Recent Blog Posts
Nutrition
April 7, 2010
If you’ve followed my teachings over the years, you’ll know that I believe in taking an individualized approach to nutrition. Simply stated, there is no one diet that is best for everybody. This view is not simply a personal opinion based on anecdotal experience; it’s backed up by a significant amount of research. Studies consistently show that people respond differently to different macronutrient profiles. Here’s an example. A study by Tay and colleagues reported that LDL (i.e. the “bad” cholesterol) levels remained unchanged after subjects consumed a low carb diet over 24 weeks. However, a closer look at the individual responses of participants in the study paints a vastly different picture. Almost 60% of low carb dieters actually showed a reduction in LDL while 24% showed an increase of at least 10%! Such widespread discrepancies can only be attributed to differences in genotype (i.e. the genetic makeup of an individual).
Now, recent research reveals that we may be closer to having an effective tool in customizing diets based on individual response. Data presented at the American Heart Association’s Nutrition, Physical Activity and Metabolism Conference showed that examining the activity of genes involved in fat metabolism can help predict what type of diet is best for a particular person. The researchers used a cheek swab to obtain genetic info on three genes–fatty acid binding protein 2, peroxisome proliferator- activated receptor gamma, and beta 2 adrenergic receptor–then sought to determine response to various diets (i.e. high-carb, low-carb, etc). The verdict? The genes studied had an extremely high correlation as to what diet worked best for the individuals, with those assigned to a the proper diet for their genotype losing up to three times as much weight after a year compared to those who were not assigned to a genotype-appropriate diet.
Now before we get too caught up in numbers, a few things to keep in mind. First, this was just an abstract and the data have not yet been published in a peer reviewed publication. Hence, results need to be interpreted with caution. Second, several of the researchers have a financial interest in the kit used to collect and interpret the info, which has the potential to introduce bias into results. That said, the research was carried out at a very prestigious university (Stanford) and the theoretical basis behind the approach is certainly sound. It will be interesting to see how this plays out, but it represents a potentially exciting development in nutritional science that has important future implications.
In the meantime, the best advice is to experiment with different macronutrient profiles and see how your body responds. A little trial-and-error goes a long way to optimizing a dietary approach that works best for you.
Stay Fit!
Brad
Tay J, Brinkworth GD, Noakes M, Keogh J, Clifton PM. (2008). Metabolic effects of weight loss on a very-low-carbohydrate diet compared with an isocaloric high-carbohydrate diet in abdominally obese subjects. J Am Coll Cardiol. 1;51(1):59-67.
Exercise
April 3, 2010
The abstract of my recent peer-reviewed journal publication titled Squatting Kinematics and Kinetics and Their Application to Exercise Performance is now available for viewing in publish-ahead-of-print format on both Pubmed and the Journal of Strength and Conditioning Research website. The article assesses squatting biomechanics and then discusses their application to exercise training. I will post more on the subject in the future.
Stay Fit!
Brad
Nutrition
April 2, 2010
I’ve discussed the myriad benefits of consuming adequate amounts of omega-3 fatty acids numerous times in this blog. As I’ve detailed previously, the benefits of omega-3s extend to virtually every organ system, and include facilitating loss of body fat. There are few nutritional topics that have as much research-based support.
A recent study in the Journal of the American Medical Association (JAMA) sheds some light on how omega-3s may protect against aging. The study looked at the effect of omega-3 intake on telomeres, which are repeat DNA sequences that form a “protective cap” at the ends of chromosomes. It has been previously shown that telomere length degrades over time, exposing cells to early death. This has led researchers to conclude that telomere length may be a marker of health and well being, with shorter telomere lengths associated with premature aging and the onset of cardiovascular disease.
In the JAMA study, researchers examined the relationship between blood levels of omega-3 fatty acids and telomere length in leukocytes (i.e. white blood cells) over a period of five years. Results showed that those who had the lowest levels of omega-3s (as determined by DHA+EPA) showed the greatest telomere shortening while those in the top quartile had the least degree of shortening. This inverse relationship between omega-3s and telomere length lends support to the anti-aging benefits of fish oil consumption. It is yet one more in a long line of studies showing just how important it is to get adequate omega-3s in your diet.
Stay Fit!
Brad
Farzaneh-Far R, Lin J, Epel ES, Harris WS, Blackburn EH, Whooley MA. (2010). Association of marine omega-3 fatty acid levels with telomeric aging in patients with coronary heart disease. JAMA, 20;303(3):250-7.
