Frailty: it’s a word no one wants to associate with aging. But what exactly causes older adults to become frail, and when does this process begin? More importantly, is it possible to prevent or even reverse it? The truth is, that frailty isn’t an inevitable part of aging. Understanding the underlying mechanisms, particularly the critical role of muscle strength, is key to breaking the cycle and maintaining vitality throughout life.
Muscle strength is far more than just aesthetics. Our muscles are the engine of our movement, enabling us to perform everyday tasks with ease. However, beginning around age 30, physically inactive individuals start experiencing a gradual decline in muscle mass—a process known as sarcopenia. This loss, typically between 3-5% per decade, accelerates significantly between the ages of 65 and 75. Sarcopenia isn’t just about losing physical prowess; it’s a primary driver of falls and injuries in older adults, often the initial push into the dangerous frailty cycle.
The impact of diminishing muscle mass on mobility is profound. Simple daily activities we often take for granted, like lifting an object from a shelf, shovelling snow, or climbing stairs, become increasingly challenging. This decline in physical capacity can have a cascading effect. As sarcopenia progresses, we naturally slow down, becoming less active. We walk slower, avoid activities that require exertion, and gradually withdraw from physical engagement.
This decreased activity has a detrimental impact on our cardiovascular system. A healthy heart and lungs depend on consistent physical activity. When sarcopenia leads to reduced movement, our cardiovascular system suffers, further accelerating the frailty cycle. It’s a vicious circle: muscle loss leads to decreased activity, which weakens the cardiovascular system, further limiting activity, and ultimately exacerbating muscle loss.
In addition to an impaired cardiovascular system, less physical activity inevitably leads to Dynapenia – a loss of muscle strength. So, a loss of muscle mass leads to a gradual decline in physical activity, which leads to a weakened heart and lungs, causing us to move even less and lose strength in the muscles we have left. This is the cycle of frailty and it carries an increased risk of falls, accidents and injury, hospitalization, and mortality.
Regardless of Age, Resistance Training is a Good Place to Start
In a perfect world, every 30-year-old would begin a resistance training program that they would maintain for the rest of their lives, staving off Sarcopenia and keeping a firm distance from the cycle of frailty. In the real world, we know this isn’t always the case. For some people, a concern about their health might prompt them to begin an exercise program as a preventative measure. For others, injury or illness motivates them to pay closer attention to their physical health requirements.
Regardless of the current state of health, strength, and mobility, resistance training is an excellent place to start. We know that progressive resistance training is effective for increasing muscle strength, muscle size, and functional capacity in older adults. Research shows that high-intensity resistance training programs that increase in volume and progression over time can keep sarcopenia and dynapenia at bay for advanced and beginner exercisers alike.
Resistance training has also been shown to improve gait speed – a measure of how quickly one can walk within a quantified distance. This is important because walking is a key physical performance indicator for people of all ages – but especially for older adults. Individuals with slow gait speeds tend to be at a higher risk for injury, cognitive impairment and falls.
A study published in the Journal of Physiotherapy concluded that 12 weeks of high-intensity resistance and functional exercise can significantly improve temporal and spatial characteristics of gait for older adults in the beginning stages of dementia. Another study showed that 12 weeks of resistance training improved walking speed and balance among adults aged 65 and older.
Resistance training improves gait because it improves muscle strength, and, of course, sufficient muscle strength is a requirement for our ability to walk. Resistance training is also a vital component in balance and fall prevention, however…
Strong muscles alone do not prevent falls.
There are other factors at play.
While research over the past two decades has repeatedly shown that resistance training and fall prevention programs promoting balance through building core strength and muscle memory decrease the rate of falls in senior populations, there is a third contributor to fall risk that has been largely ignored: A breakdown in executive functioning.
Just as the process of aging includes a natural loss of muscle mass and strength, research shows a gradual decline in the processes of the brain and central nervous system. As we age, the brain and spinal cord lose nerve cells and begin to atrophy. Nerve cells begin to pass messages throughout the body more slowly and waste products can collect in the brain tissue as nerve cells break down.
This breakdown of nerves can also affect our senses. Often this is most noticeable as a decline in our vision, hearing, and reaction time. Our senses receive information from our environment in the form of sound, light, smell, taste, touch, etc. This sensory information is converted into nerve signals that are carried to the brain. Inside the brain, these signals are turned into meaningful sensations. From the day we were born, a certain amount of stimulation is required before we become aware of it. No matter how sharp our hearing or vision, is there are sounds too soft to register and matter too small to see. As we age, the threshold of sensory stimulation rises. In other words, older adults require higher levels of stimulation to be aware of any given sensation.
