Tuesday, January 21, 2014

Aging with beauty

image: LaterBloomers
“Every man desires to live long, but no man would be old.”
(Irish satirist Jonathan Swift)

Getting older? Me too! Those of us lucky enough to reach our golden years will get to experience the gradual decline in muscle mass and function that come with surviving middle age. Oh boy.

It turns out that much of the loss of strength, speed, and overall fitness in older people appears to be tied as much to a combination of reduced activity and weight gain as to aging itself. They go together: we get busy and exercise less, we get tired and exercise less, and we get out of the habit and exercise less. And repeat. Then we find we are out of shape, and it’s a whole lot harder to get moving again.

In fact, a scientific study that compared the effects of extreme inactivity to aging showed that study participants had lower aerobic fitness after 3 weeks of bed rest at age 20 than they did when re-tested 30 years later.

So it makes sense that study after study is revealing that getting and staying active fights aging in a powerful way, benefitting both our bodies and our brains, and continuing to exercise vigorously as we age may help us to maintain speed and fitness longer than previously understood.

Strength & speed (bones and muscles)

Sarcopenia is the term used to describe the loss of muscle mass and associated weakness and decreased coordination as we age.

We start losing muscle mass after about age 50, at an annual rate of 1-2%, eventually losing up to 50%, which can explain the decreased athletic performance as we age. Starting even earlier, fast-twitch muscle fibers are gradually converted to slow-twitch fibers (called motor unit restructuring), which decreases muscle strength and makes our movements less powerful and precise.

our bones gradually lose density,
which is why falls cause more injuries in older adults
image: Physioworks
Muscles are made up of proteins, and since our bodies don’t perfectly replicate every new protein, we gradually lose some muscle functioning.

Two growth hormones and the hormone testosterone, which all help produce and synthesize protein, decline by about 1% per year after the age of 40. The loss of these hormones is linked to a loss of protein and a decline in both muscle mass and bone density.

Men have a lower risk of osteoporosis (“thin bones”) than women, though they, too, lose bone calcium as they age, increasing the risk of fractures.

Show resistance

People of all ages can build muscle size and strength through resistance training, but older people need to maintain their workout frequency and intensity more than younger ones if they want to maintain muscle mass.

Sounds unfair, right? It is.

GoFigure today looks at the trend in excercise as it relates to age.
image: LiveScience

Don't despair. Since studies in the 1990s began showing the gains made by older adults from resistance training, it has become the exercise program of choice for this age group. And the benefits accrue, even if you are 102. Here's a great example:

These two bodybuilders and personal trainers are Bill Cunningham (73) and
Jane Hesselgesser (68), and their impressive physiques show the power of
resistance training for older athletes.    photo: Rick Rickman

And a slightly more modest but equally inspiring one:

Sandy Palais (73) started training to build bone mass to beat
osteoporosis and ended up building muscle as well
photo: Jason Millstein, NPR

Help your heart and train your brain

Age-related changes to other systems -- especially our circulatory and nervous systems -- are equally dramatic (and improved by exercise).

For example, as early as our late 20’s (!!), our heart’s peak capacity to pump blood declines by 5%–10% per decade. No wonder we get more winded as we age: a healthy 25-year-old heart can pump over 2 liters (2½ quarts) of oxygen a minute, but a 65-year-old heart can pump no more than 1½ quarts, and even a healthy 80-year-old heart can pump only about a quart.

On top of that, in middle age, the heart begins to stiffen and shrink, and it has to work harder because blood vessels lose flexibility and the blood itself thickens. The lower movement of new oxygenated blood to your muscles decreases your aerobic capacity and can make you tired and breathless after even modest activity.

better than crossword puzzles
image: YouCanBeatMS
Regular exercise helps to slow age-related weakness of muscles and circulation at any point, though the earlier one starts, the better. A test of former top-flight cross-country skiers older than 80 found that their cardiovascular fitness was “comparable to non-endurance-trained men 40 years younger.” All nine athletes had strong, well-conditioned hearts from years of aerobic exercise.

Even the brain starts to shrink in our later years (is that what that jiggling sensation is?), and scientists link the change in size to a similar decline in brain activity, particularly a loss of memory. Several studies of exercise have found that:
  • people in their 70s who stayed active tended to have larger brains than those who didn’t.
  • inactive older adults that began a walking program had larger hippocampus regions (involved with memory) one year later than a similar group that began a stretching and toning program.
  • physical exercise, more than mental stimulation, such as doing crossword puzzles, maintains the brain’s size and, presumably, one's memory capacity.
  • studies with mice have shown that exercising regularly helped both young and older laboratory rats to improve their spatial memory and cognitive performance (perception, reasoning, and judgement). Good ol' mice!

image: CrankyFitness

Not everyone can or wants to do resistance training, and experts agree that sticking to an exercise program is half the battle. If you love a particular exercise and will do it regularly, that suggests you should keep it up. I love to run in Bangkok’s Lumpini Park to watch the many groups of (usually older) people doing various tai chi routines – some use props like fans or swords, and many wear their group uniform. They are out most mornings.

Taichi in the park - Picture of Lumpini Park, Bangkok
tai chi in Bangkok's Lumpini Park -- we run past this crew in the mornings
photo: courtesy of Trip Advisor

For the more competitive or those looking to test their skills, there is masters swimming, tennis tournaments with senior age categories up to 80 & Over (90+ in a few!), and the Senior Games ("senior olympics"). The inspiring documentary “The Age of Champions” follows several senior olympians through their trials and successes. Here's a peak:

My takeaway message from all my research for this post?

“It is never too late to harness our body’s capacity to get stronger and more functional,” she says. “There is no pill that can do what exercise does.”

For more information on strength training and exercise while aging

Some more inspiring fitness gains by seniors, including the author (ok, he's 55)

Strength training for those just starting out at Cranky Fitness

Harvard Medical School's article on exercise and aging;, which includes this table of the many reasons to exercise and avoid getting old!

Using your body will keep it young (table from Harvard Medical School).

Exercise vs. aging

Effect of agingEffect of exercise
Heart and circulation
Resting heart rateIncreaseDecrease
Maximum heart rateDecreaseSlows the decrease
Maximum pumping capacityDecreaseIncrease
Heart muscle stiffnessIncreaseDecrease
Blood vessel stiffnessIncreaseDecrease
Blood pressureIncreaseDecrease
Number of red blood cellsDecreaseNo change
Blood viscosity (“thickness”)IncreaseDecrease
Maximum oxygen uptakeDecreaseNo change
Speed of emptyingDecreaseIncrease
Calcium content and strengthDecreaseIncrease
Muscle mass and strengthDecreaseIncrease
Metabolic rateDecreaseIncrease
Body fatIncreaseDecrease
Blood sugarIncreaseDecrease
Insulin levelsIncreaseDecrease
LDL (“bad”) cholesterolIncreaseDecrease
HDL (“good”) cholesterolDecreaseIncrease
Sex hormone levelsDecreaseSlight decrease
Nervous system
Nerve conduction and reflexesSlowerDecrease
Quality of sleepDecreaseIncrease
Risk of depressionIncreaseDecrease
Memory lapsesIncreaseDecrease

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