среда, 2 ноября 2011 г.

How Maintaining Muscle Mass Contributes to Longer Life

How Maintaining Muscle Mass Contributes to Longer Life
How Maintaining Muscle Mass Contributes to Longer Life

Traditionally, the muscle function has been discussed in the context of movement. Muscles allow us to walk, run, and jump. They help us move our eyes, breathe, chew and swallow food, circulate our blood, empty our bowels and bladder, lift and push objects, and they keep us upright. This is what we’ve all been taught since our first elementary science or health class, and it’s what students are taught in medical schools.


You may not be aware, though, that muscle has several functions separate from body movement. In fact, the amount of muscle mass you have can actually help determine your ability to prevent disease, recover from illness, and live the longest life possible.


Readers of my newsletter Alternatives know why I believe sarcopenia (the medical term for loss of muscle mass) will soon become one of the most common health problems facing our elderly. Those in the pharmaceutical industry have recognized this likelihood, as well. As one industry research consultant stated, “There’s a lot of interest in trying to come up with something for sarcopenia because at the moment, there’s no treatment.”


That’s the typical pharmaceutical mindset. If there’s no drug on the market, then there’s no form of treatment available. Wrong.


There is a way to naturally preserve and promote muscle growth and function: Weight-bearing or resistance exercise. Every single person should incorporate this type of exercise into his or her daily activities—not to get “cut“ or have the proverbial six-pack abs, but because of the unrecognized benefits that healthy muscle provides.


Muscle Mass Regulates Blood Sugar


Muscle tissue is a huge metabolic organ. Because it is almost always in a state of tension, it requires energy in the form of glucose (blood sugar). Through its constant consumption of glucose, muscle can be a major regulator of blood sugar. (Appl Phys Nutr Metab 14;39(9):987–97) (J Nutr 11 Apr 1;141(4):568–73)


Having adequate muscle tissue can act as a buffering mechanism to help your body cope with the surge in glucose that occurs after meals. Additionally, increasing your muscle mass as you age is one way to prevent type 2 diabetes. It’s no coincidence that the rate of diabetes begins to rise around the same time that muscle mass typically starts to decline.


Muscle Mass Boosts the Immune System


Muscle tissue is also the only place where your body can store amino acids. While we typically credit amino acids as the building blocks of protein, they have a crucial role in proper immune system function.


Amino acids such as glutamine, arginine, and cysteine play a part in how effectively the immune system produces antibodies and responds to pathogens and toxic compounds. When you suffer muscle loss, your body loses its amino acid storage facility. The unavailability or deficiency of amino acids weakens your immune system, makes you more susceptible to opportunistic infections, and impairs your body’s ability to fight off these attacks. We see this repeatedly in the elderly and hospitalized patients, both of whom have a much greater risk of contracting and dying from almost every communicable disease. This is also one of the primary reasons mortality rates are so much higher in the elderly and frail during various epidemics. (Crit Care Med 90 Feb;18(2 Suppl):S86–93) (Br J Nutr 07 Aug;98(2):237–52)


As you recall, the largest immune organ in the human body is comprised of the lymphatic tissue that lines the intestinal tract and colon. Amino acids are not only necessary for the growth and integrity of the gastrointestinal lining, they provide the energy for immune cells such as lymphocytes, neutrophils, and macrophages. (Am J Physiol 95 Feb;268(2 Pt 2):R334–42)


Maintaining adequate muscle mass helps give your immune system the necessary compounds it needs to save your life. Unfortunately, you likely won’t see anyone suggesting that you consume more amino acids, or stressing the importance of maintaining muscle mass even during flu season.


Although recommending that the public take a couple of scoops of amino acid-rich whey protein each morning would probably be one of the best things they could do to get through the flu season unscathed, the powers that be continue to push the latest flu vaccine. Yet decades of research confirms that flu vaccines have few, if any, benefits.


The key to preventing flu and other illnesses is to keep your immune system running at peak efficiency—and to do that, you need to maintain muscle mass and amino acid reserves.


Muscle Loss = More Falls


In addition to affecting immunity, lack of muscle leads to a greater risk of falls. Falls are the leading cause of death due to injury among the elderly, and 87 percent of all fractures in the elderly are caused by falls. In older people who fall, 40 percent never return to independent living and 25 percent die within a year.


This particular subject hit home when my mother fell. She’s in her late 80s and tripped while taking out the garbage. She broke her hip but is recovering extraordinarily well since a great deal of her rehab program focuses on increasing muscle strength. I can’t help but think she might not have experienced this fall if she had prioritized the building of muscle mass in the past. (In fairness to my mom, I’m sure I could have avoided a lot of issues in my life had I listened more carefully and followed her advice.)


Although at this point the research on muscle mass and its effects on health has focused mainly on falls, immunity, and a few other areas, it obviously influences our health in ways we have yet to discover.


Healthy Muscle Mass Can Lower Risk of Death


In one of the most interesting studies I’ve seen in a long time, researchers found that muscle strength alone (determined by handgrip and knee extension tests) in those under 55 years of age was associated with a 20–30 percent lower risk of all causes of death (except cancer), independent of body mass index or blood pressure. (BMJ 12 Nov 20;345:e7279)


Older people with the weakest grip strength are more likely to die in the following few years, compared to individuals in similar health. (J Epidemiol Community Health 14;68(7):663–8) (BMJ 10 Sep 9;341:c4467) (J Nutr Health Aging 12;16(9):769–74)


You don’t need to become a professional bodybuilder or weightlifter, but it does take more than a television remote to build your grip strength.


