Tag Archives: longevity

Explaining Life Expectancy

Individual controls aging, Life expectancy, , , ,

Introduction

The most significant achievement of the twentieth century was the near doubling of human life expectancy from 47 to 76 years of age.  Although life expectancy is a demographic value, meaning it is an indicator of population aging, nevertheless, it reveals important aspects relevant to individual aging.  This blog will explain life expectancy with a specific focus on:  its determination and underlying assumption, the reasons for the dramatic increase since the 1900s and its relevance to healthy longevity.

What exactly is life expectancy?

“Life expectancy at birth represents the average number of years that a group of infants would live if the group was to experience throughout life the age-specific death rate present at the year of birth” (Murphy et al., 2013).  The unmet assumption lies right in the definition which states that the age-specific death rate at birth remains unchanged throughout life.  But since age-specific death rates change constantly throughout life, life expectancy, at best, represents an estimate of one’s possible lifespan.  Despite the unmet assumption, life expectancy also denotes the health of a population.  Accordingly, the US ranks 29th out of 38 similar developed countries in life expectancy (Organization for Economic Co-Operation and  Development, 2019).  Sadly, the US spends almost twice as much on healthcare compared to the average spending of the top ten countries with higher life expectancies (e.g. Norway, Australia, UK, Switzerland). (https://www.commonwealthfund.org/publications)

Given its less than rigorous premise, life expectancy, however, consistently reveals an unexplained gender gap in which life expectancy of females exceeds that of males by approximately 4-5 years (topic of a future blog).  As of 2021 (Arias et al., 2022), life expectancy was 79.1 years for females, 73.2 years for males and 76.1 years average of both genders.  Secondly, in recent years, life expectancies of subpopulations based on Hispanic origin and race show significant differences.  Specifically, life expectancy (average of both genders) is highest for Asians (83.5 years), followed by Hispanics (77.7 years), Whites (76.4 years), Blacks (70.8 years) and American Indians/Alaska Native (65.2 years).  

Doubling of life expectancy and recent changes

First Half of Twentieth Century

The greatest improvement in life expectancy occurred in the first half of the twentieth century.  This resulted from societal advancements in the handling of sewage, sanitation, and clean water which came about after acceptance of the Germ Theory of Infections proposed by Louis Pasteur, Robert Koch and others.  The Germ Theory of Infections also opened the way for the development of vaccines for diphtheria, whooping cough and tetanus and the launch of sulfa drugs and antibiotics e.g. penicillin.  Together, these changes decreased the mortality rate of infants and children, allowing them to survive to older ages, pushing life expectancy up.

Second Half of the Twentieth Century

The second half of the twentieth century also contributed to increasing life expectancy but in different ways and to a lesser extent.  There was a decrease in infant mortality with acceptance of hospital births favored over home births.  However, more significantly, there was a decline in mortality rates among older individuals due to several developments.  First, protocols for long term management of chronic diseases were established, especially for cardiovascular disease, the major killer of the elderly.  Specifically, identification of more effective drugs, implantable medical devices (pacemakers, stents, defibrillators) and safer surgical procedures added years and increased life expectancy in the US population.  Secondly, access to Medicare and Medicaid provided affordable health care for many. Thirdly, a scientific focus on aging ushered in effective lifestyle choices to maintain the healthspan and decrease mortality.

2014 to 2017

Life expectancy peaked in 2014 at 78.9 years (average of both genders).  A slight decrease in life expectancy occurred from 2015-2017 and might not be significant except for the fact that even this small decline was, unprecedented and due, unfortunately, in large part to an increased mortality rate in young individuals from drug overdoses (opioids), suicides, homicides, and an uptick in deaths in older adults due to Alzheimer’s and cardiovascular disease (Harper et al., 2021). 

2020-2021

Life expectancy experienced a sizeable (0.9-1.8 year) decline in 2020 (77 years) and 2021 (76.1 years), considered the biggest two-year decline in life expectancy since 1921-1923 (CDC National Center for Health Statistics).  This decrease in life expectancy is no surprise.  It resulted from the spike in deaths due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), better known as the COVID-19 pandemic.  Sadly, many of the negative factors identified in 2015-2017 such as drug overdoses remained an additional contributing factor to the decline in life expectancy in 2020 and 2021. 

