This space has been utilized for the purpose of nutrition and diets, but the subjects of diet and exercise are so thoroughly entwined that I thought I would spend a few words on the effect of aerobic versus anaerobic exercise as it pertains to body fat loss. These two terms are generally used to describe strength training (anaerobic) and what most people mistakenly refer to as cardio (aerobic), such as walking, jogging, stationary bike etc., where the heart rate is kept relatively low and steady for an extended period of time. Lets define both before we delve into which would better help you achieve your weight loss goals. The following is the biochemistry (hang with me here) of these energy systems.
These two terms refer to energy systems that our bodies utilize to fuel the muscle contractions that occur during all types of exercise. The fuel is called ATP (adenosine triphosphate). The Anaerobic system may be further divided into the phosphagen system that will last 14-20 seconds and the glycolitic/lactic acid system which takes over for the next several minutes depending on the intensity of the exercise. Prolonged exercise of low intensity will eventually exceed your body’s ability to produce ATP molecules from glucose or lactic acid, resulting in fat being burned in the mitochondria in the presence of oxygen, or, aerobic activity. An exercise may be both anaerobic and aerobic. Let me explain.
I will use running as our exercise, and our healthy, injury-free exerciser has warmed up by walking for a few minutes then jogged for a couple more. Our runner takes a one minute break, then begins to sprint. The initial fuel is a substance called creatine phosphate (CP) that is available for immediate use for approximately 6-8 seconds. Your body can immediately produce more from ATP stored in the muscle to give you another 8-12 seconds of sprinting for a total of approximately 14-20 seconds of maximal intensity. At this point you will begin to slow. Your body will now switch to the other anaerobic system which is actually two distinct sytems, glycolysis and lactic acid.
Glycolysis uses available blood sugar (glucose) in the blood stream and then the storage form (glycogen) from your muscle and liver to produce a substance called pyruvic acid, which is then converted to ATP molecules to be used in the muscle. At some point this system cannot keep up with demand, due to glucose depletion and/or oxygen debt, and the pyruvic acid is converted to lactic acid and diffuses out of the muscle into the bloodstream. Later, when oxygen is again available, the lactic acid will be reconverted back to pyruvic acid to be used by the muscles to produce ATP.
If you were to continue to exercise without adequate recovery of glucose or oxygen, you will begin utilizing the aerobic system, where fatty acids enter the mitochondria and, through a series of chemical reactions, produce ATP for the exercising muscles. This only happens with very low intensity, long duration forms of exercise. If the aerobic system is burning fatty acids for its primary fuel source, then this would be the most efficient way to get leaner right? Not necessarily.
If you jog a mile on relatively flat terrain you will burn approximately 100-140 calories depending on several variables including bodyweight and composition as well as efficiency of motion and stride length. If you average 5 miles per hour, you will expend approximately 500-550 calories per hour for a 130 lb female, 650-700 for a 200 lb male. That is a very good rate of expenditure. If you perform high intensity weight training for an hour with no more than a 60 second rest interval between sets you will expend about the same amount of calories. That number rises 25%-30% if you cut the rest break to 40 seconds.
The most pronounced difference between the two forms of exercise is the effect on body composition. Strength training has the capacity to induce muscle hypertrophy, or thickening of the muscle fibers. These enlarged muscle fibers are more metabolically active, requiring additional calories to sustain them while at rest. Aerobic exercise has virtually no capacity to hypertrophy muscle mass, in some cases inducing atrophy or a loss of lean muscle mass and in turn lowering your resting metabolic rate. This difference is stark and significant!
To summarize, if you want get lean and in the process increase your body’s rate of calorie expenditure, get in the weight room and add some muscle.
I am frequently asked by clients and friends “If I want to lose weight do I have to give up drinking”? That depends on a host of variables that must be discussed. “If I cut back to a 12-pack of beer a night, will that help”? (real question from an acquaintance). It will help you pee less, but a little greater sacrifice might be necessary. Let’s breakdown the digestion of alcohol, how it interacts with protein, fat and carbs, and lastly, discuss the caloric content of different types of alcohol.Read More»
Endocrinology, the branch of physiology and medicine that researches the endocrine glands and the substances they produce, (hormones), has revealed several important discoveries over the last two decades or so. Among these were the identification of two hormones, leptin and grehlin, that have a pronounced effect on human body composition, namely, how fat or how lean one is. The health implications in an era of increasing obesity in both children and adults could well be profound.
First, let’s define what a healthy body composition is in terms of body fat percentage. That refers to what percentage of our bodyweight is fat mass. There are several methods available to get this percentage including caliper testing, bioelectrical impedance and hydrostatic weighing. These three methods all have varying ratings of accuracy and should be used as a relative gauge of body composition. The only method considered to be 100% accurate involves the burning of the cadaver, and of course, you don’t get your result back!
A consensus on what constitutes a healthy body fat percentage range is debatable, but generally speaking, a male should be under 25%, a female under 30%. Obesity is defined as over 26% for males, 31% for females. There are numerous variables that affect this percentage.
