Tag Archives: exercise

Elders on a Weight-Loss Diet Preserve Bone Mineral Density With Resistance Training, Not Aerobic Exercise

according to an article at MedPageToday.

"One more rep then I'm outa here!"

“One more rep then I’m outa here!”

In the study at hand, the two experimental groups had about 60 participants each, so it was a relatively small study. (In general, the larger the study, the more reliable the findings.) Most participants were white women; mean age was 69. The experimental intervention ran for five months. An excerpt:

In one trial, the participants were randomized to a structured resistance training program in which three sets of 10 repetitions of eight upper and lower body exercises were done 3 days each week at 70% of one repetition maximum for 5 weeks, with or without calorie restriction of 600 calories per day.
In the second study, participants were randomized to an aerobic program which was conducted for 30 minutes at 65% to 70% heart rate reserve 4 days per week, with or without calorie restriction of 600 calories per day.

The beneficial bone effect was seen at the hip but not the lumbar spine. (I’ve treated lots of hip and lumbar spine fractures. If I’m going to break one of those bones, I’d rather it be the spine.)

Thin old bones—i.e., osteoporotic ones—are prone to fractures. Maintaining or improving bone mineral density probably prevents age-related fractures. In a five-month small study like this, I wouldn’t expect the researchers to find any fracture rate reduction; that takes years.

Most mainstream articles on prevention and treatment of osteoporosis mention “weight-bearing” exercises as what you should do, like walking, jogging, tai chi, and volleyball. The current study adds resistance training to our therapeutic armamentarium. Resistance training is also called weight training or strength training.  

Most elders starting a weight-training program should work with a personal trainer.

Steve Parker, M.D.

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QOTD: Exercise versus Death

What fits your busy schedule better, exercising 30 minutes a day or being dead 24 hours a day?

—Randy Glasbergen in a 2008 cartoon

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A Review: “Stop the Clock: The Optimal Anti-Aging Strategy”

dementia, memory loss, Mediterranean diet, low-carb diet, glycemic index, dementia memory loss

“I wish we could have read PD Mangan’s book thirty years ago!”

I read P.D. Mangan’s 2015 book, Stop the Clock: The Optimal Anti-Aging Strategy. I give it five stars in Amazon’s rating system. High recommended.

♦   ♦   ♦

I approached this book with trepidation. I like PD Mangan even though I’ve never met him. We’ve interacted on Twitter and at our blogs. You can tell from his blogging that he’s very intelligent. I don’t know his educational background but wouldn’t be surprised if he has a doctorate degree. My apprehension about the book is that I was concerned it would be brimming with malarkey and scams. Fortunately, that’s not the case at all.

Twin studies have established that 25% of longevity is genetic. That leaves a lot of lifestyle factors for us to manipulate.

I’m not familiar with the anti-aging scientific literature and don’t expect it will ever be something I’ll spend much time on. But it’s an important topic. I’ll listen to what other smart analysts—like Mr. Mangan—have to say about it.

It’s quite difficult to do rigorous testing of anti-aging strategies on free-living humans. So the best studies we have were done with worms, rodents, and monkeys; the findings may or may not apply to us. For example, long-term calorie restriction—about 30% below expected energy needs—is known to prolong life span in certain worms and rodents, with mixed results in rhesus monkeys. It’s the rare person who would follow such a low-calorie diet for years as an experiment. I doubt I would do it even if proven to give me an extra five years of life. I like to eat.

There are several prominent theories of how and why animals age. The author thinks the major factors are:

  1. oxidative stress
  2. inflammation
  3. a decline in autophagy (perhaps most important)

An effective anti-aging program should address these issues.

In the anti-aging chapter of his book, The South Asian Health Solution, internist Ronesh Sinha says that “Lifestyle practices that reduce excess inflammation in the body will help delay the aging process.” Dr. Sinha is a huge exercise advocate and low-carb diet proponent.

Mr. Mangan makes a convincing argument that a good way to forestall aging is to apply hormetic stress. Hormesis is a phenomenon whereby a beneficial effect (e.g., improved health, stress tolerance, growth, or longevity) results from exposure to low doses of an agent or activity that is otherwise toxic or lethal when given at higher doses.