Significance of life expectancy to aging

From the discussion above, it is evident that many incredible societal and medical advances have removed environmental hazards, thereby, permitting individuals to reach older ages and in some cases approach the true life span (~119 years of age) of man.  Despite this, the rate of aging in humans has not changed.  In fact, if the life expectancy graphs are transformed to yield a value called the mortality rate doubling time for humans, it is apparent that from the 1900s onward, the mortality rate doubling time remains constant at 8 years beginning at puberty (lowest mortality rate).  Since the mortality rate at puberty is extremely low, doubling that every 8 years gets one to about 119 years of age, which is the oldest validated age reached by humans.

Life expectancy and lifespan

Life expectancy relates to the characteristic human rate of aging. The rate of aging relates to survival, hence lifespan and longevity.  While the human-specific mortality rate signifies inevitable physiological deterioration, it does not mean that aging is biologically programmed.  Far from it, no master “age-directing” programs (genetic or otherwise) are known to exist.  Aging is highly variable from one person to another exactly because it results primarily from environment  factors (e.g. lifestyle choices) and the complex interaction of the environment with our genes (see Insight 1).   

Gerontological investigations show that age changes accrue due to the slow loss of stress resistance, also referred to as loss of essential maintenance and repair mechanisms. Lifestyle choices that optimize those systems of maintenance and repair minimize aging.  Previous blogs discuss many of these lifestyle choices, in particular the 4-prong exercise program (aerobics, resistance, balance, stretch)(see Insight 2; Insight 3: Ways to retard skeletal muscle aging ; Insight 4: Anti-aging benefits of aerobic and stretch exercises; Insight 5 – Optimizing Balance) enhance these maintenance and repair mechanisms to optimize stress resistance.

Expansion or Compression of Healthspan

Does the increase in life expectancy (longevity) evident over the last 100 years come with extra years of health (absence of disease and disability) or with an extension of disease and disability (extended senescent span)?  At present there is no consensus on an answer. This is because there is no agreement on a) exactly what is an age-related disease, b) whether disease is more important than disability and c) how to quantify the social/psychological impact of disease/disability on quality of life.  However, if one considers the ongoing effort of the scientific community to precisely define biological pathways involved in aging and to validate, through clinical trials, effective ways to minimize aging, it seems that each individual should be able to achieve extra years with health rather than with disease and disability.

Change in Life Expectance from 1900 to the Present
References

Arias E, Tejada-Vera, Kochanek KD, hmad FB.  Provisional Life Expectancy Estimates for 2021. Vital Statistics Surveillance Report, August 2022. https://www.cdc.gov 

Harper S, Riddell CA, King NB.  Declining Life Expectancy in the United States: Missing the Trees for the Forest. Annu. Rev. Public Health  42:381–403, 2021

Murphy SL, Xu J, Kochanek KD. Deaths: final data for 2010.  Natl Vital Stat. Rep 61: 1-118, 2013.

Insight 11 -Okinawa, DASH and Portfolio Diets

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Diet to extend the health span

Innumerable scientific studies show that adherence to the Mediterranean Diet reduces deaths due to cardiovascular disease and therefore, increases the lifespan (see Insight 10).  As discussed below, several other diets, Okinawa, DASH, and Portfolio, reduce risk factors for cardiovascular disease. 

1.  Okinawa Diet

Background

Okinawa is a Japanese island where life expectancy since the end of WWII has been the highest in the world.  Although Okinawan life expectancy today is no longer higher than the Japanese national average, nevertheless, life expectancy in Japan relative to other countries remains exceptionally high.  As proof, Japan’s life expectancy ranks second among 191 countries  (average of both genders, 85 years in 2020  (www.worldometers.info/demographics/life-expectancy/). By comparison, life expectancy in the USA ranks 46 among 191 countries.

Okinawa Dietary Components

The Okinawa diet is the main factor contributing to the longevity of Okinawans and the plethora of centenarians.  The Okinawa diet is a plant-based diet that is high in consumption of vegetables and thus low in calories. Although low in calories, the diet is nutritionally dense with an abundance of vitamins and compounds with antioxidative effects.  Interestingly, the preferred vegetable, the sweet potato, is one with a low glycemic index, meaning it is metabolized slowly thus avoiding high surges in blood sugar that predisposes one to pre-diabetes and subsequent Type 2 Diabetes.  The diet includes moderate consumption of proteins and a selection of mono/polyunsaturated fatty acids in place of saturated fats.  Diet details are summarized below.  

