Just read an article discussing a recent study that found an association between mercury and high fructose corn syrup (HFCS). HFCS, which is chemically just a smidge different than your run-of-the-mill table sugar, has been much-maligned in recent days being characterized as the reason Americans have such poor health. To combat this image, the corn industry has been raining down propaganda in the form of asinine commercials that browbeat apparently clueless HFCS-naysaying nincompoops by reinforcing that HFCS, like regular sugar, is natural (it’s made from corn!) and “fine in moderation” (Examples here and here). This HFCS propaganda has humorously spawned a number of youtube spoofs (See here, here and here). God bless the internet.

I won’t delve into this debate other than to say that sugar, HFCS, pure glucose, pure fructose or just sucrose, all have similar, blood-sugar and insulin-spiking effects, which may have drug-like consequences for the human body, and only offer raw energy (But no other nutrients). And one more thought: the appeal that “everything is okay in moderation” is little more than a meaningless justification for behavior, which due to its vague effectiveness at silencing criticism, actually leaves an otherwise meaningful debate worse off than before the “appeal to moderation” is made.

Back to the article. Here’s the gist of the study:

In the first study, researchers found detectable levels of mercury in nine of 20 samples of commercial HFCS. The study was published in current issue of Environmental Health.

In the second study, the agriculture group found that nearly one in three of 55 brand-name foods contained mercury. The chemical was most common in HFCS-containing dairy products, dressings and condiments.

The use of mercury-contaminated caustic soda in the production of HFCS is common. The contamination occurs when mercury cells are used to produce caustic soda.

The last two sentences are worth reading twice.

Caustic soda (Sodium hydroxide) is a chemical base (OH) used to effect various chemical reactions (often used in paper/textile industries). I don’t know the exact use of caustic to create HFCS from corn, but suffice to say that whatever magic is used requires a chemical base as an intermediate. Caustic soda is most commonly formed as a by-product of chlorine extraction from brine (salt water). There are various ways to separate the Chlorine (Cl) from brine, which leaves behind the NaOH, but one process of chlorine/caustic production involves using mercury cells (Notably, the word on the street is that mercury cell chlorine/caustic production technology is slowly being phased out). Apparently, some of this mercury is leaking into the HFCS, and thereby leaking into any foods that contain HFCS. Yikes.

However, all of the above is more than you need to know because the big takeaway is fairly elementary: HFCS is produced by man. It aint natural (appeal to nature)! HFCS has to be created via any number of chemical processes, one of which requires caustic soda, a chemical that may be contaminated with mercury, which may pass on to the HFCS. It’s complicated.

Cane and beet sugar require processing, too, though the processing seems less complicated and doesn’t require caustic soda (Though it does require chemical enzymes!).

So what does this mean and what should we do about it? Is HFCS the evil sweetener health-advocates love to hate? It certainly gets an extra strike against it for the mercury. Is cane/beet sugar better? Probably. Really, these questions are detractors from the bigger reality, which is twofold. The first is obvious: sugar is unhealthy (no matter the specific form). The second is that the production methods used to create processed foods can introduce harmful mystery ingredients. In short, processed foods are not natural.

Yes, the “natural” criticism is a tautology and a non sequitur. Processed foods aren’t inherently unhealthy and can often times be quite good for you (Coconut oil, red wine, extra virgin olive oil, vitamins). It would be silly to construct a diet that insists on totally abstaining from processed foods. When you get right down to it, even raw honey is processed by bees. Nutrition is much too complex for bright-line rules.

But that doesn’t stop us from creating them. As a rule-of-thumb, the farther a food gets from a virgin state, the more exposure it has to being modified in ways we don’t understand and can’t expect to know. Rather than spend countless hours getting comfortable with each and every processed food item and ingredient (And the processing these ingredients underwent ad infinitum), I can simply follow food preferences that minimize my exposure to the unknown.

In theory, by deferring to “natural” foods over produced foods, I should get so many nutrients and health-benefits from consuming nutrient-dense meats, fruits and vegetables that my body will be keyed to overcome whatever other junk manages to sneak into my diet (Chocolate, coffee, ice cream — little vices).

