Osteoporosis, Age, Parkinson’s decrease dynamic balance and increase fall risk

Motor abilities influence an individual’s success in the performance of certain motor skills (Magill & Anderson, 2013). A motor ability of interest is dynamic balance, or the ability to maintain stability while one is in motion, as there is a strong correlation between poor balance and falls (although it is not the only factor), which are a large health concern among many populations (Ünlüsoy et. al 2011). I have had many clients with various conditions, including age, Parkinson’s disease, and osteoporosis, who were unsteady during locomotion due to poor dynamic balance.

All three of these conditions, age, Parkinson’s disease, and osteoporosis, have a negative influence on the dynamic balance category of motor abilities (Paolucci et. al 2014; Ünlüsoy et. al 2011). Age-dependent change in the musculoskeletal, sensory, and neural systems decrease balance ability in older adults (Maki & Mcllroy, 1996). Parkinson’s disease occurs in the brain’s basal ganglia when there is a lack of dopamine production in the substantia nigra, and it causes bradykinesia, akinesia, tremor, and muscular rigidity (Magill & Anderson, 2013).  Paolucci et al. (2014) state that a “balance disorder is one of the most important impairments” in this population due to statistics showing substantially greater incidence of falls among those with PD (70% of individuals with PD fall once a year and 50% of them fall twice a year in comparison to only 30% of healthy adults over the age of 65 who fall once in a year). Osteoporosis is a bone disease where bones become increasingly fragile from microstructure impairments in the bone tissue and decreases in bone mass. Ünlüsoy et. al (2011) demonstrated that dynamic balance in osteoporotic women was significantly worse than in healthy individuals.

There are many factors influencing one’s ability for dynamic balance during locomotion including muscle strength, interpretation of vestibular and proprioceptive information, and visual feedback (Paolucci et. al 2014). In terms of defining dynamic balance or any type of balance as a motor ability, Magill and Anderson (2013) state balance is a “multidimensional ability that is specific to the task or skill in which balance is involved,” and the specificity of motor abilities hypothesis postulates that individual motor abilities are relatively independent of one another. Given these assumptions, it is challenging to articulate the specific balance ability or abilities influencing locomotion.

If a client or patient came to me requesting help with dynamic balance while walking, I would perform various tests to rule out (or in) factors that may contribute to difficulty walking. I would assess muscular strength and endurance, especially in the lower extremity, observe the patient’s normal walking gait for noticeable abnormalities, and inquire into the patient’s medical history to rule out diseases or conditions, including those previously discussed, that may impact dynamic balance. I would also question the patient about lifestyle factors (i.e., recent accident or trauma, change in medication, etc.) that may be contributing to the deficit. If the patient has good muscle strength in the lower extremity, adequate gait mechanics, and no red flags in his or her medical history, this would indicate a problem with the motor ability of dynamic balance.

Additional ideas of assessments for dynamic balance related to gait were reviewed in a study by Bloem et. al (2016). This study recommended clinical tests including the UPDRS-derived Postural Instability and Gait Difficulty score, Berg Balance Scale, Mini-BESTest, Dynamic Gait Index, Freezing of Gait Questionnaire, Activities-specific Balance Confidence Scale, Falls Efficacy Scale, Survey of Activities, Fear of Falling in the Elderly-Modified, 6-minute and 10-m walk tests, Timed Up-and-Go, and Functional Reach (Bloem et. al, 2016). Further research on my part is needed into these methods, but any would be reliable assessments of dynamic balance.

Motor abilities limit a person’s success in performing a motor skill. In the case discussed, dynamic balance is a motor ability that, if affected, can decrease one’s success at walking without falling. I believe it is important to note that while motor abilities may limit achievement in another skill, motor abilities themselves can be practiced, coached, and improved which would also benefit the motor skill performance. The most important part of treating a motor ability deficit is identifying and distinguishing it from other possible causes of poor motor skill performance.

References

Bloem, B. R., Marinus, J., Almeida, Q., Dibble, L., Nieuwboer, A., Post., B.,…Schrag, A. (2016). Measurement instruments to assess posture, gait, and balance in Parkinson’s disease: Critique and recommendations (abstract only). Movement Disorders. doi:10.1002/mds.26572

Magill, R. A. & Anderson, D. I. (2013). Motor learning and control: Concepts and applications (10th ed.). New York, NY: McGraw Hill.

Maki, B. E. & Mcllroy, W. E. (1996). Postural control in the older adult (abstract only). Clinical Geriatric Medicine, 12(4), 635-58.