Needs a bit more hormetic stress

Needs a bit more hormetic stress

In case you’re not familiar with hormesis, here’s a major example. Lack of regular exercise leads is linked to premature death from heart disease and cancer. Starting and maintaining an exercise program leads to greater resistance to injury and disease and longer life span. On the other hand, too much exercise is harmful to health and longevity. We see that in professional athletes and excessive marathon runners. Something about exercise—in the right amount—enhances the body’s intrinsic repair mechanisms. That’s the hormetic effect of exercise; one mechanism is by turning on autophagy.

Autophagy is the body’s natural process for breaking down and removing or recycling worn-out cellular structures. This wearing-out occurs daily and at all ages.

If you’re thinking Mr. Mangan recommends exercise as an anti-aging strategy, you’re exactly right. Especially resistance training and high intensity training. His specific recommendations are perfectly in line with what I tell my patients.

Calorie restriction is another form of hormesis; the body reacts by up-regulating stress defense mechanisms. As a substitute for calorie restriction, the author recommends intermittent fasting. Intermittent fasting increases insulin sensitivity, which leads to enhanced autophagy. Fasting seems perfectly reasonable if you think about it, which very few do. Many of us eat every three or four hours while awake, whether a meal or a snack. If you think about it, that’s not a pattern that would be supported by evolution. In the Paleolithic era, we often must have gone 12–16 hours or even several days without food. Hominins without the resiliency to do that would have died off and not passed their genes down to us.

Steve Parker MD, Advanced Mediterranean DIet

Naturally low-carb Caprese salad: mozzarella cheese, tomatoes, basil, extra virgin olive oil

Another anti-aging trick is a low-carb diet, defined as under 130 grams/day, or under 20% of total calories. It may work via insulin signaling and weight control.

Glutathione within our cells is a tripeptide antioxidant critical for clearing harmful reactive oxygen species (free radicals). We need adequate glutathione to prevent or slow aging. Cysteine is the peptide that tends to limit our body’s production of glutathione. We increase our cysteine supply either through autophagy (which recycles protein peptides) or diet. Dietary sources of cysteine are proteins, especially from animal sources. Whey protein supplements and over-the-counter n-acetyl cysteine are other sources. Fasting is another trick that increases cysteine availability via autophagic recyling.

I don’t recall the author ever mentioning it, but if you hope to maximize longevity, don’t smoke. Even if it has hormetic effects. Maybe that goes without saying in 2015.

When I read a book like this, I always run across tidbits of information that I want to remember. Here are some:

  • those of us in the top third of muscular strength have a 40% lower risk of cancer (NB: you increase your strength through resistance training not aerobics)
  • exercise helps prevent cognitive decline and dementia, at least partially via enhanced autophagy
  • exercise increases brain volume (in preparing to do this review I learned that our brains after age 65 lose 7 cubic centimeters of volume yearly)
  • optimal BMI may be 20 or 21, not the 18.5-25 you’ll see elsewhere (higher BMI due to muscle mass rather than fat should not be a problem)
  • Scientist Cynthia Kenyon: “Sugar is the new tobacco.” (in terms of aging)
  • phytochemicals (from plants, by definition) activate AMPK, a cellular energy sensor that improves stress defense mechanisms and increases metabolic efficiency
  • curcumin (from the spice turmeric) activates AMPK
  • coffee promotes autophagy
  • he does not favor HGH supplementation
  • in the author’s style of intermittent fasting, you’re not reducing overall calorie intake, just bunching your calories together over a shorter time frame (e.g., all 2,500 calories over 6-8 hours instead of spread over 24)
  • mouse studies suggest that intermittent fasting could reduce risk of Alzheimer’s disease and Parkinsons disease
  • consider phytochemical supplements: curcumin, resveratrol, green tea extract
  • calorie-restriction mimetics include resveratrol, curcumin, nicotinamide, EGCG, and hydroxycitrate
  • supplemental resveratrol at 150 mg/day improved memory and cognition in humans

The author provides very specific anti-aging recommendations that could be followed by just about anyone. Read the book for details. Scientists are working feverishly to develop more effective anti-aging techniques. I look forward to a second edition of this book in three to five years.