In practice, to the extent that it’s reasonable to do so, I already avoid HFCS and sugar. I do this by enjoying more natural, tasty and self-prepared meals over processed alternatives. Should I worry about the mercury that sneaks into the store-bought ice cream via the ubiquitous additive, high fructose corn syrup? Naah. If you maximize your health in simple ways, you get the by-product of minimizing the impact of the unknown — all without worrying about the nitty gritty details! So the big takeaway of this study? Stop worrying about HFCS and start preferring better, less processed foods! The rest will take care of itself.

Update 2:24 PM 1/28/09: Not surprisingly, the Corn Refiners Association (CRA) has released a statement to refute the above-cited study on mercury in HFCS. Here’s their side and a snippet:

?This study appears to be based on outdated information of dubious significance. Our industry has used mercury-free versions of the two re-agents mentioned in the study, hydrochloric acid and caustic soda, for several years. These mercury-free re-agents perform important functions, including adjusting pH balances,? stated Audrae Erickson, President, Corn Refiners Association. ?For more than 150 years, corn wet millers have been perfecting the process of refining corn to make safe ingredients for the American food supply.?

The CRA is their own worst enemy here. First off, “outdated information of dubious significance” is a pretty strong statement that is no way backed up by the rest of their press release. The study cited above used samples from 2005, which is recent enough for me to consider relevant.

I also found it odd to read how the CRA speaks for all corn refiners in saying “[o]ur industry has used mercury-free versions.” How do they know that? Do they strictly enforce that all corn refiners only buy caustic soda, a globally-produced commodity chemical, from non-mercury-cell producers? We aren’t told. What we are told is that the FDA has approved HFCS and that it uses re-agents for refining and refining has been going on for 150 years. Breath a sigh of relief!

I updated this post to include the CRA response to point out that there are powers that are out actively talking their books — that includes both the HFCS-cheerleaders and the anti-HFCS activists. Thankfully, us enlightened folk can rise above their lunacy.

Quick take — If you diet or are planning to start a diet, understanding the relationship between bodyweight and glycogen (Glycogen is carbohydrates as stored by your body) depletion is paramount.

Your body stores energy as fat and glycogen. Whereas fat stores can vary dramatically from person to person, your body can only store so much energy as glycogen.

Glycogen requires water to be stored. In the initial stages of diet/caloric restriction and exercise, your body depletes these glycogen stores, reducing your bodyweight from the elimination of both the weight of the stored glycogen and the weight of the water. Note that nowhere in this process is the much-desired loss of fat!

Thus, even as it will feel good to shed 5 - 10 lbs. simply from a few days of exercise mixed with a caloric-restricted diet, the weight loss will be primarily from a reduction in glycogen stores and water. In other words, what you’ll have lost in the beginning is really little more than water weight.

Take heart in understanding the relationship between glycogen stores and bodyweight as an improved understanding will help you set realistic expectations on whatever diet or exercise regiment you are undertaking in 2009.

A deeper dive:

I first learned about the relationship between stored carbohydrates and water retention from Gary Taubes’ Good Calories, Bad Calories. The gist is that for every gram of stored carbohydrate (Stored as glycogen) in your body, there is a set amount of additional water storage that is required.

Taubes had pinned the carb/water storage ratio at two grams of water per one gram of carbohydrate. A random Googled source pins it at 2.7 gram water per gram of glycogen. I found a research paper titled, Glycogen storage: illusions of easy weight loss, excessive weight regain, and distortions in estimates of body composition, which offers the following data on the ratio:

Glycogen is stored in the liver, muscles, and fat cells in hydrated form (three to four parts water) associated with potassium (0.45 mmol K/g glycogen). . . .

Glycogen losses or gains are reported to be associated with an additional three to four parts water, so that as much as 5 kg weight change might not be associated with any fat loss.

Lyle McDonald of Body Recomposition has also weighed in on this subject:

Carbohydrate (stored in your muscles and liver as glycogen) is accompanied by a good bit of water. For every gram of glycogen stored, you store anywhere from 3-4 grams of water with it.

