The Science of Amazing Abs

Overview

Carving out a great six-pack isn’t an easy feat—which is too bad, since virtually every person I’ve ever met wants a defined set of abs. 

But too many people view six-packs as a kind of fitness status symbol, reserved for the genetic elite or those who spend more time in the gym than they do in their own home. And that’s simply not the case. 

Yes, your genetics and diet influence just how much muscle definition you have around your midsection. But the good news is that everyone has abs—regardless of how well you can see them. And that means that everyone can build better abs. 

You might have to relearn a few things, but by incorporating the principles below and trying some new exercises, you can build stronger, better abs than ever before.

Your Abs Have More Than One Purpose

Ever wondered why sit-ups became such a popular exercise? It’s because most anatomy books state that the purpose of your abdominal muscles is to flex your spine. As a result, people think that by creating a “crunch” type movement, you’ll build your abs the way nature intended. 

Unfortunately, most anatomy books are “at least 35 years out of date,” according to Mark Comerford, a researcher, physical therapist and founding director of Kinetic Control, a consulting agency that assists physiotherapists. He says that, while your abs do flex your spine, that’s just a small part of their duty. Your abdominal muscles also…

* Create movement: Let’s say you’re standing upright, and then you bend forward at your waist as fast as you can, as if you’re a boxer ducking a punch. When you do so, you’ll feel your abs activate; since you’re moving faster than the speed of gravity. Your abs will kick in to propel your torso downward. 

* Counterbalance movement: Ok, now pretend that you’re standing upright again, this time with your hands on your belly. If you were to start leaning backwards, you’ll again feel your abs activate, but this time in a different way. Your abs are doing the opposite of what anatomy books tell you. Rather than flexing your spine, those muscles are fighting the extension of your spine to keep you from falling over.

* Resist movement: All right, last example. You’re again standing upright, but with your arms reaching straight out in front of you at shoulder-level, with your hands locked together. Let’s say a friend tried to push your arms to one side, but you didn’t want to move. How would you resist their efforts? Your abs. Your core would activate to keep your arms pointing straight ahead. 

It’s important to do exercises that will work your abs in all of these different ways to protect your body from injury and reveal the lean body you desire.

Crunches Aren't the Enemy

Crunches fell out of fashion in recent years, as fitness experts and rehab professionals began speaking out against the exercise. Most cited the work of Stuart McGill, Ph.D., a respected spine researcher who found indications that doing too many crunches can cause serious damage your back. His theory: Because they require you to flex and bend your spine, performing these exercises often could cause a person’s spinal discs to push out too far, which could result in a herniated disc.

But the truth is that claims about crunches are highly debated. Carl DeRosa, Ph.D., the author of Mechanical Low Back Pain & Mechanical Neck Pain, says that your body position isn’t responsible for putting pressure on your discs – it’s how tightly you’re squeezing (or compressing) your muscles that has the biggest impact. Other experts like spinal researcher Michael Adams, Ph.D, say that a person’s discs can actually strengthen (like your muscles) and potentially become more resilient to injury as a result of doing abs exercises like crunches properly.

The bottom line: If you have a disc-related injury, crunches might not be the best exercise for you. But for healthy athletes, a few sets (not hundreds of reps) of well-performed crunches can help activate your abs. Performing crunches on a Swiss Ball or BOSU Trainer is exercise safer than floor crunches because they offer more support. Added bonus: Since you’re on a round surface, you also have a greater range of motion.

1. Weighted Crunches on a Ball or BOSU - Position a BOSU ball on the floor with the dome side up. Lie face-up with your lower back supported on top of the dome, with your feet flat on the floor and your knees bent about 90 degrees. Hold a weight plate (or dumbbell) in front of your chest. Raise your head and shoulders and “crunch” your rib cage toward your pelvis. Hold, and then return to the starting position. Perform 2-4 sets of 6-12 reps.

Full-Body Exercises Help Build Six-Pack Abs

Almost every movement you do works your abs in some capacity—especially if you’re standing. Press a weight overhead, your abs engage. Stand on one leg, your abs are working. Struggle during a tough exercise and “cheat” a little on your form—yep, you’ll probably feel your abs coming to the rescue. 

These non-abs specific movements hit your midsection indirectly by working your “core” muscles, which are different from your abs. (Your core encompasses your entire torso, including your chest, glutes, back, and even neck muscles.) The following six movements work your core and help your abs “pop,” too.

