Earlier this month, we hosted a webinar with Dr. Eling D. de Bruin, PT PhD from the Karolinska Institute, Stockholm, Sweden, about the role of exergames in fall prevention.
During the webinar, Dr. Eling discussed the leading causes of falls including one of the most surprising contributors – the brain. Often, when we think about the age-related causes of falls, we think about decreases in strength and balance. But, research over the past few years shows that the changes in the brain is just as much, if not more, of a contributor to falls.
Dr. Eling also covered important mobility components of aging populations including:
- muscle strength
- gait speed
- gait variability
- executive functioning
Each of these components contribute to our ability to move around in complicated environments without falling. Most importantly, Dr. Eling discusses current research that outlines the extremely important role that exergames can plan in Fall Reduction Programs.
The World Health Organization (WHO) defines healthy aging as, “the process of developing and maintaining the functional ability that enables well-being in older age.” When we talk about healthy aging, we are primarily talking about two functions that enable us to age in a healthy way:
- Intrinsic Capacity: “the combination of the individual’s physical, mental, and psycho-social, capacities.” These factors affect mobility, cognition, vitality (psycho-social and neruo-social), vision, and hearing.
- Functional Capacity: “having the capabilities that enable all people to be and do what they have reason to value.”
Intrinsic Capacity vs. Physical Fitness
Not surprisingly, intrinsic capacity is related to cognition, our ability to move around safely in challenging environments, psychological well-being, sensory systems, and general vitality. Realizing this, it’s not difficult to see how intrinsic capacity relates directly to physical fitness. For the sake of discussion, it might be helpful to define exactly what we mean by physical fitness.
It’s important to note that physical fitness is not only health-related, affecting our cardio-respiratory, muscle strength, and body composition, but also skill-related, which means it’s affected by agility, balance, coordination, speed, power, and reaction time.
In order for healthy aging to occur, we as exercise and healthcare professionals know that we must focus on both health and skill-related aspects of overall fitness.
Vicious Cycle of Frailty
The most important factor that explains why some people fall into the cycle of frailty, is sarcopenia. Sarcopenia is, of course, age-related muscle loss. Sarcopenia leads to a decrease in strength and power. When we get weaker, we tend to decrease our level of physical activity, are prone to malnutrition, and so on.
We know that regular, consistent training is key to helping people not fall into this cycle of frailty. But, what type, of exercise, or combination of exercises, can improve strength and age-related health declines such as gait speed?
One meta-analysis concluded that progressive, high-intensity resistance training is the most effective exercise modality for improving preferred gait speed. Sufficient muscle strength seems an important condition for improving preferred gait speed. In other words…
Progressive resistance training is the most effective thing we can do to fight the Cycle of Frailty.
However, if we look at the optimal way to prevent falls, other important factors emerge. Another meta-analysis revealed that strength training AND balance training are important for healthy aging, but “the inclusion of strength training does not seem to be crucial for an effect of exercise on falls.”
This seems to be a contradiction. On the one hand, research clearly points to the benefit of progressive resistance training on healthy aging. On the other hand, strength alone will not decrease your chance of falling. Why?
To answer this question, one group of researchers closely examined several videos capturing people falling. One video shows an elderly woman walking down a hallway and accidentally bumping into an object – the only object in the hallway – which causes her to fall. Another video shows an elderly man successfully throwing and catching a ball and then suddenly, without any apparent cause, losing his balance and falling over. A third example is of a man walking down a hallway, holding a dog on a leash, and suddenly falling down. In the video, neither the dog or the leash seem to be a contributor to the fall.
The videos seem to indicate that falls happen not because of weak muscles, but because of an impairment in sensory filtering, which is getting effective information out of the environment and where the body is in the environment and our ability to react. This process happens in the brain. Cognitive working memory changes in aging lead to slowing down of motor response selection.
The Relationship Between Cognitive Functions and Falls
In one study that examined executive control deficits as a prodrome to falls, healthy older adults were measured for only one thing: cognitive ability, as measured by executive functions. Executive Functions are those tasks that we need to be able to process important information from the environment and use it in a meaningful response such as walking and preventing a fall.
The study found that among healthy older adults, individuals with poor executive functioning were more prone to falls. The research indicates that higher-level cognitive functions such as those regulated by the frontal lobes are apparently needed for safe everyday navigation that demands multi-tasking.
Fall Prevention is Not Only About Muscle Mass
Research shows that there is no equivalence between muscle mass and strength. This means that there are adaptions in other properties in the human neuromuscular system that are involved in the regulation of strength. In fact, we know that mechanisms accounting for an increase or decrease in strength can arise from neurological and skeletal muscle factors.
As we age, we can experience increases in muscle mass and decreases in muscle strength. This is true for both men and women. Likewise, we can experience increases in muscle strength without any increases in muscle mass.
So, if it’s not muscle mass, what is it?
If we look for examples in the peripheral nervous system, we see that these structures show age-related changes. As we age, we experience atrophy and degeneration in our frontal cortex, slowed regeneration of pyramidal neurons, and a loss of dopamine neurons. All these changes in the brain have functional consequences such as variable motor performance, reduced neuroplasticity, and impaired sensorimotor integration. In addition, there is a decrease in communication within the brain and in the speed of information between the brain and the body.