How does this relationship affect bodyweight? In short, diet and exercise will deplete glycogen stores. If your diet is working, the depletion will occur early and have a significant impact on your bodyweight without impacting a permanent change in your body composition.

Let’s take me as an example. I estimate that I have around 155 - 160 pounds of lean tissue. Tack on another 12 - 17 pounds of fat. After a week or two of being on a low-carbohydrate diet that involves intermittent fasting and plenty of exercise (see here), my liver and muscle glycogen stores will be completely depleted. I’ll weigh about 172.

If I go on to eat a bunch of carbohydrates — cookies, pretzels, breads, fruits and other starchy foods (by eating a bunch, I mean consuming something on the order of 1000 grams of carbohydrates over the course of 24 hours, which is about 4000 calories), I will fully replenish my glycogen stores. In the process of replenishment, the 1000 grams of carbohydrates will require anywhere from 3000 to 4000 grams of water for storage! Converting from grams to pounds, the impact on my bodyweight should be an increase of 9 to 11 pounds, taking my weight up to 183*! Of course, the same change would happen in reverse: re-depleting glycogen stores would drop my weigh back to the low 170s.

Mike over at the IF life alluded to this fact in three bullets back on his Trainer Tells All post:

Muscle size is mostly glycogen and water . . . I can go up and down 10lbs in a week easily depending on glycogen and water balance . . . The first big amount of lbs you lose in the first week dieting is mostly water

Mike’s anecdotal experience is explained by the storage ratio between glycogen and water. What it means is that in the early stages of a diet, the magical drop in bodyweight will be mostly water weight.

Another implication of the water/glycogen relationship on bodyweight is that whereas the first 4000 calorie deficit you create will reduce your weight some ten pounds, the next 4000 calorie deficit is likely only going to reduce your bodyweight a paltry two pounds! This is because a pound of fat stores 3500 calories and requires about a pound of water for storage. Thus, the initial weight-loss will seem easy compared to the drudging continued weight-loss when you’re actually burning stored fat.

Failing to understand what is going on with glycogen stores and water retention will set yourself up for a shock when you inevitably “fall off the wagon” – even if the “fall” is only for a day or two of heavy-carb or more “normal” eating.

Understanding the impact of glycogen depletion/repletion on bodyweight is just one more reason why merely weighing yourself on a scale provides a poor indication of your body composition. You’re better served by taking some physical measurements (waist size, for example). Or even better, take some periodic camera phone self-portraits — over time, you should be able to compare them and get a great feel for your progress (or lack thereof).

* I’ve witnessed this fluctuation on numerous occasions over the past year, but I didn’t quite fully understand it until today. You see, I was fully glycogen depleted going into New Year’s Eve. I proceeded to go on a pre-planned “refeed” (that just happpened to coincide with NYE, of course!). The refeed involved eating plenty of pretzels, chips, breads, fruits, cookies, cereal, donuts, etc. Some incredibly unhealthy, albeit tasty, foods. I also drank a good bit of Pinot Noir NYE, which is the opposite of what you should do if you are re-feeding in that your body will be needing water and alcohol will dehydrate you past certain levels of intake. Anyway, after a 24 hour refeed, my bodyweight went from 172 to 184. Hard to believe unless you understand what is going on. And this kind of fluctuation would be entirely disheartening to the ignorant dieter who might feel they just blew their diet in one day! As it is, I expect I’ll be back in the low 170s within five days after I do a fast and get two or three workouts in.

Further reading:

• Michael Van Cise does a deep dive on Taubes’ and water weight

I just finished up a project for Richard Nikoley, friend and founder of Free the Animal. Richard had commissioned me to create a banner for his site, and after hashing out the concepts, I worked on putting together a design.

Here’s the final product:

Some of the ideas the banner is intended to convey are:

• Man as a self-reliant, rugged individual — a hunter — evolutionarily designed over the eons.
• That a man’s health is dependent upon his understanding the nature of his genes and putting that knowledge to practical work in a modern age, an age that is drastically different from the gross majority of man’s biological existence on this planet.
• Human beings are a dominant, independent species, one meant to be free.