Exercise
March 30, 2010
I routinely see people in the gym performing calf raises with their toes pointed every which way. They’ll turn their toes inward (pigeon-style), then forward, then outward…and pretty much every direction in between. All of this effort is undertaken in the mistaken belief that changing toe position allows you to work different areas of the calf muscle. Unfortunately this is not the case. Here’s why:
In order to effectively alter the stimulation a muscle receives, you need to do one of two things: 1) increase the amount of stretch on the muscle or 2) place the fibers in a position so that they more directly oppose gravity or contract in line with fibers. Turning the feet in or out accomplishes neither of these objectives. These movements (called internal and external rotation) are achieved by rotating at the hip. The problem here is that the calves, of course, don’t cross the hip joint! They are affected only by movements that take place at the ankle and (in the case of the gastrocnemius) the knee joints. Hence, there’s no physiologic way foot position can be of benefit in enhancing calf development.
What’s more, performing weighted calf movements with the feet splayed too far in or out can place undue stress on the knee joint. The knees simply aren’t meant to track in this fashion, and doing so can heighten the potential for soft-tissue injury.
So the question really becomes: Is there any way you can exert stimulation to different parts of calf muscles? The answer: To a limited degree. The gastrocnemius muscle has two separates “heads”: the medial head (which resides on the inside of the lower leg) and the lateral head (which resides on the outside of the lower leg). By rolling your foot onto the big toe (called inversion), you place the fibers of the medial head in a position to more directly oppose gravity, thereby increasing stress to this part of the muscle. Contrarily, by rolling your foot onto the little toe (called eversion), the fibers of the lateral head more directly oppose gravity, thus increasing their force production.
Now understand that this doesn’t mean you are isolating the respective heads. Far from it. Both heads will receive significant work during the exercise. If anything, the effect will be slight, with the target head being stimulated slightly more than the other.
Moreover, the soleus muscle (which lies deep underneath the gastroc), will not be affected by inversion or eversion. You can, however, target the soleus vis-à-vis the gastroc. Since the soleus only crosses the ankle joint and not the knee, it remains highly active when performing bent knee calf raises while the gastroc, which crosses both the ankle and knee, does not. Thus, exercises such as seated calf raises will focus more on the soleus whereas straight-legged movements (i.e. standing calf raises, donkey calf raises, etc), involve both the gastroc and the soleus.
Stay Fit!
Brad
Supplementation
March 15, 2010
L-Carnitine has been a popular supplement in bodybuilding and weight loss circles for many years, and it has recently seen renewed interest from its inclusion in the many “energy drinks” on the market. That begs the question: are there any benefits to carnitine supplementation? To answer this question, let’s first start with a little physiology on the substance…
Carnitine is synthesized in the liver and kidneys from the essential amino acids lysine and methionine. It also can be obtained intact from whole foods such as avocados, red meat, and various dairy products. The primary function of carnitine is to transfer fatty acids across the mitochondrial membrane so they can be oxidized to produce energy. Thus, it is integrally involved in the fat burning process, as well as helping to enhance energy levels and reduce muscular fatigue.
From a hypothetical perspective, carnitine supplementation makes sense on the surface. First, because of its role in facilitating transport of fatty acids into the mitochondria (the body’s “cellular furnace”), an elevated level of carnitine would seem to permit a greater amount of fat to be burned by the body. In addition to accelerating weight loss, this would also help to spare muscle glycogen, thereby improving exercise performance. Moreover, since carnitine plays a role in buffering lactic acid, supplementing could theoretically prolong your ability to work out at intense levels. And carnitine has various cardiovascular benefits, including the reduction of blood cholesterol and lipids. All things considered, supplementation might sound like a good idea, right?
Unfortunately, theory doesn’t transfer into practice here. The vast majority of studies have shown little or no benefit of carnitine supplementation in healthy, well-nourished individuals. There appears to be a critical level for carnitine build up, above which it provides no additional effect. While supplementation does increase blood levels of carnitine, there is not a corresponding increase in transport of fats into the mitochondria, and thus fat burning capacity is not enhanced. Provided you take in sufficient dietary protein (equating to approximately one gram per pound of body weight), the overwhelming likelihood is that you will synthesize all the carnitine your body needs. And given that carnitine is quite expensive, supplementation just doesn’t provide a good cost/benefit.
The only instance where supplementation may be beneficial is if, by chance, you happen to have a carnitine deficiency. Those most at risk for being deficient include vegans, vegetarians, breast-feeding women, and individuals on very low calorie diets. Should you fall into one of these categories, it’s possible that carnitine can be of value. Standard dosage is to take between two and four grams of carnitine approximately one hour before exercise. Again, more is not better—once you reach the saturation point, any additional intake will be superfluous. And assuming you are not deficient (as is the case with the vast majority of the public), save your money.