- Genetics-this broad category reflects hormonal and physiological factors that include:
- Number and location of adipose (fat) cells. You are born with a certain number, usually distributed in similar location(s) as one or both parents.
- Endocrine output and efficiency. The amount of various hormones and their circulation and utilization.
- Activity level
- Dietary intake
- External factors including environment and socio-economic status
- Adequate sleep, for most this means at least 7 hours
We can manipulate and, for the most part, control activity, sleep and diet, and to a lesser extent environment and socio-economic status. You cannot (at the time of this writing) go back and choose different parents.
Leptin and Grehlin, known collectively as the “hunger hormones”, are relatively new, with Leptin identified in 1994 and Grehlin in 1996. Leptin, produced primarily in adipose (fat) cells, suppresses hunger, while Grehlin, produced primarily in the gastrointestinal tract, stimulates appetite.
Leptin’s primary function is regulation of fat stores and is released when fat cells are at or near capacity for fat storage. Receptor sites on the hypothalamus, the part of the brain that controls energy homeostasis, signal the brain when stores are at or near capacity, and a reduction in appetite follows. Paradoxically, obese individuals have high levels of Leptin, indicating a resistance to Leptin much like Type II diabetics are insulin resistant.
Grehlin is released when the stomach is empty, stimulating the urge to eat, and ceases when the stomach is stretched. Additionally, Grehlin stimulates an increase in gastric acid secretion to prepare the digestive tract for digestion.
An interesting correlation between sleep deprivation and reduced Leptin levels/increased Grehlin levels has been observed. Some researchers speculate there may be a connection between increasing obesity levels and decreasing sleep levels over the last several decades.
Though we cannot manipulate genetics to any large degree, the variables we can control are inter-related: diet, activity and sleep. Nothing has changed in my lifetime, optimal health still requires proper nutrition, exercise and recovery.
Meal frequency is an important consideration for not just getting leaner, but for general health and well-being as well. Most nutritionists consider multiple smaller meals (4-6) an important aspect of a more effective dietary regimen than 2 or 3 larger ones, but there are several variables to consider. Let’s review these variables, then some snack suggestions will follow.Read More»
In the ever-expanding world of dietary experts and nutrition advice-givers, the debate on how much dietary carbohydrate should we consume rages on. Now, to be sure, this question must be framed more precisely. Are we talking about reducing bodyfat or optimal performance from an athletic standpoint, because the answer will vary depending upon one’s goal(s). For this writing, we will address bodyfat reduction and general health, with some ideas on how to make a potentially bland tasting food more appealing.Read More»
Over the course of the last several decades, there have been literally thousands of books and articles penned purporting to offer the latest and greatest diet for attaining that “swimsuit model” appearance that so many of our population desire. Now, to be clear, there are some really, truly, crazy diets floating around out there. Some of these will result in weight being lost, but at what price? I suppose there are those folks that are perfectly okay with some side-effects if the ultimate result is now they can fight their way into their skinny jeans. “So what?” if your skin looks a bit reptilian and you’ve not had a solid bowel movement for three straight weeks. Have you seen my butt in these jeans?!?Read More»
The relationship between the amount and quality of your sleep may be a critical component to the ultimate success you achieve in losing excess fat stores and maintaining a healthy state of leanness. Conversely, lack of sleep (in quantity and/or quality) may be a leading cause in your weight gain or inability to lose weight. Over the last few years, health researchers have confirmed what many have surmised for some time, the correlation between sleep and body composition.
The ideal amount of sleep cannot be narrowed down to a single specific amount of time, but rather a range of time, believed to be between 6.5-8.5 hours. Additionally, the “quality” of sleep is an integral part of the equation. The quality of sleep is defined by “sleep cycles”, with each cycle containing 5 stages measured by brain wave activity. Each cycle is approximately 90-110 minutes in duration.
The stages are:
(1) Drowsiness signals the change from awake to light sleep. Duration is 5-10 minutes.
(2) Sleep onset, disengagement from surroundings, body temperature begins to drop. Brain wave activity begins to slow. Duration is 45-55 minutes, the longest of the cycles.
(3) The beginning of restorative sleep and the appearance of very slow brain waves (delta waves). Blood pressure begins to drop, skeletal muscle begins to lose tension. Disorientation occurs if awakened during stage 3 and stage 4. Duration is 5-10 minutes.
(4) The deepest state in the sleep cycle. Skeletal muscle completely relaxes, very shallow breathing and lowest blood pressure readings. Coupled with stage 3, necessary for full restorative sleep. Tissue repair & Growth Hormone release occur. Immune system is strengthened. Duration is 10-20 minutes.
(5) REM (rapid eye movement) sleep. The dream state. Heart rate and blood pressure elevate, some limb movement may occur. This stage is often mistakenly referred to as the restorative stage. It is not. Depending on the nature and intensity of the dream, one may be totally relaxed, or fighting giant monster snakes! It is true that one must get to REM sleep to begin a new sleep cycle. Initial REM phase lasts 10 minutes with each successive cycle typically lasting longer.