2. Push-Ups: Everyone knows that planks are killer abs exercises. Push-ups are essentially planks crossed with a bench press, so you can strengthen your six-pack and build your chest. Start in the push-up position, with your arms slightly out in front of you and your elbows near the side of your body. Keeping your back straight and abs tight, lower your body until it almost touches the floor. Pause, then push yourself back up into the starting position.

3. One-Arm Push-Ups: This exercise is the king of upper-body pushing exercises, hitting every muscle that regular pushups hit while placing extra emphasis on your abs and obliques. Start in the pushup position but put one hand behind your back. Your other arm will be slightly out in front of you, with your elbow near the side of your body. Keep your legs wide (the wider they are, the easier the exercise). Lower your body down until your torso almost touches the floor. Pause, then push yourself up to the starting position. 

4. Standing One-Arm Cable Press: If one-arm pushups are too advanced for you, standing single-arm cable presses are the next best thing. Like the one-arm push-ups, the exercise strengthens your upper body, abs and obliques. Holding a cable in one hand, step out so that one foot is in front of you and the other leg is bent behind you. Lean forward slightly, pick your back heel off the ground, and tuck your elbow in. Drive the cable in your hand forward, pressing with your shoulder. Return quickly to the starting position and repeat.

5. Cable Chops: Stand with your feet shoulder-width apart and your abs braced. Grab a cable in one hand and pull it across your body. Then turn your shoulders and hips, as if you are swinging a bat. You have three options for the motion: high to low, low to high, or you can press horizontally, from the shoulder level. For best results, mix them up.

6. Offset Dumbbell Lunges: These lunges are a great way to work your obliques. Stand up straight with your feet shoulder-width apart and grab a heavy dumbbell in one hand. Take a step forward with one leg and lower your body until your knee is bent at a 90 degree angle. Then step forward with your other leg to return to the starting position. Take a step forward with the opposite foot and repeat the movement. Continue this pattern as you walk across the floor.

7. Tight Rotations: This body-weight movement is a relatively new exercise, but just as effective as the classics. Stand up straight with your feet shoulder-width apart with your arms straight out in front of you and hands locked together. Rotate your arms and torso as quickly as you can from left to right, keeping the movement between your feet – your shoulders shouldn’t extend past your left or right foot. Move your hips with your shoulders.

But You Still Need Ab-Specific Training

While nearly every exercise works your abdominal muscles in some way, the benefits of these movements are limited. Most only test the stability of your abs. They don’t develop other aspects of ab strength, like the ability to initiate movement. 

That’s why doing targeted abs movements is so important. Abs-specfic exercises allow you to strengthen your midsection completely, helping you build an impressive six-pack that’s built to move. And perhaps the best way to strengthen your abs is to do Swiss-Ball Pike Rollouts. A 2010 study in the Journal of Orthopaedic & Sports Physical Therapy found that both the Ball Pike and Ball roll Out exercises were the most effective way hit your upper abs, lower abs, and obliques all at once.

8. Swiss-Ball Pike Rollouts: Start in a pushup position with your hands on the floor and shins resting on top of a Swiss Ball. Your hands should be shoulder width apart, with your back kept straight. To start the exercise, tighten your core muscles and pull your legs in towards your arms, lifting your hips in the air. Pause at the top of the rep and hold for 1-2 seconds. Then lower yourself back down to the starting position, sliding your legs back over the ball until your arms are extended out in front of you. Remember to keep your abs braced and your back straight throughout the movement. Perform 2-4 sets of 6-12 reps.

By : NICK TUMMINELLO 

http://www.livestrong.com/article/556757-the-science-of-amazing-abs/

All Diets Fail. Why Bother?

From the same newspaper (and author, Gina Kolata) who told you exercise has no impact on bone health comes a new claim: obesity is the result of environment and genetics, your personal choices don’t matter, and the only effective treatment for extreme obesity is bariatric surgery.

 

The New York Times is hardly alone. The last few years have seen a flood of videos and articles suggesting that body weight is largely or entirely out of your control. These come packaged with the message to accept everyone whatever their weight, avoid disordered eating, and fight discrimination. Although the aims are noble, the claims behind them aren’t, and the evidence simply isn’t on their side. 

 

All Diet's Fail, so why even bother?

