin Resistance: Muscle is a key tissue in glucose metabolism. Reducing muscle mass impairs the body’s ability to regulate blood sugar levels, increasing the risk of insulin resistance and type 2 diabetes.
- Increased Body Fat: As muscle mass decreases, metabolic rate slows down, and insulin resistance worsens, it leads to further accumulation of body fat.
- Risk of Metabolic Syndrome: The combination of increased fat, especially visceral (belly) fat, and reduced muscle mass contributes to the risk of metabolic syndrome, characterized by a cluster of conditions like hypertension, high blood sugar, and abnormal cholesterol levels.
- Inflammation: Sarcopenia is often associated with chronic low-grade inflammation, which can exacerbate the loss of muscle mass and contribute to further metabolic disturbances.
Dispelling Myths About Building Muscle in Older Age
A common myth is that seniors cannot effectively build muscle, but research led by experts like Dr. Stuart Phillips dispels this notion. Studies show that even in their 60s, 70s, and beyond, individuals can significantly increase muscle mass through resistance training.
Dr. Phillips’ research highlights that while older adults may face challenges like anabolic resistance (reduced muscle-building response to protein intake and resistance exercise), they can still make substantial gains in muscle strength and size. His work emphasizes the importance of tailored resistance training programs and adequate protein intake to overcome these challenges.
This research not only counters the misconception that muscle building is futile in later years but also motivates older adults to engage in resistance training as a viable way to enhance muscle mass and overall health.
Anabolic Resistance and Aging
Anabolic resistance is a key factor in age-related muscle loss. As we age, our muscles become less responsive to protein intake and resistance exercise, making building and maintaining muscle mass more challenging. This resistance is partly due to changes in hormone levels, reduced muscle protein synthesis, and alterations in cellular signaling pathways.
Despite these challenges, it’s important to recognize that specific strategies can mitigate anabolic resistance to a certain degree. But we cannot overcome evolution. So, anabolic resistance will persist as we age. These include engaging in regular resistance training, which can help to sensitize muscle cells to protein and enhance muscle growth signals, and ensuring adequate dietary protein intake to stimulate muscle protein synthesis.
Understanding and addressing anabolic resistance is crucial for effective muscle maintenance and growth in older adults, reinforcing the importance of a targeted approach to diet and exercise in combating age-related muscle decline.
The Risks of Inactivity vs. Weight Training
It bothers me to no end to hear from friends that the reason that they do not workout is the fear of injury. The comparison between the risks of inactivity and those associated with weight training is stark, especially for older adults.
Risks of Inactivity:
- Muscle Atrophy and Sarcopenia: Inactivity accelerates muscle loss, leading to weakness and increased frailty.
- Metabolic Disorders: A sedentary lifestyle contributes to obesity, insulin resistance, and metabolic syndrome.
- Cardiovascular Diseases: Lack of physical activity is a risk factor for heart disease and stroke.
- Decrease in VO2 max
- Bone Density Loss: Inactivity can decrease bone density, increasing the risk of fractures.
Risks of Weight Training:
- Injury Risks: There’s a perception that weight training, especially in older adults, carries a high risk of injury. However, the benefits far outweigh the risks when done correctly, under guidance, and with appropriate intensity.
- Overexertion: Another concern is overexertion, which can be mitigated by proper technique and gradual progression.
When considering whether or not to participate in a resistance training regimen, it’s clear that:
- Inactivity threatens health and quality of life in older adults more than the risks associated with weight training.
- With appropriate precautions and training regimens, weight training can be a safe and highly beneficial activity for older individuals, improving health outcomes and reducing the risk of chronic diseases.
Suggested Bodyweight Exercises
For older adults, particularly those new to resistance training, bodyweight exercises are an excellent starting point. They offer a safe and effective way to build muscle, improve balance, and increase functional strength. Here are some suggested exercises that can be performed three times a week:
- Squats: Great for leg and core strength. Start with chair squats if necessary, gradually progressing to standard squats.
- Wall Push-ups: A gentler version of traditional push-ups, focusing on upper body strength. As strength improves, transition to knee push-ups or standard push-ups.
- Lunges: Enhance leg strength and balance. Begin with small steps and progress to deeper lunges.
- Step-ups: Use a low step or platform. This exercise helps with leg strength and balance.
- Planks: Start with a half-plank (on knees) to build core strength, then progress to full planks.
- Leg Raises: Lying on your side, lift your leg to strengthen hip and thigh muscles.
- Bird-Dog: On all fours, extend opposite arm and leg, focusing on balance and core stability.
Sarcopenia is a cruel process. But if we want to remain healthy, active, fit, cognitively intact, and functionally independent, we must find a way to prioritize strength training.