Many of these ideas weren’t spoken when Richard asked me to do this design — that is because many of them were already understood. One thing Richard talks little about these days on FtA is his philosophical stance, which centers heavily around an understanding of human beings.

Human beings are intelligent animals. Our intelligence sets us above all other species, but it also enables us to reflect introspectively about our place with regard to the planet and to each other. Such reflection inescapably leads to an understanding that man should be free, both unbound by other men and unwilling to forcibly control his fellow man*. Moral implications aside, it’s this introspection on our nature that leads us to understand how we should approach our health.

Modern man (post-agriculture) has existed for only a handful of millenia, whereas we were evolutionarily designed over some two million years (To say nothing of the millions of years of evolution that occurred prior to homo sapiens). Evolution gave us genes that function best under certain conditions. It’s reasonable to assert that those prehistoric conditions involved a certain amount of activity (i.e. hunting, gathering, play), some amount of scarcity (inability to find food leading to periodic bouts of famine) and substantially limited agricultural technology. How these inputs and constraints molded our genes is a fundamental question worth asking. Free the Animal tackles this question for the purpose of living optimally, as modern men with ancient genes.

“Free the Animal” is a motto. And Richard is expanding on what it means to free the animal his site. Be sure to check it out!

^* Except in cases where force is required to defend himself or his property.

Is sugar another addictive white powder?

A recent study suggests sugar may be addictive. Below are parts of the U.S. News article summarizing the experiment and interpretation of the findings. I suggest reading them all:

“Our evidence from an animal model suggests that bingeing on sugar can act in the brain in ways very similar to drugs of abuse,” [said] lead researcher Bart Hoebel . . .

“Drinking large amounts of sugar water when hungry can cause behavioral changes and even neurochemical changes in the brain which resemble changes that are produced when animals or people take substances of abuse. These animals show signs of withdrawal and even long-lasting effects that might resemble craving,” . . .

A “sugar addiction” may even act as a “gateway” to later abuse of drugs such as alcohol . . .

For the new research, rats were denied food for 12 hours a day, then were given access to food and sugar (25 percent glucose and 10 percent sucrose, similar to a soft drink) for 12 hours a day, for three to four weeks.

The bingeing released a surge of the neurotransmitter dopamine each time in the part of the brain involved in reward, the nucleus accumbens. “It’s been known that drugs of abuse release or increase the levels of dopamine in that part of the brain,” Hoebel said.

But it wasn’t only the sugar that caused this effect, Hoebel explained – it was the sugar combined with the alternating schedule of deprivation and largesse. . . .

But longer periods of abstinence didn’t “cure” the rats. Instead, there were long-lasting effects with the animals: They ingested more sugar than before, as if they were craving the substance and, without sugar, they drank more alcohol.

My anecdotal experience confirms the above findings. For one, the more I have abstained from sugar and refined carbohydrates (the latter of which are one tiny step away from being sugar), the easier it has become to strictly avoid sugar/carbohydrate-dense foods. This suggests to me that the addiction can be controlled by almost completely abstaining from the “drug,” sugar in this case.

Of note, however, is that in those instances when I have fallen off the wagon^* and started eating sugar/refined carbs, I tend to overeat/binge. Is this the behavior of an addict? Or is it the psychological response to the forbidden fruit? Or is it a predictable response of treating a diet like a binary system? I.e. going from strict adherence to the diet to “Well I already ate that candy, might as well have some ice cream, too!” Any of these are plausible explanations for my behavior.

The alcohol angle is fascinating: I’ve experienced a clear connection between alcohol and carbohydrate-binge-eating. As before, I am unclear how the alcohol is catalyzing my reaction — is it that alcohol impairs my judgment, handicapping my will power? Or could it be more fundamentally metabolic — the alcohol spurs a chemical reaction resulting in craving sugar/refined carbohydrates? Why do I go from having little-to-no craving for French fries and tator tots to no-holds-barred “pass the ketchup now!” after downing three or four beers.