If you don’t have access or the knowledge to use traditional weights, there are lots of other inexpensive ways to begin adding strength and muscle mass. Elastic bands and/or cords are probably the most affordable, easiest to use, and most readily available tools that can be used by anyone of any age. They provide resistance and simulate the effects of weights. You can find them online and at stores such as Walgreens or Wal-Mart.


It’s important to take simple steps to maintain your muscle mass regardless of whether you’re a 50-year-old sedentary office worker or a retired grandmother. One thing is certain: If you’re not actively exercising to preserve or boost your muscle mass, it’s being lost. And as you gradually but surely lose muscle, you are compromising your immune system, raising your risk of developing diabetes and cardiovascular disease, jeopardizing your future ability to live independently, and increasing your risk of dying prematurely.


Don’t Fall for the Scary Sales Pitch


If I were trying to sell you something, this would probably be the perfect, scary sales pitch.


Over the next decade, I suspect you’ll start to see a huge advertising blitz highlighting the need to treat and manage sarcopenia. There will be a lot of discussion about mitochondria—the little organelles or “energy generators” that reside in each cell. Mitochondria combine oxygen and nutrients to create fuel for cells.


Mitochondria sort of operate on their own, independently from the rest of the cell. They have their own DNA and repair systems and multiply on their own. Over time, their genetic material mutates and the number of mutations overwhelms their ability to make necessary repairs. As a result, mitochondria start to malfunction and die. In the process, muscle cells shrink and die. Many in the scientific community think this is the underlying cause of aging.


The pharmaceutical industry is working on drugs that counteract the damage from mutations and help preserve mitochondrial function. We’ve seen similar situations time and time again with drugs to reduce cholesterol, increase bone density, and so on. In every case, the results are underwhelming and the side effects very often outweigh the benefits. Changing and artificially manipulating body chemistry can have miraculous effects in the short term. And it can definitely be a godsend in emergency situations. But long-term manipulation, or what the pharmaceutical industry now calls “managing a disease,” isn’t always so advantageous (at least to the patient anyway).


You probably won’t be told just how effective exercise can be at counteracting mitochondrial aging.


Canadian researchers recently studied the effects of exercise on specially bred mice that lacked the ability to repair their mitochondria. By the time they were three months old (the human equivalent of age 20), their mitochondria were already malfunctioning. At eight months (age 60 for humans), they were very frail and decrepit. Their muscles were thin and flaccid, their hearts were enlarged, their hair gray, thin, and balding, and their brains and sex organs shrunken and shriveled. None of the mice reached one year of age.


A corresponding group of these same mice, however, were allowed to run on an exercise wheel 45 minutes a day, three times a week starting at three months old. Each session was roughly equivalent to a person running six miles in just under an hour. These mice exercised for five months.


At eight months old, the difference between the two groups was astounding. The exercising mice were youthful. Their pelts were dark, without any gray. They had maintained all their muscle mass and brain volume. Their hearts and sex organs were totally normal, and their ability to balance and exercise was retained. In fact, none of the mice had died of natural causes.


When they were examined, they had more mitochondria overall, and the mitochondria had far fewer mutations than those in the sedentary group—despite the fact that genetically, the exercising mice still lacked the capability of mitochondrial repair. (Proc Natl Acad Sci U S A 11 Mar 8;108(10):4135–40)


Exercise Can Reverse Mitochondrial Aging 15-20 Years


Dr. Mark Tarnopolsky, one of the lead researchers who has performed several similar studies, commented that, although the exercise was pretty strenuous, this high level of exertion isn’t necessary to achieve benefits.


If you haven’t exercised at all, Dr. Tarnopolsky recommends that you start by walking five minutes a day, and gradually increase your activity level as you become more fit. To maximize benefits, it’s best to combine endurance training with resistance exercise. Resistance/strength training, in particular, appears to trigger muscle stem cells called satellite cells, which seem to rejuvenate mitochondria. Researchers refer to the phenomenon as “gene shifting,” which is thought to be responsible for turning back the biochemical, physiological, and genetic signature of older muscle by 15 or 20 years after regular strength training or weightlifting. (Hum Mol Genet 99 Jun;8(6):1047–52)


The actual exercise threshold necessary to obtain anti-aging benefits hasn’t been established, but we know other studies have confirmed that both moderate endurance exercise, as well as weightlifting, can provide these same effects.


Obviously the sooner you start, the better. Studies show that lifelong exercisers have the mitochondrial function of individuals half their age. Athletic 80-year-old men have the aerobic and mitochondrial function comparable to that of non-endurance trained men 40 years younger. (J Appl Physiol 13 Jan 1;114(1):3–10)


Tissues such as bone and muscle grow in response to mechanical stress placed on the body. It’s all part of a complex adaptation process where the body responds to a change in its physical environment. Trying to artificially trigger those changes with drugs, especially on a continual basis, will be a disaster in the making. Why take the risk when we know the right types of exercise combined with the consumption of quality protein and amino acids are all that you need?


Original article and pictures take s3.amazonaws.com site

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