As Ms. Kolata and others are quick to point out, most diets fail. 97% of obese people in one survey claimed they had attempted to diet, often multiple times, and failed. This is consistent with most clinical studies which show that weight loss is difficult, and keeping the weight off is even harder. 

 

It’s a stretch, however, to go from “most people fail” to “you have no control, just give up.” Let’s compare dieting to quitting tobacco. Successful quitters take an average of 8-14 attempts before they manage to quit for one whole year. However, if you count those who have not yet succeeded, the best estimate is that it takes a heavy smoker an average of 30 attempts or more to quit.¹

 

It would be deeply irresponsible to tell someone “nobody succeeds at quitting smoking, so let’s just focus on being healthy at a pack a day.” So why is it acceptable with obesity?

We know it can be done. I am awed by stories like that of Leah Lutz who, with the help of her coach and community, went from 275 pounds to being a national champion Master’s powerlifter in the 72kg (158lb) weight class in less than five years. On a larger scale, the National Weight Control Registry tracks the progress and habits of over 10,000 people who have lost significant weight and managed to keep it off for over a year, and there are undoubtedly tens of thousands more success stories in the US alone. 

 

All change is hard, and obesity, especially extreme obesity, is complex. It comes wrapped up with feelings of comfort, identity, community norms, habits, self-belief, and ambivalence. On top of that, there is a vast wealth of misinformation and well-marketed diet strategies seemingly designed to create short-term success and rebound weight gain. That doesn’t mean you’re doomed to fail. 

 

It's Not You, It's Your Environment

The New York Times article concisely captures this sentiment and reflects the views of many on this issue: 

 

"Researchers say obesity, which affects one-third of Americans, is caused by interactions between the environment and genetics and had little to do with sloth or gluttony."

The problems with this statement are myriad. The first is the idea that this is the consensus of the scientific community. It’s not. This is the Center for Disease Control’s statement on the causes for obesity: 

"Obesity results from a combination of causes and contributing factors, including individual factors such as behaviour and genetics. Behaviours can include dietary patterns, physical activity, inactivity, medication use, and other exposures. Additional contributing factors inner society include the food and physical activity environment, education and skills, and food marketing and promotion."

 

It’s clear that the CDC sees the importance of personal behaviors in maintaining a healthy weight, but the point at issue here is beyond that. “Lifestyle change doesn’t work” advocates paint us as passive and helpless, battered by our environments like trees in a hurricane. Our environments may be powerful, but they are not static, nor are they entirely outside of our control. 

 

If your “food environment” isn’t great, you can still make smart choices between the available options, including the option to eat less total food (say, a handful of potato chips rather than a whole bag). If a Vietnam POW can train to do over 1000 pushups while recovering from torture, your “physical activity environment” is sufficient to get in a workout. If you’re reading this article, the education is available through the internet. Skill development is a process you choose, and there is nothing so compelling about any food marketing that you have to buy what it’s selling.

 

If the environment alone were responsible for our weight, you would expect that correcting the environment would fix the problem. The evidence suggests otherwise. Several studies have shown that placing full-service supermarkets in “food deserts” has little if any effect on BMI or fruit and vegetable consumption. Nutritional labeling may better inform the consumer, but they rarely change the behaviors of those who are not already eating well. Interestingly enough, done incorrectly, they can even backfire, encouraging buyers to make worse choices.

 

I will agree with Ms. Kolata on one point: the problem isn’t sloth or gluttony. Losing a lot of weight can be very difficult mentally, emotionally, and physically. The environment can make an already difficult change even harder. And that’s the real issue here.

 

For all their good intentions, the naysayers are part of the problem. By shouting from the rooftops that dieters are doomed to fail, they become part of that toxic change environment. They enable friends and family to sabotage their loved one’s efforts and engender a sense of hopelessness. They’re the enemies of healthy change.

It's Not You, It's Your Genes

To be fair, their argument is not that simple. The NYT article states that it’s the interaction of our environment and our genes that makes obesity inevitable in some people, not the environment alone. The argument usually goes that we have evolved to seek salts, sugars, and fats, and modern designer foods (specifically crafted to taste salty, sweet, and fatty) interact with our genes to trigger addictive behaviors. On top of that, modern labor-saving devices and retail work mean we don’t have to move a lot to stay alive.

