THE MEDICAL SCIENCE BEHIND THE NYMBL DUAL-TASKING APPROACH TO BALANCE IMPROVEMENT
Research on the Dual-Tasking approach to reflexive balance improvement, and Nymbl’s Unique method of implementing this for users
This page outlines the available research on dual-tasking interventions and balance improvement, and how this research is implemented in the Nymbl System. We have also conducted studies of balance improvement from using Nymbl, which are summarized on our Validation of the Nymbl Balance Platform article.
Research Confirming that Dual Tasking significantly improves balance
The Effect of Cognitive Dual Tasks on Balance During Walking in Physically Fit Elderly People.
van Iersel MB1, Ribbers H, Munneke M, Borm GF, Rikkert MG.
OBJECTIVE: To evaluate the effect on balance of 3 different cognitive dual tasks performed while walking without and with standardization for gait velocity, and measured with both foot placements and trunk movements.
DESIGN: Cross-sectional study.
PARTICIPANTS: Fifty-nine physically fit elderly people (mean age, 73.5y).
INTERVENTIONS: Not applicable.
MAIN OUTCOME MEASURES: Stride length and time variability measured with an electronic walkway, body sway measured with an angular velocity instrument, and gait velocity.
RESULTS: Overall, dual tasks resulted in decreased gait velocity (1.46 to 1.23m/s, P<.001), increased stride length (1.4% to 2.6%), and time variability (1.3% to 2.3%) (P<.001), and had no significant effect on body sway. After standardization for gait velocity, the dual tasks were associated with increased body sway (111% to 216% of values during walking without dual task, P<.001) and increased stride length and time variability (41% to 223% increase, P<.001).
CONCLUSIONS: In physically fit elderly people, cognitive dual tasks influence balance control during walking directly as well as indirectly through decreased gait velocity. Dual tasks increase stride variability with both mechanisms, but the increase in body sway is only visible after standardization for gait velocity. The decreased gait velocity can be a strategy with which to maintain balance during walking in more difficult circumstances.
Patima Silsupadol, Ka-Chun Siu, Anne Shumway-Cook, Marjorie H Woollacott
Physical Therapy, Volume 86, Issue 2, 1 February 2006
Michail Doumas Michael A. Rapp Ralf Th. Krampe
The Journals of Gerontology: Series B, Volume 64B, Issue 2, 1 March 2009
Dual tasking approach in the Nymbl System
Nymbl combines simultaneous exercise with cognitive training to improve reflexive balance. It is crucial to improve reflexive balance, because people fall when they are distracted and the reflex of balance needs to be enhanced. Nymbl does this by:
– strengthening core muscle groups required to stand erect and maintain a good walking posture
– improving flexion of muscles needed for correct spine alignment
– stimulating the cerebrum & cerebellum through the double attention required to hold the body in certain positions whilst solving cognitive puzzles
Isometric Exercise and Core Muscle Strength
The Journal of Applied Research shows that isometric exercise improves muscle strength faster than dynamic exercise.(2) Energy is only spent on increasing tension in the muscles without it being wasting on motion causing fatigue, therefore, making it possible to reach maximum levels of strength in minimum time. Isometrics increase flexibility and decrease injuries. They require body and brain to fire up all muscle fibres in a maximal voluntary contraction to succeed.(3) Furthermore, between lunges, wall sits and unipedal stands a high number of key muscle groups are engaged.
Posture & Spine Alignment
Dr Farcy explains “The body’s balance for a major part is maintained by the cervical action of all neck muscles, insuring the inner ear’s vestibular stability when acceleration is transmitted to the head by body motion. Head control does not only guarantee good function of the oculo-vestibular reflex, it ensures enlarged perception of the environment, and by extension of its specific input at each given moment.” (4)
Nymbl exercises keep the head up and the gaze horizontal through the action of holding arms stretched out and focusing on a screen at eye-level.
Isometric Exercise and proprioception
Proprioception is our sense of the relative position of one’s own parts of the body and strength of effort being employed in movement. The proprioceptors are sensors that give the brain information about the position of the limb in space at any given time. “Many neural pathways synapse at various levels of the central nervous system, integrating all this information to provide us with both a conscious and non-conscious sense of where we are and how we are moving.” (7)
Clearly this aptitude is vital for good balance. These two aspects of proprioception – conscious and unconscious – are both vital for safe activity but they become impaired as we age. Falls frequently result when the brain of a senior is ‘overloaded’; for example, they are in the middle of walking and something unexpected happens. Isometric exercise requires conscious effort and concentration to hold positions without flagging or falling and this stimulates the cerebrum – the part of our brain that controls all voluntary actions in the body – then the Nymbl system adds in removal of visual context (asking you to close your eyes) or an additional cognitive load, such as asking you to answer quiz questions. This deliberate ‘overload’ forces the brain to move the conscious concentration on the holding the exercise pose into unconscious activity whilst it consciously focuses on solving puzzles. This stimulates the cerebellum which is responsible for coordinating the unconscious aspects of proprioception, ergo, often attributed as responsible for balance.
The effects of proprioceptive training on improving motor function are widely researched. (8)
Brain Plasticity, Isometric training & cognitive exercise
“The non-conscious sense of embodiment is essential for timely, appropriate neuromuscular coordination” (9) and whilst it was second nature when we were young, in age it declines, impairing our balance and making us vulnerable to falls. At the heart of this decline is the closing down of synapses in our brain, or in other words, reduced brain plasticity.
Isometric exercise already requires the integration of a huge amount of information from our muscles, vision, perception, vestibular system, in milliseconds by the brain. Adding an extra cognitive load in the form of puzzles, quizzes, and games enhances the stimulation of the synapses which improve brain plasticity.
(1) Human Physiology: From Cells to Systems, Lauralee Sherwood
(2) Journal of Applied Research 2006 “In fact, using isometric exercise for 6 minutes would be the equivalent muscle work of 30 to 35 minutes of gym work on commercial weight lifting equipment.” https://bdxbiomechanics.com/isometric-research-studies/
(3) See Thépaut-Mathieu C(1), Van Hoecke J, Maton B for studies on increased strength, power and muscle mass through isometric training
(4) (a) text book name “The wide sweep of a gaze of the eye with the multiple degrees of freedom of movement of the head, is one of the best guarantees of a continuous enrichment of cognition”
(5) The hip extension criteria are well documented by Istvan Hovorka’s research text book name ( chapter 7 )
(6) Stretching your hip flexor is a good start towards pelvic alignment. https://healdove.com/disease-illness/The-Importance-of-Reversal-of-Cervical-Lordosis
(7) International Association for Dance Medicine & Science
(8) The effectiveness of proprioceptive training for improving motor function: a systematic review – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4309156/
(9) International Association for Dance Medicine & Science