Nakano, W., Fukaya, T., Kobayashi, S., & Ohashi, Y. (2016).  Age effects on the control of dynamic balance during step adjustments under temporal constraints. Human Movement Science, 47, 29-37. doi:10.1016/j.humov.2016.01.015

Paolucci, T., Morone, G., Fusco, A., Giuliani, M., Rosati, E., Zangrando, F., & … Iosa, M. (2014). Effects of perceptive rehabilitation on balance control in patients with Parkinson’s disease. Neurorehabilitation, 34(1), 113-120. doi:10.3233/NRE-131024

Ünlüsoy, D., Aydoğ, E., Tuncay, R., Eryksel, R., Ünlüsoy, İ., & Çakcı, A. (2011). Postural Balance in Women with Osteoporosis and Effective Factors. Turkish Journal Of Osteoporosis / Turk Osteoporoz Dergisi, 17(2), 37-43.

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Resistance Train for Bone Health

Let’s look at bones:

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You know how all the commercials say that the calcium in milk helps build strong bones? Well, resistance training is another essential component.

What exactly is resistance training?

Defined by ominous Google, resistance training is any exercise in which muscles contract against external load. This load can be body weight, band resistance (with mini loops or resistance bands), or fixed weight (utilizing barbells, dumbbells, kettlebells, machines, and weight plates).

There are two important things to know about the body:

  1. Bone is constantly being remodeled (formed) and resorbed (degraded). In adults, about 10% of bone is remodeled every year.
  2. The body likes to be as efficient as possible with muscle and bone. In order to avoid spending extra energy lifting heavier than necessary bone or muscle day to day, the body will decrease bone density or muscle mass if they are not regularly used.

How does resistance training stimulate bone growth?

The bones in our bodies have a threshold called minimal essential strain (MES). This is the amount of weight [load] a bone must experience for new bone growth to be stimulated and it is regulated by bone cells so that forces experienced on a regular basis don’t exceed it. The process of bone adaptation begins within the first few weeks after a stimulus above MES, but it is also a long term process; it requires six or more months and regular forces greater than MES to result in increased bone density. Activities that generate forces greater than MES include those that are weight bearing and high intensity (i.e. resistance training).

Why is stimulating bone growth important?

  1. Adequate bone strength and thickness are important for preventing injuries such as fractures and stress fractures.
  2. It is important to stimulate bone growth because through the majority of our adult lives our bone density is actually decreasing, especially in women. Mh6o0ppOur bone density peaks when we are between 25 and 40 years old and decreases from that point on. It is important that we get our peak as high as possible through our 20’s and 30’s, and it is essential for those over 40 to preserve as much bone density as they can. Regular resistance training by older adults has been shown to offset age-related declines in bone health.
  3. In those with osteoporosis or osteopenia (diseases where bone mineral density is reduced to critically low levels), resistance training can beneficially stimulate bone growth .

Or else…

Here’s two images depicting the prevalence of fractures from weak, osteoporotic bones that occur with age and gender.

osteoporosis_1

osteoporosis_2

How should one exercise to achieve increases in bone density?

There are a couple components to consider in order to best stimulate bone growth with your workouts:

  1. Specificity of Loading: Exercises must directly load a particular region of the skeleton to induce bone growth. For example, bodyweight squatting loads the pelvis and leg bones but not the arm bones or ribcage. Pushups load the arm bones but not the leg bones.
  2. Speed, Direction, and Variability of Loading: Loading of bone is only osteogenic (bone-growth inducing) if the weight is moved (it can’t just be held in place (static). Also, variety in exercises (changing exercises every 3-4 weeks) ensures that all bones receive stimulus.
  3. Proper Exercise Selection: Best exercises for inducing bone growth involve heavy loads, multiple joints, and forces directed through the spine and hips. Examples of these type of exercises are squat, lunge, deadlift, row, and press variations.
  4. Progressive Overload: Once a bone adapts to a given strain level, the MES (stimulus for bone to form) is higher. Overtime, the weights lifted or intensity of exercise must gradually increase in order to continue stimulating bone growth.

 

Baechile, T.R., Earle, R.W.. Essentials of Strength Training and Conditioning. Third Edition. NSCA, 2008.

Bilezikian, J.P., Raisz, L.G., Rodan, G.A.. Principles of Bone Biology, Second Edition. Volume 1. Academic Press, 2002.

McNeely, E.. Training to Improve Bone Density in Adults: A Review and Recommendations. U.S Sports Academy. July 9, 2010. 

Moreira, Linda Denise Fernandes, Oliveira, Mônica Longo de, Lirani-Galvão, Ana Paula, Marin-Mio, Rosângela Villa, Santos, Rodrigo Nolasco dos, & Lazaretti-Castro, Marise. (2014). Physical exercise and osteoporosis: effects of different types of exercises on bone and physical function of postmenopausal women. Arquivos Brasileiros de Endocrinologia & Metabologia58(5), 514-522. https://dx.doi.org/10.1590/0004-2730000003374