Juvenon Health Journal – February 2014, No. 2
Sparked by an age-old quest for the most efficient exercise regime comes new research that indicates that your workout may require less time than previously thought. Swallow your too-busy-for-exercise excuses and read up on some research that supports the benefits of high intensity interval training (HIIT).
High intensity interval training is characterized by intermittent periods of work and rest and may include bouts lasting seconds to minutes. Studies have shown that sessions of high-intensity exercise can be as effective, physiologically, as longer periods of prolonged endurance exercise.
Exercise physiologists now believe that interval training (Wright and Perricelli 2008) is one of the most effective ways to exercise at a high enough intensity to significantly increase oxygen demands and ultimately boost metabolism. Again, interval training consists of short bursts of going all out followed by brief periods of recovery.
A May 2013 New York Timesarticle helps provide guidelines to the latest exercise research. The “7-minute workout” consists of 12 different exercises that emphasize different muscle groups. In the article, Chris Jordan, the director of exercise physiology at the Human Performance Institute in Orlando, Fla., explains that “those seven minutes should be, in a word, unpleasant. The upside is, after seven minutes, you’re done.”
However, it’s important to note that high intensity interval training does not have to be the type of high-impact aerobics that may cause injury.
Not surprisingly the trend has caught on like wildfire and there are online programs and smart phone apps that can keep track of the timing.
“Oh I wish I still had her metabolism,” laments a middle-aged mother, while watching her slim teenaged daughter tuck into her second helping of calorie-laden pasta.
Without cracking a single scientific journal, this woman understands all too well that her body burns calories much differently than it did three decades ago. Indeed, scientists have plenty of compelling statistics to support her notion. As early as age 25, everyone’s metabolism starts to slow down at a rate of 1 to 2 percent (or more) a year. That means that by age 60 your metabolic rate has slowed by at least 40 percent.
The good news is that there is substantial scientific research suggesting that exercise may help to “fix” a stalled metabolism. However, before we discuss this repair method, let’s get a better understanding of how the metabolic process should optimally work.
Think of a fast metabolism as the blue flame from a hot furnace that quickly and cleanly burns through fuel (calories), while a slow and inefficient metabolism smolders and produces a lot of smoke, but doesn’t burn as much fuel or get very hot.
Essentially metabolism is a collection of mitochondria. These are the spark plugs of the cells that are responsible for metabolism. The greater the activity of the cell, the more mitochondria it has. For instance, the energy needs of skin cells are the lowest while the heart has as many as 5,000 mitochondria per cell. Regardless of their location, when these little dynamos aren’t operating cleanly and efficiently, it impedes your metabolism, resulting in energy slow down throughout your body. This in turn, puts you at risk for a host of illnesses and diseases of aging.
How Exercise Can Repair an Inefficient Metabolism
It probably doesn’t come as a surprise that exercise helps your metabolism, but you may be interested to know why.
Aside from burning calories from the food we eat on a daily basis, exercise normalizes our metabolism by establishing balance. Our bodies seek an economy of scale in which certain aspects of physiological strength, capacity, endurance and speed are forfeited when they aren’t regularly called upon. In other words: ”use it or lose it.“ Similar to a motion-activated light, our physiological and metabolic economy turns off when not in use and only turns on with added function if called upon later.
The mitochondrion is the arbiter of all cellular energy and fuel the sum of catabolic (breakdown) and anabolic (building) functions in our cells, which we collectively refer to as metabolism. Ultimately, our mitochondrial population and competence are subject to the same ”use it or lose it“ credo as every other physiological system in our bodies. Left untrained, the mitochondria will reduce in population, size and efficiency.
A vast body of research reveals that exercise dramatically increases the population of mitochondria in our cells, especially in the heart, nervous system and skeletal muscles. Perhaps as important, exercise increases the energy output of mitochondria, which translates into efficient fat burning and fewer damaging free radicals. Lastly, exercise has been found to stimulate the turnover of mitochondria, constantly building new and more efficient mitochondria.
A study published in the British Journal of Sports Medicine showed that regular aerobic exercise could decrease biological age by 10 years or more. Another study published in the Journal of Applied Physiology explored the topic further and determined that one of the ways aerobic exercise decreases biological age is by improving mitochondrial function aka metabolism.
In a nutshell, activity level correlates with improved mitochondrial function and in turn metabolism. The more effort a person puts into exercise, the greater are the metabolism changes. Exercise has been found to increase the population of mitochondria in your cells and repair their sluggish energy output. Importantly, there is also an increase of turnover of mitochondria, the constant building of new and more efficient mitochondria.
Exercise Your Legs – Benefit Your Brain
As discussed earlier, scientists now believe that exercise stimulates the growth of new healthy mitochondria, and in turn a more efficient metabolism, over time. This news has far-reaching implications and it’s not just your body that benefits.
Recent technological advances such as genetic microarray chips and sophisticated microscopes have allowed researchers to identify the molecules in the body that support growth of mitochondria and youthfulness. They are thus able to identify many of the specific cellular effects of exercise – especially in large muscles.
Scientists now believe the primary molecule in the body that stimulates growth of mitochondria – PGC-1alpha – is activated by exercise. This ”exercise molecule“ activates the growth of new mitochondria; therefore even older people may enjoy certain aspects of youth, such as strong muscles, endurance and brainpower.
When you exercise your legs, for example, PGC-1 alpha is stimulated all over your body. That means that by exercising one part of your body, you can build up the mitochondria all over your body; for example, in the brain. Even older people can have youthfulness – strong muscles, endurance, brains, memory, and energy. People who exercise often look younger, too.
To be sure, age and genetics both play into how efficiently one’s individual metabolism works. Still, a healthy metabolism’s trickiest adversary just may be our modern lifestyles. Sadly, our lives feature little or no exercise. Not exactly the best route to a humming metabolism.
Fortunately, there are some simple, scientifically proven changes that you can make to your lifestyle. If you don’t exercise already, there is no time like the present to start. To up your metabolic game even more, consider interval training, which has been found to be as effective as longer workouts.
In the coming months, the Juvenon Health Journal will explore other methods that can help jumpstart a slow metabolic process. Remember, a slow metabolism is not terminal, but it can become permanent if left unchecked. If you are new to exercise, discuss your get-moving plan first with a trusted healthcare professional.