By Dr. Mercola
Researchers have discovered that exercise affects the behavior of your muscle stem cells.i
This finding could lead to new rehabilitation techniques for muscle injuries, and may help prevent or even restore age-related muscle loss.
It has long been known that mesenchymal stem cells (MSCs) in skeletal muscle are an important part of the muscle repair process.
According to lead author Marni Boppartii:
"Since exercise can induce some injury as part of the remodeling process following mechanical strain, we wondered if MSC accumulation was a natural response to exercise and whether these cells contributed to the beneficial regeneration and growth process that occurs post-exercise."
They concluded that MSCs in muscle are very responsive to mechanical strain, and that these stem cells do accumulate in muscle post exercise.
And while the MSCs don't directly contribute to building new muscle fibers, they do release growth factors, which encourage other cells to generate new muscle.
Preliminary data suggest people's muscles tend to become increasingly deficient in MSCs with advancing age, so the researchers hope to develop a therapy that combines exercise with stem-cell-based strategies to prevent age-related muscle loss.
According to Professor Boppart:
"Although exercise is the best strategy for preserving muscle as we age, some individuals are just not able to effectively engage in physical activity. Disabilities can limit opportunities for muscle growth. We're working hard to understand how we can best utilize these cells effectively to preserve muscle mass in the face of atrophy."
For the rest of us, this finding may offer renewed inspiration to get moving; and especially to incorporate strength training throughout your life, regardless of your age. After all, without muscle strength, movement becomes difficult. And impaired movement can suck a lot of the joy out of your life...
Stem Cells Offer Powerful Potential in Anti-Aging Medicine
I believe many stem cell therapies will be a major part of the future of medicine, especially anti-aging medicine. The beauty with adult stem cells is that you're less likely to need dangerous immunosuppressive drugs as there's little risk of rejection when using your own adult stem cells.
What makes stem cells so special is their potential to develop into many different cell types. When a stem cell divides, it either becomes another type of cell, such as a muscle cell or brain cell, or it remains a stem cell. Further, these cells act as an internal repair system in many types of tissues, dividing a seemingly infinite number of times to replenish other cells. If stems cells can be directed to turn into specific cell types, they could offer an ongoing source of replacement to cells and tissues, and be used to treat diseases such as:
Alzheimer's disease Spinal cord injury Stroke Heart disease Osteoarthritis and rheumatoid arthritis Burns
However, as you age, your stem cells begin to diminish in quality and quantity, so just when you require strong stem cells the most, you're becoming increasingly deficient. And your muscles aren't the only part of your body affected. The same goes for all your inner organs and other tissues as well. They wear out and need to be restored or replaced, and with advancing age and diminishing amounts of stem cells, this restoration eventually ceases to take place. The fact that exercise alone can affect the behavior of your muscle stem cells is therefore definitely worth noting.
Furthermore, according to Professor Boppart:
"The fact that MSCs in muscle have the potential to release high concentrations of growth factor into the circulatory system during exercise also makes us wonder if they provide a critical link between enhanced whole-body health and participation in routine physical activity."
This seems entirely reasonable. But we already know that high-intensity interval training effectively increases your production of human growth hormone (HGH), also known as "the Fitness Hormone," which plays a vital role in your overall health, fitness and longevity. So whether your muscle stem cells are a critical link or not will not make or break the argument here. The bottom line is simple: vigorous exercise will help keep your body younger, longer.
Exercise for Optimal Longevity
If you need more proof that exercise is key for longevity, take a look at the research on telomeres.
Telomere length -- the length of the terminal caps of your chromosomes -- is considered to be a marker of aging and health. Thousands of studies have been published on telomeres. They're known to maintain genomic stability, prevent the inappropriate activation of DNA damage pathways, and regulate cellular aging. The telomeres, which are tiny units of DNA at the very end of each chromosome, shorten with time because they cannot replicate completely each time the cell divides. Hence, as you get older, your telomeres get shorter and shorter, until, eventually, DNA replication and cell division ceases completely and you die. Short telomeres are therefore a potent risk factor for a number of diseases, including:
Decreased immune response against infections Type 2 diabetes Atherosclerotic lesions Neurodegenerative diseases Testicular, splenic, intestinal atrophy DNA damage
Telomere shortening is now thought to be a major key that explains the process of aging itself, and holds the promise of not just slowing aging, but potentially reversing it. Animal studies have shown that these types of health problems can be reversed by restoring telomerase functioning—a particular enzyme that helps "rebuild" your telomeres.