 

It makes sense that our genes haven’t kept up, and in this environment, of course we’re fat. Unfortunately, not everything that makes sense is correct. From the Harvard School of Public Health:

 

"What's increasingly clear from these early findings is that genetic factors identified so far make only a small contribution to obesity risk - and that our genes are not our destiny: Many people who carry, these so-called "Obesity Genes" do not become overweight and unhealthy lifestyles can counteract these genetic effects."

This shouldn’t really surprise anyone. A general “gene” answer to the problem is weak.How are our parents and grandparents less obese than we are despite living in the same environment? How do success stories exist if their genes and environment haven’t changed? Can genes overcome the basic laws of physics (calories in/calories out)? 

 

There is some evidence that certain genes may make it more likely that one person may become obese than another given the same environment and habits, but they are certainly not our destiny.

 

Obesity Isn't That Bad, After All...

Some will take a completely different approach. Instead of arguing that obesity is dangerous but inevitable, they will argue that obesity isn’t really a health risk at all. The argument usually goes that it’s activity level, not body weight, that matters for health. People who are destined to be obese just need to focus on being active and happy and health will naturally come with it. 

 

Before I continue, understand that this argument actually has a lot of truth to it. I’m looking to put it in context and not dismiss it, so I’ll start with what’s right about it. 

 

Our definitions of ‘overweight’ and ‘obese’ are an issue to begin with. One of the largest reviews to date found that those who were overweight or had mild obesity (BMI of 25-35) actually had slightly lower overall mortality than those of normal weight. Although there is always the possibility of GIGO (garbage in, garbage out) skewing the data, it’s safe to say that being ‘overweight’ is not an automatic death sentence and being low-level obese (assuming other major risk factors like smoking are in check) may not be quite as terrible as we thought.

 

Also, greater physical activity and higher quality diets do improve health regardless of weight and total calories, and there will be people who remain overweight and show no signs of metabolic issues (“healthy obese”), at least for a while.

 

Unfortunately, “healthy obese” is usually a temporary state. A large, 20-year cohort study came to a disheartening finding: 

 

"After 20 years, approximately one-half of healthy obese adults were unhealthy obese, and only 10% were healthy non obese. Healthy obese adults were nearly 8 times more likely to progress to an unhealthy obese state after 20 years than healthy non obese adults... The natural course of healthy obesity is progression to metabolic deterioration."

Once the metabolic deterioration starts, especially in those at higher levels obesity, the costs are significant. Obesity is directly correlated with higher mortality, high blood pressure, type 2 diabetes, heart disease, stroke, and numerous other conditions. The total costs attributed to obesity are estimated at $147 billion a year in the US alone, and obesity is rapidly becoming the single greatest source of ill health in the Western world. In other words, it is a big deal.

What About Bariatric Surgery?

The one major issue I haven’t addressed from the headline article is the question of bariatric surgery. Bariatric surgery works by reducing the size of the stomach, mechanically limiting how much we can eat. For reducing bodyweight and resolving both obesity and its secondary consequences, it has proven remarkably effective. Is it, as the New York Times would suggest, the best and only real option for the very-obese? 

 

Bariatric surgery has improved a lot over the years, and the surgery itself is relatively safe, but there’s a risk any time you cut someone open, and those risks don’t stop with the surgery itself. 5-10% of people will experience serious short-term serious complications, and it must be carefully monitored in the long term. Because the diet itself is so dramatically reduced and the gut mechanics change, micronutrient deficiencies are common. In addition, due to the sudden loss in body mass and preexisting parathyroid issues common in extremely obese patients, there is a higher risk of osteoporosis. In short, a patient will likely have to manage their diet, supplementation, and medical status for the rest of their life.

 

What does this all mean? There are some people for whom bariatric surgery is appropriate, especially those with a BMI over 40 who have previously tried diet and exercise strategies and would otherwise simply continue on as before. Doctors should stay informed about the risks, rewards, and contraindications and be willing to discuss them with their patients or refer when appropriate. 

 

Dieting and failing in cycles is painful and potentially harmful. If the options are disordered eating, early morbidity and disease, or bariatric surgery, talk to your doctor because it may be right for you. But ignore the naysayers who insist that outside of bariatric surgery, you’re doomed to fail (I’m looking at you, Gina Kolata). 

 

Aren't You Being A Little Harsh?

The Health at Every Size principles statement “rejects judgments about health and any discourse about individual responsibility around health.” They do this to prioritize self-esteem and promote empowerment: if you are not responsible for your health, you don’t have to be ashamed of yourself regardless of how you look or what medical condition you may have. From this starting position, you can then consider options to work towards well-being. 