Okinawa Diet Benefits

Clearly, the traditional Okinawa Diet as practiced by residents of Okinawa effectively forestalls the onset of age-associated diseases and increases the lifespan.  As discussed earlier (Insight 8), lifelong caloric restriction in many animal models from round worm to monkey, not only dramatically extends the maximal lifespan but reduces inflammation,  improves insulin sensitivity, and delays onset of diseases.  The Okinawa Diet is low in calories so it may provide benefits simply through reduction in calories. 

Additionally, the Okinawa diet is low in protein and high in low glycemic carbohydrates.  When mice are maintained on a diet comparable to the Okinawa Diet, their life span increases significantly.   Human dietary studies are difficult to perform but generally low protein consumption is not associated with a decrease in mortality.  On the contrary, diets high in protein and low in carbohydrates (opposite to the Okinawa Diet) are associated with increased mortality.  More data are needed to understand the role of protein in aging. 

Freshly dug sweet potatoes

2.  DASH Diet

Background

The DASH diet was developed more than 20 years ago to reduced the prevalence of hypertension.  DASH is an acronym for Dietary Approach to Stop Hypertension.  The prevalence of hypertension increases with age.  The prevalence in adults is ~ 30%, in those 65-80 years ~58% and as high as ~74% in those over 80 years of age.  Furthermore, elevated blood pressure predisposes one to cardiovascular diseases such as atherosclerosis, stroke and heart failure.

DASH Dietary Components

Previous science indicates that certain foods could possibly lower blood pressure better than other foods.  This became the basis of the DASH diet. This diet recommends consumption of fruits and vegetables, whole grains, low-fat dairy products, beans, nuts and seeds and some fish and poultry.  Also consumption of saturated and trans fatty acids and cholesterol is reduced.  This diet is rich in nutrients such as potassium, magnesium, calcium, and fiber and lower in sodium compared to a Western Diet.

The Mayo Clinic has put together 3 days of meals that follow the DASH dietary plan.  Also included is the nutritional analysis of the foods for the 3 days.  It is worth checking out.  https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/dash-diet/art-20047110

DASH Benefits

Numerous clinical trials show that the DASH Diet lowers both systolic (high number) and diastolic (lower number) blood pressure with greater reduction of blood pressure in those with higher baseline values.  Reducing sodium in the DASH Diet below the recommended amount produced an even greater reduction in blood pressure.

3.  Portfolio Diet

Background

This diet was developed to lower cholesterol and to prevent/reduce the onset of coronary artery disease. It was designed with scientific information that suggested certain foods (such as plant proteins and sterols, viscous fibers, nuts)  in various ways were helpful in reducing cholesterol.  High blood levels of LDL (bad cholesterol) is a serious risk factor for cardiovascular disease.

Portfolio Diet Components

The Portfolio Diet is basically a vegetarian diet.  It is rich in vegetables such as broccoli, eggplant, tomatoes, onions, okra, high in whole grains including oats and barley, and vegetable-based margarine, almonds, and soy protein. Soy products replace animal products and the accompanying saturated fat.  It is also low in sodium,  sweets, and refined carbohydrates.

WebMD has published a plan for what the typical Portfolio Diet would look like in daily life.  This is worth reading.  https://www.webmd.com/cholesterol-management/features/portfolio-diet-lower-cholesterol

Portfolio Diet Benefits

A systematic and meta-analysis in 2018 of the Portfolio diet in clinical trials longer than 3 weeks showed many benefits.  Benefits were reduction in LDL cholesterol, decrease in systolic/diastolic blood pressure, reduction in inflammatory factors and decreased risk of coronary heart disease.

Conclusions:

Whether you follow the diets discussed here or the Mediterranean Diet discussed earlier (Insight 10), there is ample evidence that inherence to these diets will result in longer healthier life.  Of the four diets, the scientific support for the Mediterranean Diet is the most extensive, but quality data also exists for the other three.

It is clear that all 4 diets differ radically from the typical Western diet.  The Western Diet is high in calories, saturated fats, meat and meat products, processed foods and sugar-laden foods. Consumption of fruits, vegetables and fiber is low.  Furthermore, the Western Diet is associated with development of obesity and cardiovascular disease.

