Recent Blog Posts
Exercise
July 13, 2010
Everyone knows that exercise helps to promote weight loss. Most people believe that this is because more calories are burned when you’re active as opposed to when you’re sitting around the house. While this is certainly true, it isn’t the whole story. Here are three additional ways that exercise fires up weight loss, helping to keep you lean over the long haul.
If you’ve been keeping up with my previous posts, you’re undoubtedly aware that exercises produces an “afterburn” where metabolism remains elevated for several hours once you finish training. Fat burning following exercise is due to a phenomenon called excess post-exercise oxygen consumption (EPOC) that requires energy to be expended in order to return your body to a stable state. Research has found that EPOC is intensity dependent–the harder you train, the more calories you burn following the workout. Thus, while an activity such as walking will have a minimal afterburn, performing high-intensity interval training can result in over 100 additional calories burned, over and above what you burn during the exercise session itself. Lifting weights can have an even greater effect on EPOC. If you keep rest intervals short and really push yourself on each set, EPOC can last for over 38 hours post-exercise! Pretty cool, huh?
Exercise also facilitates weight loss by increasing resting metabolism, turning your body into a fat-burning machine. One caveat: not all exercise will help in this regard. In fact, only strength training has a positive impact on resting metabolism. Here’s why. Strength training builds muscle. Muscle is the most metabolically active tissue in the body. Although it has been proposed that each pound of muscle burns in excess of 50 calories a day, this estimate now seems to be a bit inflated. Recent research suggests that the actual amount is probably in the range of 30 to 35 daily calories. That’s still not too bad. If accurate, adding a mere 5 pounds of muscle will allow you to burn an extra 150 calories each and every day. That means you’ll burn an additional pound of fat every three weeks or so…while you’re doing nothing more than lounging around the house!
Finally, exercise can have indirect effects on weight loss by suppressing hunger. Understand that weight management follows a general rule of thumb: calories in vs. calories out determines whether you gain, lose, or maintain your weight. This is consistent with Newton’s First Law of Thermodynamics: take in fewer calories than you expend and you’ll shed the poundage. The good news is that studies show exercise has a positive effect on levels of various hormones involved in promoting satiety. Strength training, in particular, has shown to induce a feeling of fullness by reducing levels of a hormone called ghrelin. Ghrelin has been dubbed the “hunger hormone” – as ghrelin levels rise, so does the urge to eat. A recent study found that ghrelin levels fell 13 to 21% after an intense strength training bout. Other satiety-related hormones also are favorably regulated by exercising, thereby helping to prevent the temptation to binge out.
Stay Fit!
Brad
Exercise
June 20, 2010
One of the biggest debates in the fitness field over the past couple of decades revolves around whether performing a single set of an exercise is as effective as performing multiple sets. This controversy took on a new dimension back in 1998 when Carpinelli and Otto published a review paper in the journal Sports Medicine siding with the single set proponents. These authors cited a lack of evidence and theoretical physiological basis showing any added benefits to performing multiple sets. If true, this would have significant implications for those who workout. After all, performing just a single set is much more time efficient than performing multiple sets–you could basically get in a workout in 1/3 time!
Unfortunately, the overwhelming body of research does not support the position of Carpinelli and Otto. Two recent review papers by James Krieger can be considered definitive evidence of the superiority of multiple sets. Using a technique called meta-analysis (where the results of many studies are combined to form a conclusion with greater statistical power), Krieger determined that multiple sets result in greater improvements in both muscle development and strength compared to single-set protocols. And we’re not talking slight differences here. Strength gains were found to be 46% greater and muscle growth 40% greater when performing multiple sets. That’s major!
Interestingly, these results held true for both trained as well as untrained subjects. This runs against conventional wisdom. It had often been believed that multiple set superiority might be limited to those with training experience. Not so. The studies by Krieger provide proof that those who are new to training also benefit from performing multiple sets.
Now this is not to say that performing single sets has no utility. Clearly, a person can get stronger and more muscular from routines that employ just one set per exercise. But it is just as clear that if you want to maximize these parameters, multiple sets are a must. This is even more important for more advanced trainees, as the body adapts to the stresses of exercises and thus greater increases in volume are necessary to elicit additional improvements in body composition and strength. Bottom line: While single set programs may suffice if you are time pressed, at least 2 to 3 sets are required per exercise for best results.