 

I sympathize with this approach, I really do, and all these articles and videos come down to this: 

• No one should be shamed, mocked, or ridiculed for their weight or health. Shame is rarely a good motivator and often makes it harder to change.
• Everyone deserves informed autonomy; the choice to decide whether or not change is worth the cost. 
• Everyone deserves respect and dignity, not bias and discrimination.
• No one has to meet an arbitrary beauty standard to be happy.
• Some people will be overweight or obese through circumstances entirely outside of their control or due to life challenges that would overwhelm most mere mortals.

 

All of these are true, but none of them can change the facts: we are responsible for our actions, and our actions have a great impact on our health. Although we are influenced by other factors, we are the masters of our fate. Our culture didn’t eat that donut. Our genetics didn’t force us to marathon The Walking Dead when we promised ourselves we would train. 

If we don’t prioritize health, that is our choice and our right, but we are not “entitled to make up our own minds about what 'health' means.” A cell is insulin resistant or it is not. Your cancer is benign or it is not. Obesity (especially without serious muscle mass) saps our health and vitality.

 

But how do we take responsibility for our health without identifying with it? How do we get fitter without feeling ashamed about not being fit already? We accept where we are, move in the direction we commit to, live in each moment, and accept the process. 

 

We would never judge a child learning to walk or mock someone learning a language for making a mistake, and we can apply this same principle to ourselves. By living in each moment, learning from our mistakes, and accepting where we are on the road to progress, we can retain our dignity without surrendering to fate.

 

How can you sort through all the conflicting science out there?

TheRealFitnessninja.Blogspot.com

 

By : CJ Gotcher

http://breakingmuscle.co.uk/uk/fitness/all-diets-fail-why-bother

References:

1. US Department of Health and Human Services. "Reducing tobacco use: A report of the surgeon general." National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health (2000).

2. Cummins, Steven, Ellen Flint, and Stephen A. Matthews. "New neighborhood grocery store increased awareness of food access but did not alter dietary habits or obesity." Health Affairs 33, no. 2 (2014): 283-291.

3. Elbel, Brian, Alyssa Moran, L. Beth Dixon, Kamila Kiszko, Jonathan Cantor, Courtney Abrams, and Tod Mijanovich. "Assessment of a government-subsidized supermarket in a high-need area on household food availability and children’s dietary intakes." Public Health Nutrition 18, no. 15 (2015): 2881-2890.

4. Dubowitz, Tamara, Madhumita Ghosh-Dastidar, Deborah A. Cohen, Robin Beckman, Elizabeth D. Steiner, Gerald P. Hunter, Karen R. Flórez et al. "Changes in Diet after Introduction of a Full Service Supermarket in a Food Desert." Health Affairs (Project Hope) 34, no. 11 (2015): 1858.

5. Dubowitz, Tamara, Madhumita Ghosh-Dastidar, Deborah A. Cohen, Robin Beckman, Elizabeth D. Steiner, Gerald P. Hunter, Karen R. Flórez et al. "Diet and perceptions change with supermarket introduction in a food desert, but not because of supermarket use." Health Affairs 34, no. 11 (2015): 1858-1868.

6. Hobin, Erin, Heather Lillico, Fei Zuo, Jocelyn Sacco, Laura Rosella, and David Hammond. "Estimating the impact of various menu labeling formats on parents’ demand for fast-food kids’ meals for their children: An experimental auction." Appetite 105 (2016): 582-590.

7. Rising, Camella J., and Nadine Bol. "Nudging Our Way to a Healthier Population: The Effect of Calorie Labeling and Self-Control on Menu Choices of Emerging Adults." Health Communication (2016): 1-7.

8. Lee, Morgan S., and Joel Kevin Thompson. "Exploring enhanced menu labels’ influence on fast food selections and exercise-related attitudes, perceptions, and intentions." Appetite (2016).

9. Flegal, Katherine M., Brian K. Kit, Heather Orpana, and Barry I. Graubard. "Association of all-cause mortality with overweight and obesity using standard body mass index categories: a systematic review and meta-analysis." JAMA 309, no. 1 (2013): 71-82.

10. Blüher, Matthias. "The distinction of metabolically ‘healthy’ from ‘unhealthy’ obese individuals." Current Opinion in Lipidology 21, no. 1 (2010): 38-43.