Insight-11-referencesDownload

Insight 9 – Replacement for caloric restriction

Diet, Individual controls aging, , , , ,

The caloric restriction mimetic – better than starvation

Caloric restriction (CR) is severe reduction in calorie intake.  It must be maintained for an extended period of time and be supplemented with essential nutrients.  It is often called “starvation without malnutrition”.  However, the reward of this difficult protocol is exceptional:  a longer and healthier lifespan (see Insight 8).  The obvious problem is that, unlike animals under investigative experimentation, humans cannot endure this degree of starvation for any significant length of time.  Thus the search for drugs that would produce the same benefits of CR without the pain of eating less.  These drugs are termed caloric restriction mimetics (CRMs).

The caloric restriction mimetic – 3 of interest:

1.  Sirtuin (SIRT)-activating compounds e.g. resveratrol

2.  Metformin

3.  Rapamycin

Sirtuin-activating compounds

Sirtuin-activating compounds stimulate specific genes (SIRTs) to produce proteins termed sirtuins.  Sirtuins (chemically defined as NAD histone deacylases), in turn, act to change cell metabolism for the better.  Sirtuins perform several significant functions.  Some of these are 1) reduction of inflammation through depression of the master gene (NF-κβ), 2) greater recycling of damaged proteins, and  3) improvement of insulin signaling.  Together these activities and many more contribute to a healthier life.

How are sirtuins related to CR?  In animal models of aging, CR activates the genes (SIRT family) that produce the sirtuins and consequently, the level  of sirtuins increases with CR.  Secondly, in genetic experiments which insert an extra SIRT gene into an experimental animal, the level of sirtuins increases and beneficial changes comparable to CR occur.  So chemicals that elevate the level of sirtuins should produce the same beneficial effects of CR.  Thus the development of sirtuin-activating compounds.

Resveratrol – role in caloric restriction

A notable sirtuin-activating compound is resveratrol, originally isolated  from red wine and when concentrated (1000 fold), resveratrol produces effects similar to CR such as an increase in maximal lifespan, reduced inflammation, and delay in disease onset.   Unfortunately, resveratrol is poorly absorbed by the gastrointestinal tract and so analogs with greater bioavailability have been developed.  Analogues have been evaluated in rodents and in man.  Generally in rodents, improved health benefits e.g. delay in disease onset have been observed. 

In man, clinical trials assessing one particular analogue, SRT2104, for therapy of psoriasis, ulcerative colitis, sepsis, and vascular dysfunction in smokers and type 2 diabetes (T2D) have been completed.  Thus far only results for the effect of oral SRT2104 on psoriasis have been published and showed reasonable safety and a modest reduction of disease pathology.  This was a small study (40 patients, 84 days of treatment) that warrants additional evaluation according to Kreuger et al., (2015).   As published results become available, updates will be provided.

Metformin

Metformin is a caloric restriction mimetic.  It is also an FDA approved drug for treatment of T2D. Much is known on how it works to block production of glucose by the liver.  A striking finding was that patients taking metformin for T2D lived longer than those without diabetes and of course not taking metformin.

When used in animals, metformin delays the onset of disease and in some animal models of aging, it extends the lifespan.   It acts in multiple ways to alter nutrient sensing and improve cellular activities related to gene function, recycling of damaged cell components and slowing age-related changes.  These changes mirror those produced by lifelong CR. 

To further understand the caloric restriction mimetic effects of metformin, the FDA (2016) granted approval of its use in a clinical trial to determine whether metformin will delay the onset of disease.  The trial named Targeting Aging with Metformin (TAME) trial will enroll 3000 patients (65-79 years of age) and follow them for 6 years to determine whether metformin delays the onset of major age-related diseases e.g. heart disease, cancer and dementia (https://www.afar.org/tame-trial).  The results are eagerly awaited.

Rapamycin

Rapamycin is an antibiotic and potent immunosuppressant drug to prevent organ rejection.  In animal models of aging including the mouse, treatment with rapamycin extends the lifespan and delays the onset of age-related diseases.  Thus rapamycin is a caloric restriction mimetic.  It acts by inhibiting an important nutrient sensor called mTOR.  This nutrient sensor is activated by insulin.  Therefore, in the presence of rapamycin,  insulin-mediated metabolic effects are significantly reduced. 