I have previously blogged on how hard liquor has zero carbohydrates. I’ve since learned that hard liquor (i.e. whiskey) will cause an insulin response even though there are no carbohydrates in the alcohol. Could insulin have something to do with this^#?

This study, rather than confirming something I’ve suspected about the addictive nature of sugar, leaves me with more questions than answers. Is modern man doomed to be addicted to sugar? Is sugar addiction similar to alcoholism in that the only successful means to control the addiction is to avoid entirely the addictive substance? Can abstaining from sugar/refined carbohydrates make the addiction worse? Is sugar a poison that should be taken in small doses to control its ill-affects (A particularly strange notion)?

It seems there are more questions than answers. However, I maintain that sugar in any close-to-raw form is unnatural, which means that our evolutionarily designed bodies are inept at handling it. And it seems reasonable to conclude that, even if I tend to overeat refined carbohydrates when I do consume them, over the long-term, I’m still drastically reducing my intake of sugar and refined carbohydrates by maintaining a lifestyle focused on a low-carbohydrate, natural diet mixed with intermittent fasting.

^* How often have you heard the phrase “fallen off the wagon” to describe failure at dieting? I hear it all the time (and use it). Probably just a coincidence, this phrase originates in alcoholism. Here we have a study that paints sugar as being similar to alcohol in its addictive characteristics.

^# I can’t help but wonder if insulin is the culprit behind addiction to both alcohol and sugar. Has anyone looked into this?

I love eggs. They can stand in as a meal in a pinch, whether it be for breakfast, lunch or dinner. You can boil them, fry ‘em, scramble them, make an omelette or a frittata. If you take certain precautions, you can even microwave them. For my go-to breakfast, I personally switch between overeasy and sunny-side up, mixing it up between butter, coconut oil and fresh bacon grease.

I like eggs so much that I often keep a few recently boiled eggs in the fridge for a tasty, healthy, filling snack. I think eggs make such a great snack that the idea of inventing an Egg Vending Machine has crossed my mind — imagine being able to drop 50 cents into a machine and get a piping hot boiled egg in return? Hmm …

What brings me to discuss eggs is a recent post by Richard Nikoley at Free the Animal. Richard is also a big fan of eggs — yolk and all, just like me. This is an important point you shouldn’t miss! Don’t throw out the yolks! Why? Because that is where all the good stuff is (I.e. protein, vitamins, fat)! What about the cholesterol? If you have to ask … read the quoted material at Richard’s site.

Richard also links to a post that talks about the difference between factory produced eggs (the one’s you get at a grocery store) and the ones produced by chickens that cluck around on a farm (eating whatever they happen to find and not all grain). A picture is worth a thousand words, so be sure to note the difference in the egg at the top of the frying pan and the other four here.

The big dilemma I have is: how do I get my hands on fresh, real eggs like that? Farmer’s market maybe? Get my own chickens? Any bright ideas?

Having returned from India and a month-long hiatus from eating healthy and working out, I started brewing on a strategy to “get back at it” and continue working to my ultimate goal, which is achieving never-before-seen (on me) lean-ness and vasculature.

My approach for most of the summer had been working out about five days a week (doing CrossFit) with daily fasting (i.e. 16 hour fasts daily). I tracked a lot of my daily workouts via my workout blog.

Unfortunately, I ran into any number setbacks as I had a couple long periods where I couldn’t manage to eat right or workout (A two week stint out west and a three week stint in India).

That brings me back to today. I’m going “back to basics,” which for me, was eating breakfast/lunch and the fasting until dinner the following day, with a weight-lifting oriented workout an hour or two before breaking my fast. This method worked for me the first time, stripping away a great deal of fat and focusing my diet/weight-training efforts. This time around, the only tweak I’m implementing is that I will do two fasts per week, lifting on days I break the fast, working out on days I eat, and resting on any day I begin a fast. Per usual, my diet will be carb-light, which means no breads, rices, cereals or starchy vegetables while still allowing for most fruits (apples and berries being preferred), some cheats (ice cream), and alcohol.