It stands to reason that your lifestyle can either speed up or slow down telomere shortening, and research bears this out. Obesity, lack of exercise, psychological stress, and smoking all cause production of free radicals that can cleave telomeres and significantly speed up the telomere-shortening process. Exercise, on the other hand, has been shown to decrease telomere shortening, thereby promoting longevity.
Active People Tend to have Longer Telomeres
Recent research found that the white blood cell telomere length in women who were moderately or highly active had a 0.07 standard deviation increase. According to the authorsiii:
"Greater moderate- or vigorous-intensity activity was also associated with increased [telomere length] ... Associations remained after adjustment for body mass index ... Although associations were modest, these findings suggest that even moderate amounts of activity may be associated with longer telomeres, warranting further investigation in large prospective studies."
Exercise has also been shown to have a buffering effect, protecting your telomeres from the damaging impact of chronic psychological stress. A 2010 studyiv that included 63 healthy post-menopausal women found that:
"[V]igorous physical activity appears to protect those experiencing high stress by buffering its relationship with telomere length (TL)."
In fact, among the women who did not exercise, each unit increase in the Perceived Stress Scale was related to a 15-fold increase in the odds of having short telomeres. Those who did exercise regularly showed no correlation between telomere length and perceived stress! For more information about telomeres, Greta Blackburn's book The Immortality Edge: Realize the Secrets of Your Telomeres for a Longer, Healthier Life does nice job of expanding on this. Her book provides a great overview of this fascinating and groundbreaking realm of longevity research.
Being able to reduce telomere shortening—essentially slowing down the cellular aging process that eventually kills you—is one of the most promising anti-aging strategies we know of to date. Much of the research surrounding telomeres is focused on turning on a gene that produces telomerase. But in the meantime, high-intensity interval training appears to be the most effective all-natural approach to slow down the aging process by reducing telomere shortening. In fact, research has shown there's a direct association between reduced telomere shortening in your later years and high-intensity-type exercises.
High Intensity Interval Training—Your Best Anti-Aging Prescription!
In a study published in Mechanisms of Aging and Development two years ago, the authors' statev:
"The results of the present study provide evidence that leukocyte telomere length (LTL) is related to regular vigorous aerobic exercise and maximal aerobic exercise capacity with aging in healthy humans. LTL is not influenced by aerobic exercise status among young subjects, presumably because TL is intact (i.e., already normal) in sedentary healthy young adults. However, as LTL shortens with aging it appears that maintenance of aerobic fitness, produced by chronic strenuous exercise and reflected by higher VO2max, acts to preserve LTL.
... Our results indicate that leukocyte telomere length (LTL) is preserved in healthy older adults who perform vigorous aerobic exercise and is positively related to maximal aerobic exercise capacity. This may represent a novel molecular mechanism underlying the "anti-aging" effects of maintaining high aerobic fitness."
Remember, as mentioned earlier, anaerobic high intensity interval training also naturally increases your body's production of human growth hormone (HGH), which also plays a significant role in staving off aging.
The key to this type of anaerobic conditioning is to raise your heart rate up to your anaerobic threshold. Keep pushing at maximum effort for 20 to 30 seconds, and then allow yourself to recover for 90 seconds. Repeat this cycle for a total of eight repetitions. These types of exercises can be performed with or without equipment. So, while having access to a gym or exercise equipment will provide you with a larger variety of options, you don't require either. You can just as easily do it walking or running outdoors.
Another added boon is that it'll save you loads of time. Instead of doing an hour-long cardio workout, you'll be done in 20 minutes or so. The actual sprinting totals only four minutes!
Increasing Glutathione Levels Also Helps Reduce Telomere Shortening
Aside from vigorous exercise, another powerful strategy that shows great promise in reducing telomere shortening is to increase your glutathione levels. There are studies in progress indicating that increasing glutathione levels can provide similar results as high-intensity exercise to preserve telomere length.
Glutathione (GHS) is manufactured inside your cells from its precursor amino acids: glycine, glutamate and cystine, and is therefore not a compound you can ingest directly. Expensive glutathione supplements are available, but you can also increase your glutathione levels by making sure your diet includes foods rich in the sulfur amino acids your cells need to synthesize glutathione. Eating a high quality whey protein is the easiest and most convenient way to do this. Other food sources include animal foods and eggs.
I am so convinced of the research on slowing telomere shortening to live longer that I take our Miracle Whey protein every morning (typically after my morning exercise program) and have been doing Peak Fitness, which includes high-intensity anaerobic exercises about twice a week since April 2010.