Chronic use of rapamycin in man is limited to very low doses due to untoward side effects. However, the Dog Aging Project completed a placebo-controlled trial with 24 healthy companion dogs treated with a low dose of rapamycin for 10 weeks.  The drug is safe and improves cardiac function as determined by an echocardiogram before and after treatment.  Funded by a grant from National Institute of Aging and private donors, the next experiment will enroll a larger number of companion dogs and seek to determine whether aging can be delayed in dogs with this CRM.  

The objective of the Dog Aging Project (dogagingproject.org) is to understand aging in dogs and translate the information to humans.  This is based on observations that humans and dogs share the same environment, they have many biological mechanisms in common and also develop many of the same diseases.  Insights into dog aging should contribute to understanding human aging.

Comparison of diet and mimetics

Common Pathway

The schematic illustrates one known pathway altered by CRMs.  As with CR, these drugs also target the nutrient sensor termed mTOR (mammalian target of rapamycin).  This sensor was uncovered in part with studies using rapamycin.  mTOR is a key protein that affects many other essential pathways in the cell.  When its activity is reduced, more efficient metabolism ensues, recycling is enhanced and inflammation is minimized. The future caloric restriction mimetic will potentially replace dietary caloric restriction.

References of interest

1.  Krueger JG, Suarez-Farinas M, Cueto I et al.  A randomized, placebo-controlled study of SRT2104, s SIRT1 activator in patients with moderate to severe psoriasis. PLoS ONE 10(11): e0142081

2.  Kulkarni AS, Gubbi S, Barzilai N.  Benefits of metformin in attenuating the hallmarks of aging.  Cell Metab 32:  15-30, 2020.

3.  Urfer SR, Kaeberlein TL, Mailheau S.  A randomized controlled trial to establish effects of short-term rapamycin treatment in 24 middle aged companion dogs.  GeroScience 39:117–127, 2017.

Insight 8-Caloric Restriction

Diet, Individual controls aging, , , ,

Importance of caloric restriction (CR)

Previous blogs have focused on specific organ-systems such as skeletal muscle (Insights 2-5) and the brain (Insights 6,7).  Insight 8 describes a proven but difficult path to longevity that impacts ALL organ-systems. This path is one of rigorous caloric restriction. Thus caloric restriction promotes longevity. It is a longevity builder.

Low calorie foods

Not quite a century ago, a Cornell University researcher, Clive McKay who was studying nutrition in rats, reported that rats who ate 30% less calories than those with free access to food, appeared healthier and lived longer than the controls with unlimited access to food.  All rats consumed adequate intake of vitamins, minerals, essential amino acids and fats throughout the study.

Significance of caloric restriction

First, CR is a repeatable experiment. It has been replicated in many different animal models that include yeast, round worms, fruit flies, mice, dogs, and monkeys.  In all studies, CR restriction of 25-30 or more percent produces a significant extension of lifespan with positive effects on a variety of organ-systems.  

Secondly, the CR studies revealed at least one important mechanism of aging. Thus scientists now know that lifespan (at least from yeast to monkey) can be successfully lengthened with reduction in consumption of calories.

Thirdly, CR opened the door to the identification of drug “mimetics” of CR. These new drugs would work like CR but, importantly, bypass the known difficulty for humans to eat less.

Known benefits of caloric restriction

CR produces many benefits in addition to an increase in lifespan.  This has been studied in depth in rodents and monkeys.  Generally, compared to control animals, CR animals exhibit

   (a) a delay in the occurrence of major diseases,

   (b) a delay in the decline in muscle mass,

   (c) a delay in the decline of the immune system, and

   (d) a delay in the decline in some DNA repair mechanisms (protecting cells from random damage). 

Body temperature may decline slightly but overall physical activity in CR animals compared to controls is normal or slightly increased.  Significantly, and considered the driving force behind the above beneficial changes is a shift in how sugars are metabolized.  CR animals utilize new pathways that  reduce the requirement for insulin, a known pro-aging factor.