Stay Fit!
Brad
Nutrition
March 2, 2010
I generally don’t get political in this blog–after all, my focus is on the science of fitness, not the world of politics. However, a recent issue here in New York has motivated me to take up a cause. Namely, New York governor David Patterson has proposed a tax on soda and other sugary beverages. The tax would encompass soft drinks, energy drinks, sports beverages, and various juices and iced teas; sugar-free diet soft drinks would not be affected. It is estimated that such a tax would bring in about $1 billion over the course of a fiscal year, enough to make a significant dent in New York State’s $8.2 billion budget deficit. My only question: what took so long?
Predictably, beverage makers are up in arms over the bill. The American Beverage Association is lobbying hard to rally opposition against it. They have created an organization called American’s Against Food Taxes and set up the No Beverage Tax website where readers are encouraged to sign a petition against the governor’s proposal. They profess that tax against soda is discriminatory. They imply it is Un-American, harmful to the poor consumer who is overburdened by the recession. Before any tears well up, let’s get real here. We’re talking about making people pay a few cents more for something they shouldn’t be drinking in the first place. Here’s a simple solution for those who feel this causes financial hardship: switch to tap water–it’s free and has no calories!
Make no mistake, sweetened beverages, particularly sodas, are a major threat to public health. These beverages have no nutrient density whatsoever. Zilch! They epitomize the term “empty calories.” Worse, they are digested very quickly into your blood stream, and therefore don’t satisfy hunger—a fact that can lead to overeating. What’s more, they elicit a rapid spike in blood sugar levels, which in itself can lead to excess fat storage as well as increasing sugar cravings. And on top of everything, they’re bad for your teeth, too!
In a recent review of research appearing in the New England Journal of Medicine, Brownell and Frieden (1) reported that consumption of sugary beverages is associated with increases in body weight, poor dietary habits, and an elevated risk of obesity and diabetes. Conversely, a reduced consumption of these beverages has a positive effect on health and wellness. But that’s not the worst of it…
Soft drinks companies focus a great deal of their marketing efforts on children and adolescents, so much so that sugared beverages now comprise 10 to 15% of the calories they consume. It is estimated that each additional glass a child drinks increases his/her likelihood of becoming obese by approximately 60%. Given the epidemic of childhood obesity and its ramifications (approximately one-third of all children in New York State are classified as overweight or obese), this is something that needs to be addressed. Soon!
The real question, then, is whether a soda tax would have any impact on consumption? Evidence suggests it would. Research published in the American Journal of Public Health shows that taxes on cigarettes have substantially curbed the rate of smoking in America (2). What’s more, larger tax increases were associated with larger smoking declines, with the greatest effect seen in youth, minorities, and low-income smokers. This bodes well for the effectiveness of a tax on sugary beverages.
In their article, Brownell and Frieden estimate that for every 10% increase in price, soda consumption decreases by 7.8%. They quote an industry trade publication report that shows even greater price sensitivity: a 12% increase in the price of Coca-Cola resulted in a 14.6% drop in sales. These statistics provide powerful support to the belief that a soda tax would decrease consumption of sugary beverages. If so, this would reduce caloric intake, leading to better weight management for millions of Americans.
An essential aspect of any soda tax is that revenues must go toward offsetting health care costs (the money collected from the proposed tax in New York would be targeted for an existing pool that funds the state’s health expenses). The medical expenses associated with overweight and obesity are staggering. Taxpayers assume the majority of these costs through Medicare and Medicaid. This clearly is unjust. Why should those who watch their diet and maintain their health pay for those who don’t? If a person wishes to consume sugary beverages, that is certainly his right. But he then should be responsible for bearing the costs associated with his decision, not the taxpayers.
Bottom line is that a tax on sodas and other sugary beverages is an idea whose time has come. It will help to make us healthier as a nation, and transfer some of the economic burden of skyrocketing medical costs to those who don’t assume responsibility for their own health. Perhaps the success of such a tax in New York will motivate congress to pass a national tax on sodas and sweetened beverages. And perhaps then, despite the protests from special interest groups, we’ll have a healthier nation because of it.
Stay Fit!
Brad
1) Brownell KD, Frieden TR. Ounces of prevention–the public policy case for taxes on sugared beverages. N Engl J Med. 2009 Apr 30;360(18):1805-8.