We see similar decreases in the peripheral nervous system. As we age, there is a degeneration of motoneurons, slowed axonal regeneration, and changes in the neuromuscular junction. These changes also have functional consequences including slowed nerve conduction, neuromuscular junction transmission failure, chronic inflammation, and oxidative stress. These changes naturally affect our skeletal muscular systems and their ability to quickly receive important information from the brain. These changes have a direct impact on our body’s ability to produce strength.
A 2011 study found that deficits in the neural drive can contribute to much of the muscle weakness observed in the very elderly – at least in the knee extensor muscles. There is also evidence for a deficit in activation of the knee extensors, which are clinically important as the level of muscle strength has been linked to disability development and functional capacity.
What does all this have to do with walking and falls?
Motor control integrates both cortical and subcortical structures principally involving those connections between the basal ganglia and frontal lobes involved in automaticity of motor function and its cognitive mediation.
In other words, our brain activity tells our muscles what to do. And, if we want to react quickly to obstacles in our environment, we are dependent on our executive functioning working at top form. Gait in the elderly is a complex motor-cognitive task involving muscles and healthy brains.
To prevent falls, we must train both the brain and the muscles.
So, how can we keep the brain healthy?
Neurological health depends as much on signals sent by the body’s large, leg muscles to the brain as it does on directives from the brain to the muscles. When physical activity is limited, the number of neural stem cells can decrease by as much as 70%. Both neurons and oligodendrocytes — specialized cells that support and insulate nerve cells — don’t fully mature when exercise was severely reduced.
Using the legs, particularly in weight-bearing exercise, sends signals to the brain that are vital for the production of healthy neural cells, essential for the brain and nervous system. Cutting back on exercise makes it difficult for the body to produce new nerve cells
New Technologies and Neuroplasticity: Virtual Reality and Exergames
Practicing movements results in performance improvements and greater plasticity of the motor cortex. Non-practicing has the opposite effect! This is what we call positive and negative neuroplasticity.
Positive neuroplasticity increases our cognitive reserve and promotes new neural connections. Better brain health results in better cognition, and better cognition results in better everyday functioning that allows us to live healthy, active, independent lives.
Examples for promoting positive neuroplasticity include:
- Mental stimulation
- Intellectual pursuits
- Social interaction
- Good emotional health
- Physical exercise
- Proper nutrition
- Proper sleep
- Cognitive remediation therapy
Examples for promoting negative neuroplasticity include:
- Non-stimulating activities
- Social isolation
- Poor emotional health
- Sedentary lifestyle
- Inadequate nutrition
- Inadequate sleep
- Substance abuse
How Physical Exercise Supports Positive Neuroplasticity
There are two primary ways to support brain and body health. The first is sequential motor-cognitive training which involves cognitive exercises that follow physical exercise training sessions. The second is simultaneous motor-cognitive training which involves cognitive exercises that are performed at the same time as physical exercise. Both are effective in supporting positive neuroplasticity. However, simultaneous motor-cognitive training is more effective.
The Theory of Using Exergames as Medicine
Exergames are technology-driven physical activities such as video gameplay that require participants to be physically active or exercise in order to play the game. Exergames tap into both physical and cognitive functions at the same time. By interacting with a virtual environment, we are able to activate our brains AND our muscles.
Exergames integrate cognitive tasks that increase neural plasticity while activating the large muscles in the legs. This results in increases in neural activation.
Differing outcomes between types of exergames
Is it important what kind of game we use? Yes. The most effective exergames tap into the totality of postural control. This is important because currently, most exergames do not train for postural control. Many kinds of commercial exergames today do not provide enough sensory integration and reactive postural control.
Exergames that utilize a changing base of support better meet the requirements for training postural control. This means using an exergame that requires you to lift your feet from the base of support repeatedly. Games that require only bodyweight shifts in movement, rather than moving your feet, are not as effective.
The Dividat Senso: The Missing Link
The Dividat Senso forces the user to constantly change their base of support by responding to a virtual scenario played on a screen in front of them. The user must interact with the information on the screen, process the information in the brain, and then put that information into meaningful action.
The Dividat Senso is a scientifically based dual-tasking interactive cognitive motor training system that requires multiple sensory inputs: Auditory, Visual, and Sensory. It includes a user-friendly interface and games that simulate everyday movements and automatic progression that’s been proven to improve both physical and cognitive function.
The Dividat Senso creates a virtual environment with cognitive challenges. The system automatically adapts to each user’s individual ability level, progressing in difficulty as they improve. It offers customized routines designed to improve specific cognitive and/ or balance weaknesses along with goal setting and individual progress reports to measure outcomes.
The Dividat Senso’s 25+ games train for:
- Sustained attention
- Working memory
- Divided attention
- Reaction time
- Cognitive flexibility
- Visuo-Spatial Skills
Dividat Senso training is personalized to address each person’s unique needs and adapts to provide progressive challenges to each individual user.Back