Stay Fit!
Brad
Carpinelli RN, Otto RM. Strength training. Single versus multiple sets. Sports Med. 1998 Aug;26(2):73-84.
Krieger JW. Single vs. multiple sets of resistance exercise for muscle hypertrophy: a meta-analysis. J Strength Cond Res. 2010 Apr;24(4):1150-9.
Krieger JW. Single versus multiple sets of resistance exercise: a meta-regression. J Strength Cond Res. 2009 Sep;23(6):1890-901.
Exercise
June 15, 2010
Gym lore professes that altering the position of your legs while performing leg extensions can selectively target different aspects of the thighs. Evidence supporting this claim, however, is highly speculative.
Some studies have shown that turning your legs out (externally rotating them) increases stimulation of the vastus medialis (the teardrop-like muscle on the inside of your leg) and that turning your legs in (internally rotating them) shifts the emphasis to the vastus lateralis, the muscle located on the outer portion of your leg. If true, this would allow you to selectively target one quadriceps muscle over the other, providing a means to improve symmetry and correct strength imbalances in the quadriceps. Other studies, however, have shown no benefit to internal or external rotation of the legs during extensions, with the vastus lateralis and medialis receiving fairly equal work. When looking at the totality of research, the evidence of a beneficial effect is equivocal. At best, it would appear that the overall ability to target individual muscles of the quadriceps is minimal, with limited impact on strength and shape.
Now consider that employing the technique could come at a heavy cost. Even under ideal circumstances, the leg extension places a great deal of stress on the knees. Since loading is applied perpendicular to the long axis of the tibia, it creates tremendous shear force on the patellar region. What’s more, during performance, the quadriceps reacts to the movement by pulling the tibia forward (a phenomenon called tibial translation), causing the anterior cruciate ligament (ACL) to oppose the action. This can overstress the ACL, potentially injuring the ligament (and other soft tissue structures, as well).
Turning the legs in or out will only exacerbate these effects. Excessive internal or external rotation puts the patella in a position where it tracks in an unnatural way. Combined with effects of shear force and anterior tibial translation, stress to the knee capsule is heightened, significantly increasing the prospect of injury. This isn’t something to take lightly. An injury to the knee can set back your training efforts indefinitely, perhaps even requiring surgery and a lengthy rehabilitation stint.
Given the facts, I’d caution against any extreme rotation of the legs when performing leg extensions. The risk/reward ratio simply isn’t favorable. During performance, keep your toes straight or slightly angled out. This will allow optimal tracking of the patella and thus minimize injury potential. Your knees will thank you.
Stay Fit!
Brad
Exercise
May 4, 2010
Of all the emails I receive, the most common question asked is, “How can I reduce my (fill in the blank with a given body part).” Whether it’s the belly, thighs, butt or any other problem area, my answer is always the same: Sorry, but you can’t spot reduce!
Simply stated, there is no way to dictate what area of your body you lose fat from. It’s a physiologic impossibility. All the sit-ups in the world won’t give you a flat stomach; no amount of lower body exercises will directly diminish the size of your thighs. In reality, trying to eradicate your problem areas with targeted movements is literally an exercise in futility.
A recent study conducted by Redman et al. (2007) demonstrated the senselessness of trying to spot reduce. Thirty-five overweight subjects were placed into one of three random groups: a control group who ate their normal diet; an energy restricted group who reduced calories by 25%; or an energy restriction plus exercise group who reduced calories by 12.5% and increased energy expenditure through exercise by 12.5%. After six months, results showed that although fat depots were reduced by approximately 30% in men and 25% in women in both the calorie restricted and the calorie restricted plus exercise groups, the distribution of the fat depots were reduced equally throughout the whole body. This study used both dual energy X-ray absorptiometry (DEXA) and multi-slice computed tomograpy (CT) to evaluate fat mass, adding to the validity of results.