Goal is to try this for three weeks, track my progress daily and see how I come out on the other end. Stay tuned.

Cortisol has been a bit of a mystery to me. Things I’ve gathered about cortisol include:

• Cortisol is a hormone
• Cortisol is elevated by exercising
• Cortisol is elevated by drinking alcohol
• The presence of cortisol spurs weight gain, and specifically, fat accumulation in the gut for men
• Cortisol can impair the immune system
• Vitamin C before bed (And getting plenty of sleep) can reduce cortisol (See Robb Wolf’s comments on this post)

Some reading on cortisol from the usual suspects:

• Mark Sisson: How Stress Can Make You Fat — The Definitive Guide to Stress, Cortisol, and the Adrenals: When ?Fight or Flight? Meets the Modern World
• Robb Wolf: Exercise: Ineffective for Weight Loss — Robb speaks specifically to those CrossFitters who are also training for endurance-type events.
• Arthur Devany: Mass - Here Art says something about weight lifting for more than 30 minutes at a high pace will elevate cortisol levels.
• Lyle McDonald: How Many Carbohydrates Do You Need - “As few as 15 grams of carbohydrates per day has been shown to limit nitrogen loss and 50 grams of carbohydrate per day severely limits the need for the body to use amino acids for gluoconeogenesis. Not only will it maintain blood glucose and insulin at a slightly higher level (thus inhibiting cortisol release)”

There’s a lot of information out there on the subject of cortisol. As someone who is exercising and periodically imbibing alcohol, how should I deal with cortisol to mitigate its detrimental effects on my goals?

And what is overexercising anyway? What is over-training? If you tack on some low to medium intensity cardiovascular exercise to weight lifting / high-intensity exercise, do you cross the line between “just right” and “too much"? I have no doubt that the answers to these questions are case-specific.

What is a good mix of exercise for a relatively sedentary web entrepreneur?

I subscribed to Mike OD’s The IF Life¹ awhile back. Mike is a personal trainer with years of experience who is a big advocate of incorporating intermittent fasting into your life. However, his site isn’t merely about IF. From what I can tell, the IF Life aims to be a holistic resource on living a healthy and happy life. Mike’s site is a great resource — check it out.

In two recent posts on The IF Life, Mike used the phrase “insulin control” to sum up one of the key tenets of effective diets (See here and here).

In the first post, Mike alludes to the fact that insulin control is the chief goal of all effective diets, whether the diets know it or not (I.e. diets that advocate six meals a day are aiming to control insulin spikes, even if they don’t say so explicitly).

In the second linked post, titled Diet Book Insanity. When did Eating become this Complicated?, Mike states:

Now I know what many may say, but diets can work right? Sure … at the heart of all diets you see 2 main things that will get people results: Insulin control (see the carbs are not the enemy post and insulin and sugar post) and Calorie Deficit Intake (so the body burns from internal fuel sources, which is what you need if you want to burn that stubborn body fat).

Mike smartly tacks on caloric restriction to insulin control as the two overarching diet-advice mantras that tend to get results (Almost certainly so when used together). And though this wasn’t really the point of his diet insanity post (and I know I didn’t coin the phrase), I’m still going to take some credit for distilling the diet madness down to two simple words:

They’re all about insulin control!

Update 09/10/08: Robb Wolf, another blogger I’m subscribing to these days, happened to use the phrase “insulin control” back in October of 2007:

Super simple: Our nutritional recommendations are focused at insulin control. You could also say that our nutritional recommendations are what we are designed to eat and thrive on …

The post is about CrossFit, overexercising, and dialing in nutrition in order to see body composition changes. In my (limited) experience, his post rings absolutely true for me: exercise did little in the way to improve my body composition until I reigned in insulin.

¹ “IF” stands for “Intermittent Fasting", of course, and you gotta love the play on words the acronym creates!

Rusty, founder of Fitness Black Book, tells us that when it comes to lifting weights and building strength, the key is “slow and steady” (See his most recent post, Strength Training Rep). In short, rather than lifting heavy weights in a jerky fashion, which is best exemplified by the near chest bounce on the bench press, you’re better off going through the weight lifting motions in a slow, controlled fashion.