Results of CR in monkeys

One of the most important studies on CR are the ongoing ones using Rhesus monkeys at the National Institutes of Aging (NIA) and Wisconsin University (Colman et al., 2014; Mattison et al., 2017).  Monkeys began a 30 percent reduction in calories when they were adults.  After 20 years, the number of CR-treated monkeys exceeded that of the controls (survival in the CR group was 80% versus 50% in the control group).  Other benefits, to name a few, include:

   (a) a delay in age-related pathologies such as diabetes, cardiovascular disease, cancer and brain-related disorders;

   (b)  lower blood pressure, heart rate, fasting blood glucose and a favorable lipid profile (low LDL and triglycerides and high HDL);

   (c)  normal levels of testosterone and estrogen, maintenance of “youthful” levels of melatonin (sleep agent) and dihydroepiandrosterone (DHEA popular supplement considered the precursor to hormonal steroids such as estrogen and testosterone);

   (d) maintenance of immune system function (lower levels of inflammatory mediators and higher levels of anti-inflammatory agents); and

   (e) decreased oxidative damage to muscles and decreased onset of sarcopenia (see Insight 2). 

Application of caloric restriction to man

The first study in man was an observational, retrospective and case-controlled study of 18 volunteers (average age ~ 50 years) in self-imposed CR for 3-15 years paired with 18 healthy same age, sex, but eating a western diet (high fats and carbohydrates).  Compared to those eating the western diet, CR individuals had a lower body mass index, less body fat, more lean muscle mass, lower levels of LDL, triglycerides and fasting glucose and insulin and higher HDL and lower levels of a key inflammatory mediator, C-reactive protein (Fontana et al., 2004).

NIA sponsored the clinical trial, CALERIE = (Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy) Study  which has completed several small (~50 volunteers) phase I trials of 6 months to 1 year duration and a larger (218 volunteers) phase II trial that lasted 2 years.  In both phases the target caloric reduction was a minimum of 25% but in phase I, individuals achieved a 10-17% caloric reduction and in the longer trial, only a 12% caloric reduction was achieved.  Even with this modest CR, there were positive changes such as decrease in fasting glucose, decrease in inflammatory makers, improved cell function and decrease in cardiovascular risk factors.  However, the CR reduction was too modest and phase II too short to achieve the milestones evident in the monkey studies.

Caloric restriction – next steps

The difficulty for humans to adhere to a 30% reduction in calories has ushered in interest in developing drugs to “mimic” CR.  As the thinking goes, in the future, individuals will be able to take a drug that mimics CR and also be able to eat whatever is desired.  Three candidate drugs have been proposed:

a) metformin

b) rapamycin

c) sirtuins

A discussion of these 3 compound will be the topic of my next blog.

References                          

Fontana et al.,  Proc Natl Acad Sci USA 101:  6659-63, 2004.

Colman et al., Nat Commun 5:  3557, 2014

Mattison et al., Nat Commun. 8:  14063, 2017.

Insight 5 – Optimizing Balance

Exercise, Individual controls aging, , , , ,

Benefits of a stable balance

Good Balance

Good balance is absolutely essential to prevent falls.  Reliable balance also assures an optimal comfortable walking pace.  Results of clinical trials tells us that strength and balance exercises will definitely help us avoid falls and get us safely from point A to point B.  In other words, you can minimize your risk of falling and improve your walking pace through a proven exercise program (given below).  On the other hand, ignoring these exercises will guarantee a high risk of falling and bring on an abundance of unwanted consequences.

Balance depends on biology that changes with age

Balance deteriorates with age.  There are many reasons for this.  Firstly, declining sight and hearing contribute to poor balance.  Secondly, years of poor posture exacerbated by weak back muscles and loss of bone mass produce a compressed spine or a “hunched” back that reduces upright stability.  Thirdly, the sense of touch and the sense of muscle/joint position decline and hence need to be retrained.  Reduced sight and hearing may be readily improved with correctives lenses and hearing devices but sadly these are often ignored.  Other decrements are best minimized through resistance and balance exercises.  Age-associated decline in balance is modifiable; modifications will definitely build longevity by lengthening the health span.

The cost of a fall is high

Approximately thirty percent of elderly fall at least once a year.  Avoiding a fall is of paramount importance because the consequences of a fall are all negative.  The least negative might be a sore muscle but more commonly, it is a broken bone e.g. hip.  Broken bones require hospitalization, medical expenses, and significant recovery time that limit independence.  Hip fractures are especially harmful since they are associated with an elevated risk of dying, a risk which persists for years after the fracture.  Another outcome after a fall is onset of an unavoidable psychological mentality called “fear of falling”.  This plays a role in producing a slower, more cautious gait that unfortunately is incredibly damaging in the long run. 