In order to appreciate why spot reduction doesn’t work, it is necessary to understand how fat is synthesized. When calories are consumed in abundance, your body converts the excess nutrients into fat-based compounds called triglycerides, which are then stored in cells called adipocytes. Adipocytes are pliable storehouses that either shrink or expand to accommodate fatty deposits. They are present in virtually every part of the body. There is a direct correlation between the size of adipocytes and obesity: the larger your adipocytes, the fatter you appear.
When you exercise, triglycerides are broken back down into fatty acids, which are then transported via the blood to be used in target tissues for energy. Because fatty acids must travel through the circulatory system—a time-consuming event—it is just as efficient for your body to utilize fat from one area as it is another. In other words, the proximity of fat cells to the working muscles is completely irrelevant from an energy standpoint. Since the body can’t preferentially use fat from a particular area, it simply draws from adipocytes in all regions of the body including the face, trunk and extremities.
Bottom line: When you exercise, fat will be burned globally throughout your body. Some areas will be more sensitive to fat loss than others, but over time you will lean out even the most stubborn problem areas provided you stay regimented with your exercise routine and maintain a caloric deficit.
Stay Fit!
Brad
Redman LM, Heilbronn LK, Martin CK, Alfonso A, Smith SR, Ravussin E; Pennington CALERIE Team. Effect of calorie restriction with or without exercise on body composition and fat distribution. J Clin Endocrinol Metab. 2007 Mar;92(3):865-72
Exercise
April 9, 2010
I receive thousands of emails over the course of a year, but wanted to share one I received recently. It is reprinted here unedited in its entirety:
Dear Brad,
Just a quick note to THANK YOU for putting together your 28-day Body Shapeover book. It is “THE” book that just takes out all the guesswork in resistance training, and from wasting ridiculous amounts of money on lazy personal trainers!
I have been heavy-set for as long as I can remember, but got even heavier after having my three children who are now ages 17, 11, and 10. At my highest, I was 320 lbs and that was back in 2006. Since that time, I have been one of those who went through the yo-yo diet and exercise phases going from 320 to 240 then back to 300 and down to 280 – ridiculous times. I finally found myself and decided that if I just accept the challenge as part of my everyday life, as opposed to a chore or “must do” then I would enjoy working out and eating right.
So in January I did just that – it wasn’t easy – I still failed myself many times by going days/weeks without working out and eating crap; late February was a natural turning point and I haven’t stopped since. I’m a member at my local Gold’s Gym and started doing just cardio + good eating. Last weekend, I went to Barnes and Noble to find the “right” book to guide me with my resistance training (I’ve been out of work since June 2009 and couldn’t afford a trainer; was determined that finances wouldn’t deter me). There were so many books, but many made it seem so much more complicated that what resistance training really is. So I really liked your book because of its preciseness, guidance, versatility, and facts. IT’S THE BEST $20 I’VE EVER SPENT ON MYSELF!!! I have been following the plan since Monday and my body already feels the workouts. I’ve spent on trainers before – and in my opinion were a waste of my time and money.
So long story short (sorry) – I am super excited to have found your book, and super excited in incorporating your exercises into my regimen. I started at 264 on Monday, and am at 261 today.
THANK YOU SO MUCH FOR MAKING RESISTANCE TRAINING EASY AND EXCITING!
More power to you!
Jennifer
I’m always humbled when I receive these kinds of emails. Exercise is a complex science. I pore over dozens upon dozens of research articles every week in my never-ending quest to stay on the cutting-edge of the fitness field. The difficult part is to make this information accessible to the masses and to do so in a manner that can be practically applied to optimize results. I strive to attain this feat in all my writings, including here on this blog. Knowing that I’m accomplishing my goal is ultimately what makes my life’s work worthwhile.
If you have any thoughts you like to share on my blog or books, please send them to me. I read and respond to every one of my emails individually. As I said, it means a great deal to me to know that I’m making an impact.
Stay Fit!
Brad
Exercise
April 8, 2010
I will be doing a live webinar in this coming June, 2010. The webinar will be hosted by the National Strength and Conditioning Association (NSCA). The topic is one of my favorites: Facts and Fallacies of Fitness. I’ll post additional details shortly. Hope you can attend!
Stay Fit!
Brad
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
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
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
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