Moving through normal, day-to-day life requires us to move our bodies in different directions. Bio-mechanically this means our bodies are constantly shifting the base of support necessary to accommodate changes in the center of mass. Just as older adults require a higher threshold of sensory input to register sensation, the internal mechanisms that allow us to shift our weight without falling over seem to decline. In other words – it takes longer for sensory information to pass through our senses into the brain where the brain registers its meaning and sends reactive signals to the rest of the body. That longer time spent processing stimuli from the environment in working memory has been shown to explain the deficit in motor processes common in many older adults.
Muscle strength is undeniably vital to active aging. We need strong muscles to move, perform daily tasks, and maintain our independence. However, focusing solely on muscle mass misses a critical piece of the puzzle: the nervous system. Our muscles are receivers of information, and if the communication lines between our central nervous system and our muscles are down, even the strongest muscles won’t function effectively. This disconnect is a major contributor to falls and injuries in older adults, highlighting the need to address nervous system health alongside muscle strength for truly active aging.
So, what do we do? We need to shift our thinking beyond just building muscle and recognize the crucial role of the nervous system in movement and balance. Strong muscles are a requirement for active aging, but they’re only one part of the equation. The central nervous system, which commands our muscles to move, is equally important. Age-related muscle loss (sarcopenia) is often linked to a decline in communication between the brain and muscles. This means that many skeletal muscle changes we see as we age aren’t just about the muscles themselves, but also about a lack of effective signalling from the nervous system.
Sarcopenia can be an early indicator of declining physical abilities, but it’s not always the direct cause of mobility problems. Structural changes in the body eventually lead to functional changes. For example, purposeful movement requires high-level cognitive function. Our prefrontal cortex processes information, assigns meaning, and then sends signals to our muscles, enabling us to respond to our environment. In older adults, this system slows down, increasing the risk of falls and injuries. Walking, a complex system of tasks we often take for granted when young, requires attention, executive functions, muscle strength, and memory. Breakdowns in any of these areas create cyclical problems that are the opposite of healthy, active aging.
Think of it this way: a powerful car is useless without a skilled driver. Similarly, strong muscles are ineffective without a nervous system that can properly direct them. So, what can we do to support both muscle strength and nervous system health as we age? Here are some key strategies:
1. Embrace Neuro-Muscular Exercise:
Traditional strength training focuses primarily on muscle hypertrophy (growth). While important, we also need exercises that challenge the connection between the brain and muscles. These “neuro-muscular” exercises, often called functional training, focus on balance, coordination, and agility. Examples include:
- Balance training: Exercises that challenge your balance, such as standing on one leg, using a balance board, or practicing Tai Chi.
- Coordination drills: Activities that require precise movements and coordination, like catching a ball while balancing or performing complex movement patterns.
- Agility exercises: Exercises that involve quick changes in direction and speed, such as cone drills or ladder drills (modified for safety).
2. Prioritize Cognitive Engagement During Exercise:
Make your workouts mentally stimulating as well as physically challenging. This can involve:
- Learning new movement patterns: Trying new exercises or dance routines that require you to think about the movements.
- Multi-tasking during exercise: Combining balance exercises with cognitive tasks, such as reciting the alphabet while standing on one leg.
- Using interactive fitness technology: Many new fitness platforms incorporate cognitive challenges into their workouts.
3. Maintain Cognitive Health Separately:
Just as we exercise our bodies, we need to exercise our minds. Engage in activities that challenge your cognitive function, such as:
- Puzzles and brain games: Crosswords, Sudoku, and other brain-training activities.
- Learning new skills: Taking a class, learning a new language, or playing a musical instrument.
- Staying socially active: Social interaction is vital for cognitive health. Connect with friends and family, join clubs, or volunteer in your community.
4. Focus on Functional Fitness:
Functional fitness focuses on exercises that mimic everyday activities, such as lifting, bending, and reaching. This type of training is particularly important for older adults as it directly translates to improved independence and reduced risk of falls. Functional exercises can include:
- Leg press, squats and lunges: These exercises strengthen the muscles used for sitting and standing.
- Stair climbing: A great way to improve lower body strength and cardiovascular fitness.
- Carrying groceries or other objects: Simulates real-life lifting tasks.
5. Seek Professional Guidance:
A qualified fitness professional can assess your individual needs and design a personalized exercise program that addresses both muscle strength and neuro-muscular fitness. They can also provide guidance on proper form and technique to minimize the risk of injury.
In Conclusion:
Active aging requires a holistic approach that considers both the physical and cognitive aspects of health. While muscle strength is essential, it’s only one piece of the puzzle. By incorporating neuro-muscular exercise, cognitive engagement, and functional training into our fitness routines, we can support both our muscles and our nervous systems, leading to greater independence, reduced risk of falls, and a higher quality of life as we age. It’s not just about being strong; it’s about being strong, coordinated, and connected – mind and body.