The cost of slowed gait is high

Poor balance leads to an unsteady, hesitant walking gait.  This compromises posture and reduces further the existing poor balance.  This downward cycle favors a fall.  Slowed gait also limits mobility and independence.  Performance of daily tasks take more time and therefore, become more difficult.

Balance exercises are part of the 4-Prong Exercise Program

Previous blogs discussed progressive resistance exercises, aerobic exercises, and stretch exercises.  Additionally they discussed the validity of these exercises to modify various age changes, to increase the health span and to build longevity.  The final essential exercise to add to the preceding 3 is balance.   Balance exercises are critically important for retraining the sensory perception pathways in the joints and muscles of the feet, ankles, legs.  Balance exercises need to partner with specific resistance exercises to be totally effective in optimizing balance and preventing falls. 

Evidence to show balance exercises works

Results of several clinical trials provide evidence that specific balance exercises coupled with moderate intensity lower limb resistance exercises improve balance stability and reduce the risk of falling.  These trials (both sexes, community dwellers, 65 years and older, one study with women with osteoporosis) employed several standardized tests to measure balance before and after the interventions (resistance and balance exercises for 6-12 months) and traced the incidence of falls in the control and exercising groups.   

Exercises to improve balance; balance type

Here are the balance exercises used in the clinical trials mentioned above.  Balance exercises are initially practiced for 10 seconds and increased over time.  The more practice, the better the improvement in balance.

(1) standing with one foot directly in front of the other;

(2) walking placing one foot directly in front of the other;

(3) walking on heels;

(4) walking backwards, sideways and turning around;

(5) stepping over objects;

(6) bending and picking up an object;

(7) stair climbing in the home;

(8) rising from a sitting position to a standing one;

(9) knee squat.

Exercises to improve balance; resistance type

Here are the resistance exercises used in the clinical trials noted above and shown to be successful in improving balance in the elderly and decreasing risk of falling.  They are the (1) hip extensor, (2) hip abductor, (3)  knee extensor, (4) knee flexor, (5) inner quadriceps, (6) ankle plantar and (7) dorsiflexor muscle exercises.  These exercises are fairly simple to do and are described below.  They should be initiated without ankle weights and one set of 10 repetitions.  When ready, add an ankle weight of 1 pound and progress up to 6 pounds; increase the number of sets.   The greater the weight and the number of sets, the better the improvement in balance. The combination of  balance and resistance exercises are performed a minimum of 3 times a week for approximately 30 minutes.

Specific resistance exercises proven to improve balance

1.  Hip Extensor

     stand 12-18 inches from table

     bend at hips: hold onto the table

     slowly lift one leg straight backwards; hold position

     slowly lower leg

     repeat with other leg

2.  Hip Abductor

     stand near table; hold onto table

     move straight leg sideways away from body; hold position

     slowly lower leg

     repeat with other leg

3.  Knee Extensor

     sit in a chair with your back and hips against back of chair.

     keep knees at 90 degree angle, resting toes on ground

     in a 1-2 up count,  extend your left leg straight out parallel to the ground

     pause for 1 second

     in a 1-2-3 down count, slowly lower your leg back to 90 degrees

4.  Knee Flexor

     stand behind chair, resting hands on back of chair, facing forward, keep head in line with spine, place feet shoulder-width apart, pelvis level with knees slightly bent

      in a 1-2 up count, bend left leg to bring up heel toward buttocks as high as possible

      pause for 1 second

      in a 1-2-3 down count, lower left heel to ground

5.  Inner Range Quadriceps

     sit on ground with knee bent over a rolled up towel

     tighten up knee muscles and lift heel off ground; keep knee on rolled up towel

     hold for 5 seconds, getting heel as high as possible

     start with large rolled up towel and gradually decrease size of roll

6.  Ankle Dorsiflexor

     sit on chair with feet touching floor

     leave heel on floor and tap toes up and down

     Alternative – using elastic stretch band of comfortable resistance

     sit on the floor with legs straight out in front

     anchor elastic band to a chair or table leg and wrap around foot

     pull toes toward you and slowly return to start position

7.  Ankle Plantar Flexion

     sit on chair with feet touching floor

     leave toes on floor and lift heel up and down

     Alternative with elastic band

     wrap elastic band around foot and hold the ends in your hands

     gently point toes and slowly return to start position