2) Peterson DE, Zeger SL, Remington PL, Anderson HA. The effect of state cigarette tax increases on cigarette sales, 1955 to 1988. Am J Public Health. 1992 Jan;82(1):94-6.
Personal Appearances, Training Seminars
February 25, 2010
Wanted to let everyone know I’ll be conducting a seminar at the upcoming NSCA Personal Trainer’s Conference. The conference is taking place at Bally’s Casino in Las Vegas on March 7th and 8th, 2010. The topic of my seminar is “Maternal Fitness: Safe and Effective Strategies for Training the Pregnant and Postpartum Client.” Hope to see you there!
Stay Fit!
Brad
Exercise, Home Workout
February 19, 2010
The current issue of More Magazine includes an excerpt from my book, Women’s Home Workout Bible. The excerpt details my “Ten Commandments of Fitness” and can be found at the following link: How to Work Out Smarter. These are tried and true principles that are essential for optimizing exercise results. While some of the commandments may seem obvious, many people unfortunately neglect to follow through and regiment them into their workouts. Hope you enjoy the excerpt!
Stay Fit!
Brad
Exercise
February 10, 2010
I recently teamed with Heartbeat Radio 1410, a popular radio station out of central Florida, to help with a weight loss challenge they are sponsoring. Specifically, the station chose 6 contestants to go through a real-life “Biggest Loser” challenge. The goal is to see who can lose the most weight without being confined in an artificial environment. For the exercise component, contestants will be following the programs outlined in my book, Women’s Home Workout Bible. The contest started at the beginning of the year and is now well into its second month. I look forward to posting the final results of the contestants and reporting on their success. Good luck to all!
Stay Fit!
Brad
Ab Training
February 7, 2010
Hands down, no other body part gets more attention than the abs. It’s not even close. Unfortunately, there are more myths associated with the best way to trim and tone midsection than any other body part. Falling prey to these myths not only diminishes results, but you also may increase the potential for an injury.
So how do you go about deciphering ab training fact from fiction? Read on…
MYTH #1: Training the abs will give you a flat stomach.
Contrary to popular belief, you cant spot reduce fat. It’s a physiologic impossibility. When you exercise, fat is utilized (i.e. burned) from all areas of the body; you can perform crunches until the cows come home but it will have virtually no effect on losing those love handles or blasting that beer belly. What’s more, the calories expended during ab exercises are very low. There are far better exercises to expedite fat loss than crunches and side bends, particularly those that work multiple muscle groups such as squats, presses, and rows. Now training your abs will develop the underlying muscle, which is essential if you want that coveted “six pack.” But if there is a layer of fat obscuring your muscles, no one will ever see what you’ve worked so hard to develop.
MYTH #2: The lower and upper abs are separate from one another.
The abs are one long sheath of muscle–not two separate entities. Any ab exercise you do is going to involve both the lower and upper abdominal areas. However, studies show you can shift the emphasis more toward the lower or upper regions by performing specific exercises. Specifically, exercises that bring the chest toward the pelvis (crunch-type exercises) target the upper region of the abs, while exercises that bring the pelvis toward the chest (reverse curls) target the lower abdominal region.
MYTH #3: You should perform ab exercises every day for best results.
It has been taken as gospel that the abs are somehow different from other muscles and respond best to daily training. Nonsense, at least if getting a six-pack is your goal. You wouldn’t think of training the biceps or the quadriceps every day, would you? Well, the abs have the almost the same percentage of “fast twitch” to “slow twitch” muscles as the biceps and the quads. This means they are designed just as much for strength as for endurance. Realize that your muscles develop during rest. When you train, you’re actually breaking down muscle tissue. Short change results and you shortchange the recuperative process, thereby impairing results. Approximately 48 hours rest is needed between training sessions for a given muscle group–and that includes the abs.
MYTH #4: During the crunch, you should place your hands behind your head for support.
More times then not, people are taught to support their head with their hands when doing crunches. Bad idea. You see, when you clasp your hands behind your head there is a reflexive tendency to pull on the neck muscles. This greatly increases the risk for straining your neck muscles, especially towards the end of a set when you begin to fatigue and are struggling to perform those last few reps. I cringe watching some people yank their heads up as they crunch; they’re an injury waiting to happen. Ouch! The best advice is to place your hands behind your chest or put your fists at your ears. Your neck will thank you. For more detailed info on this myth, see my post Do Crunches Lead to Neck Pain?.
So there you go. Heed these truisms about ab training and you’re well on your way to a better workout…and a firmer midsection!
Stay Fit!
Brad
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