During the sleep cycle, the hormones leptin and grehlin are regulated. These hormones control apetite, and may explain the urge to overeat in those with chronic sleep deprivation. Additionally, cortisol, the hormone that is responsible for achieving a state of alertness after sleeping, dips as night falls and slowly increases as we pass through the sleep stages. When sleep deprived, cortisol production may increase. Over-production of cortisol is associated with visceral fat, that which is stored around the organs.
Additionally, when sleep is inadequate, the odds are that you will either have a sluggish workout or do what I do, skip the session entirely. The amount of caffeine that I would require to do justice to a serious strength training session is border-line dangerous when I am sleep-deprived, so I put it off for a more energetic day.
Potential Causes of Inadequate Sleep
Some of the more common causes of sleep deprivation are:
- Too much, or hyper-sensitivity to, stimulants. The afore-mentioned caffeine is the most common offender. This will vary greatly between individuals in how much is too much.
- Too much alcohol. Alcohol is a depressant that may help with falling asleep, but has a “rebound” effect as it clears the system that may result in waking, then difficulty in returning to the sleep state. Additionally, arising to urinate does not help.
- Medications. This covers a wide range of physiologic effects, from increased frequency of urination to the stimulant effect most decongestants produce.
Scientists and health-care providers have known for ages the importance in adequate sleep. We now know this is vitally important to virtually every health aspect of achieving proper wellness, including the ability attain and maintain your ideal body weight.
Genetic modification of plants has been practiced by farmers for many centuries, crossbreeding different varieties to achieve a more robust variety, that in turn is more drought, disease, weed and pest resistant as a result. The acronym GMO stands for genetically modified organism, but is also used to define any plant that has been genetically modified. GMOs are currently one of the more controversial food related subjects, but the science is rather clear-cut on the issue.
There is currently more than 430 million acres of GMO crops globally. Though the practice of gene manipulation through crossbreeding has been utilized for over a thousand years, actual lab created varieties were first successfully produced in the early 1980s. These became available commercially to U.S. farmers in 1996, and are in widespread use today. In 2014 the periodical “Popular Science” interviewed numerous scientists pertaining to some of the more common myths that have been circulated by various interest groups, and their results were quite enlightening. Here are a few of those myths the scientists addressed.
- GMOs are too new for us to know if they are dangerous.
To date, over 1700 peer-reviewed safety studies have been published including 5 lengthy reports by the National Research Council that focused on human health and the environment. The scientific consensus is existing GMOs are no more or less risky than conventional crops.
- GMOs cause allergies, cancer, and other health problems.
Theoretically, it is possible for a new gene to express (produce) a protein that provokes an immune response. A frequently cited 2012 study from the University of Caen claimed that one of Monsanto’s corn GMOs caused tumors in lab rats. The published study was widely discredited for faulty test methods, and the publishing journal retracted it in 2013. More recently, the University of Perugia in Italy released a review of 770 studies examining the health impact of GMOs on humans and animals. They found no evidence that the foods are dangerous.
- GMOs are not necessary to feed the world’s population.
GMOs may not completely solve the world’s food adequacy problem, but the increase in population will require an increase in crop production. Pedro Sanchez, director of the Agriculture and FoodSecurityCenter at ColumbiaUniversity’s Earth Institute states “GMOs is just one more tool to make sure the world is food secure when we add 2 billion more people by 2050. It is not the only answer, and it is not essential, but it is certainly one good thing in our arsenal”.
- All research on GMOs has been funded by Big Ag.
This is simply not true. Over the past decade hundreds of independent researchers have published peer-reviewed safety studies. At least a dozen medical and scientific groups worldwide, including the World Health Organization and the American Association for the Advancement of Science, have stated that the GMOs currently approved for market are safe.
One should always question and research any new finding pertaining to health. Seek out the author’s background or a study’s funding source, and make your best judgement based on facts.
The supplement industry generates over $30 billion in product sales while contributing over $60 billion to the U.S. economy annually when including research, manufacturing, packaging, and distribution. This sector of the economy generates and supports approximately 450,000 jobs nationwide, and is one of the fastest growing industries globally.Read More»
A few years ago, I wrote a piece on gluten, the protein found in many grains, including wheat, barley and rye. Suddenly, it seemed, the whole planet was allergic or at least gluten-sensitive, and a variety of ailments were attributed to this substance. A lengthy list of maladies were the result of eating foods that contained that “old, evil gluten.” Celiac sprue, the actual disease triggered by gluten ingestion that results in damage to the villi that line the intestinal tract, is quite rare, occurring in less than 1% of the population, and is usually diagnosed at an early age, primarily during childhood. There is a strong genetic association with celiac sprue, but may occur in those with no family history of the disease. Typically, a small intestine biopsy is required to identify and diagnose. Some of the symptoms may be quite serious because the absorption of nutrients that normally occurs in the small intestines is greatly diminished, leading to various potential deficiencies including anemia.Read More»