11. Bell, Joshua A., Mark Hamer, Séverine Sabia, Archana Singh-Manoux, G. David Batty, and Mika Kivimaki. "The natural course of healthy obesity over 20 years." Journal of the American College of Cardiology 65, no. 1 (2015): 101-102.

12. Finkelstein, Eric A., Justin G. Trogdon, Joel W. Cohen, and William Dietz. "Annual medical spending attributable to obesity: payer-and service-specific estimates." Health Affairs 28, no. 5 (2009): w822-w831.

13. Schauer, Philip R., Bartolome Burguera, Sayeed Ikramuddin, Dan Cottam, William Gourash, Giselle Hamad, George M. Eid et al. "Effect of laparoscopic Roux-en Y gastric bypass on type 2 diabetes mellitus." Annals of Surgery 238, no. 4 (2003): 467-485.

Cranky Fitness: Will Restricting Carbs Make You a "Fat-Burning Beast?"

So for years I've been intrigued by notion of "Fat Adaptation," a concept advanced by Mark's Daily Apple and others. The idea is that by strategically restricting carbohydrates, you can reprogram your body to use fat as fuel instead of glycogen.

According to Mark:

If you’re fat adapted, the genes associated with lipid metabolism will be upregulated in your skeletal muscles. You will essentially reprogram your body. 

With that comes great benefits!  Like more energy available during exercise and throughout the day, and an easier time burning fat and losing weight than if you are a "sugar burner."

However, most mainstream nutritional advice says almost the opposite: Watch the fat, eat more carbs. These experts claim you need a crapload of carbs for optimal nutrition, especially if you are doing something athletic.  

And yeah, everyone agrees you need protein and that you should avoid refined and processed foods as much as possible and you should be eating plenty of produce.  But as to what else you should be fueling with, the "Are Carbs Good or Are They Bad" debate rages on.

I got so tired of hearing the contradictions that I asked Tiffany Reiss what she thought.  As regulars may recall, Tiffany is a smarty-pants professor type who knows a lot about exercise physiology. (Her bio is below).

So, is her answer simple and straightforward?

Hell no! Because it turns out it's a complicated question!

So those of you who like to geek out, here's Tiffany take on the whole "Should I restrict Carbs" question.

--Crabby

To Carb or Not to Carb

It’s such a simple question: Are carbs good or are they bad? Should we eat them or shouldn’t we?

The answer is: Yes….and No. It depends. So what does it depend on? Genetics, muscle fiber type, activity level, activity type, gut microbes and age to name a few. For now I will just focus on the genetics of it all.

Genetics/Epigenetics

You are your genes, and your environment impacts your genes. We all have a genetic construct and everyone’s is slightly different.

But we now know that our environment influences our genes by turning some genes on and some genes off. It turns out both nature and nurture play roles in who we are and what we ultimately become.

What’s important is which genes are turned on and active, and that can be influenced by our environment. What constitutes our environment? Diet, activity, stress, smoking, exposure to chemicals, toxins, etc… Pretty much how and where you live your life. These are actually new fields of study called: Epigenetics and Nutragenomics. How our environment influences our genes (Epigenetics) and how what we consume influences our genes (Nutragenomics).

Now why is this important? Our bodies adapt. They are amazing machines that adapt pretty well to the myriad of environmental stimuli to which we expose them, if we have the genes that can adapt or turn on/off based on the environmental stimuli. Below is a good example of an adaptation:

Muscle Fiber Type/Activity Level/Activity Type

Your muscle fiber type is genetic. There are 2 basic types of muscle fiber tissue:

• Type I: endurance oriented and aerobic (long distance running, swimming, biking, yoga, etc….)
• Type II: strength/power oriented and anaerobic (resistance training, football, sprints, baseball, etc….)

You get the picture. Type 1 tissue dominates during long duration, lower intensity activity; Type II during short duration, high intensity activities.

Most people are a good combination of Type I and Type II and there are varying levels of isoforms that actually give us a broad spectrum or range of that muscle tissue based on the way we train or exercise. They may vary a bit one way or the other, say 55% Type I and 45% Type II, but the average individual is a good mixture.