Steve Parker, M.D.

PS: People with certain medical conditions, such as diabetics taking drugs that can cause hypoglycemia, should not do intermittent fasting without the blessing of their personal physician. If you have any question about your ability to fast safely, check with your doctor.

PPS: If you have diabetes or prediabetes and want to reduce your carbohydrate consumption, consider my Low-Carb Mediterranean Diet or Paleobetic Diet.

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Preserve Your Hippocampus With Exercise

MRI scan of brain

MRI scan of brain

The NYT’s Well blog has the details. The brain’s hippocampus is a critical center for memory. Alzheimers disease is associated with a gene called apo-E4. Carriers of that gene who exercise regularly have less shrinkage of the hippocampus than non-exercisers.

To PROVE that regular exercise prevents dementia-related shrinkage of the hippocampus, you’d have to force some folks to exercise and stop others who wanted to exercise. A couple years later, scan their brains and compare the two groups. That study may never be done.

The Mediterranean diet also seems to prevent or forestall dementia.

Steve Parker, M.D.

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QOTD: Exercise and Weight Loss

Let me be clear. Exercise is not important because it burns calories! Exercise without calorie restriction is a remarkably ineffective weight loss intervention, because it usually makes us hungry enough to replace the calories we burn. Exercise is important because it restores your ability to oxidize fat—both when fasting and after meals. And we can tie this in with mitochondrial dysfunction by noting that exercise is proven to increase mitochondrial volume.

J. Stanton

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Preserve Your Brain Function Despite Aging

There are ways of slowing or reversing losses in cognitive function. The most effective discovered so far is physical exercise, which protects the brain by protecting the body’s cardiovascular health. Mental exercise, often called brain training, is widely promoted, but it boosts only the particular skill that is practised – its narrow impact mirroring that of educational interventions at other ages. Various drugs are being investigated for their value in staving off normal cognitive decline, but for now preventive maintenance is still the best bet – avoid smoking, drinking to excess, head injuries and the like.

MRI scan of brain

MRI scan of brain

The quote above is from an Instant Expert paper on intelligence. It’s full of interesting facts such as the typical difference in IQ between strangers is 17 points. It answers the question whether an enriched school or home environment can increase intelligence.

Also, for preserving brain function, I think the Mediterranean diet helps, but it’s difficult to prove.

On a different note, the article mentions overload of patients’ brains when medical care is too complicated:

Given the complexity of self-care regimes, it is hardly surprising that some people make dangerous errors or fail to comply. The effective management of diabetes, for example, requires a person to keep blood sugar levels within a healthy range, which means coordinating diet, exercise and medication throughout the day, which in turn requires planning for contingencies, recognising when blood sugar is veering too high or low, knowing how to regain control and conceptualising the imperceptible but cumulative damage caused by failing to maintain control. There is no set recipe for people with diabetes to follow – their bodies and circumstances differ. Moreover, they get little training, virtually no supervision and no days off. Effectively managing your diabetes is a cognitively complex job and poor performance has serious consequences, including emergency room visits, lost limbs or eyesight, and even death. The lower the diabetic person’s IQ, the greater the risks.

You’ll also learn about the Flynn effect and possible explanations for it:

Over the past century, each successive generation has answered more IQ test items correctly than the last, the rise being equivalent to around 3 IQ points per decade in developed nations. This is dubbed the “Flynn effect” after the political scientist James Flynn, who most thoroughly documented it. Are humans getting smarter, and if so, why? 

I’m more inclined to think Idiocracy describes our future.

Steve Parker, M.D.

h/t James Fulford

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Yet Another Reason to Exercise as You Get Older

Compared to others, elderly type 2 diabetics are more afflicted with lower leg muscle mass, leg strength, and functional capacity. Click for details.

The right exercise program can counteract these problems and improve quality of life.

Steve Parker, M.D.

h/t Bill Lagakos

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