Then there are individuals who are less balanced. One individual may be 75% Type I and 25% Type II or vice versa. They are predisposed to excel in a particular type of activity, whereas the more evenly balanced individuals will be good at both kinds of activities (and some sports like say soccer). More Type I than Type II will naturally excel at endurance oriented events. Switch it and you have a great linebacker, 100 m sprinter or running back in football. Of course, the percentages vary, but they influence our ability to gain muscle mass, efficiency in oxygen utilization at the cellular level, excel in different types of sports or activities.

But, coming back to the original question: muscle tissue composition will also dictate which substrate (carbs or fat) we like to use both at rest and during exercise.

In general, Type I muscle fiber tissue likes to burn fat as a fuel source when it is activated, and Type II likes to burn carbohydrate as a fuel source when it is activated.

So how can we tell the difference between Type I and Type II muscle fiber tissue, and what happens when we exercise?

Enzyme concentration and number of mitochondria are a piece of that puzzle. Type I has a lot more mitochondria…and you know what mitochondria do? Mitochondria help the cell utilize oxygen efficiently and the energy system that primarily can burn fat as a substrate is located within the mitochondria.

Type II muscle fiber on the other hand has way fewer mitochondria, doesn’t require oxygen to provide energy (hence their anaerobic nature) and have lots of enzymes to breakdown, you guessed it: glucose (or carbohydrate).

But what happens when say someone who happens to have more Type II muscle fiber tissue trains to run a marathon? This is where epigenetics comes into play. By training more aerobically, some of the Type II muscle tissue will start to become more like Type I muscle fiber tissue. Not all of it will convert and it won’t convert all the way but it will start adding mitochondria and fat burning enzymes while decreasing some of the factors associated with it being anaerobic. It will become more like Type I but to date there is no evidence it will become 100% Type I.

Now of course, muscle cells don’t just start adding more and larger mitochondria and fat burning enzymes, this has to initially happen at the genetic level. Once this individual stops training for the marathon, or completes it ideally and stops training for endurance, those genes will turn back off and back to the Type II muscle fiber tissue that is more, let’s say natural for that individual. This person, although well trained, will never be as efficient at endurance activities as the more Type I individual and there is some evidence, some people (up to 20% of the population) just don’t have the genes to convert at all. So regardless of all of the endurance training, they never increase the number or size of the mitochondria and can’t produce more enzymes for burning fat. 

Why is this important? Well, when engaging in lower intensity, longer duration activities (even sitting at your desk) our bodies prefer to burn fat, how much fat will depend on genetics and muscle fiber type. Burn more fat at rest and during exercise = ability to consume more fat throughout the day.

It makes sense that someone with more Type I muscle fiber tissue will likely burn fat more readily than someone with more Type II, even if they train for endurance oriented activities both at rest and during activity. Ironically, our brains (which actually suck up a lot of daily energy needs) prefer carbohydrates (glucose) as does Type II muscle fiber tissue. So individuals with more Type II, even at rest are likely not very efficient at burning fat and prefer glucose. Which means those individuals likely would do better consuming less fat and more carbohydrates (the good kind of course). 

Consumption of Carbohydrates, Fat, and Protein

We adapt to our environment.  Some better than others.  We can up-regulate and down-regulate hormones and enzymes, change cellular structure (which changes efficiency of substrate utilization), all by changing our activity patterns (Epigenetics) and something else: what we consume (Nutragenomics).

So a logical question is “If I consume less carbohydrate and more fat (and protein) will my body adapt by becoming more efficient at utilizing that fat; will I then burn more fat?  Again, if the genetics allow for it, yes!  If not, not so much.

It’s important to remember here that both your brain and your muscle tissue use about 20% of your total daily energy needs respectively and for the muscle tissue that only increases when you are active. So ultimately what kind of muscle tissue you have, or can shift via training will play a role in your ability to burn fats and/or carbohydrates efficiently both at rest and during activity.

The real problem with carbohydrates seems to be the kinds of carbs we are consuming in the standard American diet.  Way too much sugar and processed carbohydrates and way too few vegetables, fruits and whole grains.   That however, is an entirely different post.

Dr. Tiffany Reiss is an an exercise physiologist and adjunct faculty member at Seattle University, Lake Washington Institute of Technology, American Public University and Walden University. She is also a contributor for the Sports and Fitness Network and the co-founder of TheHubEdu: A Learning Library.

What do you guys think about carbs?

By Tiffany Reiss; With a Long-Winded Intro by Crabby McSlacker

http://www.crankyfitness.com/2014/07/will-restricting-carbs-make-you-fat.html