The benefits of slowness in weight lifting include reducing the chance of injury and, according to Rusty, more lasting strength creation. Actually, in reading through the aforelinked post, I’m reminded of Rusty’s post on “Mastering the Weight“, which I particularly found interesting.

Both are good reads with some solid food for thought. For me, the jury is out on this subject and there are all sorts of conflicting opinions. Arthur De Vany seems to be an advocate of more explosive lifting. Unfortunately, I can’t seem to track down the posts where Art advocates as much as it seems Google’s indexing of his site is broken (arthurdevany.com recently underwent a sitewide “upgrade", and it seems that some posts were lost in the change). Art’s argument, if I recall correctly, is that explosive movements are more in keeping with function — i.e. we don’t sprint in slow motion. On the flipside, dead lifting in real life is hardly explosive.

Isn’t there room for both? Methinks yes.

Back to Rusty’s Strength Training Rep post — he had a great explanation on using irradiation to boost muscular definition and strength. Check it out:

The Skill of Generating Tension in the Muscle

Strength is largely determined by your ability to generate tension in a muscle. The harder you can contract a muscle the better strength you can demonstrate in that muscle. Did you know that you can contract a muscle much harder if you also contract the muscles surrounding it? I learned about this principle called “Irradiation” from Soviet Special Forces Trainer, Pavel Tsatsouline. Here is how he explains it.

1. Try flexing your bicep as hard as possible without making a fist.
2. Now try and flex your bicep as hard as possible while making as tight as fist as possible and squeezing.
3. You should be able to contract your bicep much harder when making a tight fist.
4. This is called “irradiation"?what is happening is that the nerve impulses of surrounding muscles can amplify the effect of that muscle.

How to Become a Master at Generating Tension

Here is the craziest thing about the principle of Irradiation. You can actually create stronger contractions in a muscle by flexing a bigger chain of surrounding muscles. Take that bicep example above. Try contracting you bicep as hard as possible but this time don’t only squeeze your fist, but contract your pecs and abs as hard as possible as well. Did you notice a difference? After a while you will become a master at irradiation to reach high levels of strength.

Anyway, some food for thought on this fine Friday. I like Rusty’s site and you should check it out. I’ve been particularly interested in his (and Lyle McDonald’s) approach to stubborn fat loss. You can check Rusty’s mini-book on it here (it is free!).

I stumbled across a blog post titled Conflicting Cardio that pondered aloud the following:

As I read Mark’s essay, I distinctly remembered hearing advice somewhere that completely contradicted what he was saying. I remembered reading that we were actually genetically designed to run long, slow distances, and that the way our ancestors hunted was not in short sprints (antelope would outrun us no problem), but rather in long, slow jogs, waiting for the animal’s body temperature to overheat. At that point, the animal simply passed out from heat exhaustion, and we moved in for the kill. This is based on the premise that human beings evolved an evaporative cooling system, whereas animals didn’t; they don’t sweat, and thus, they’re terribly inefficient at cooling their bodies during exercise.

Fortunately for you, I have a spectacular memory. The article I’m referencing was from an issue of Men’s Health that ran about a year ago, titled Yes, You Were Born to Run. The author, Richard Conniff, based the article on research conducted by Daniel Lieberman PhD, a University of Utah biologist.

I find this situation particularly hilarious because it illustrates perfectly the dilemma that the typical North American finds itself in when attempting to establish what, exactly, is good for us in terms of our health. Is it low-fat or low-carb? Steady-state cardio exercise, or HIIT (High Intensity Interval Training)? 12-15 reps or 6-8? The amount of conflicting information published is astounding.

What is the right combination of cardiovascular exercise and strength-training? Is one better than the other? Is endurance exercise healthy? These are important questions to ask.

Here is my brief take, which is cross-posted as a comment on Becoming Adonis:

Thought-provoking post.

Seems to me that any “cardio” should be conducted at low-intensity. “Intensity” is incredibly vague, so for my purposes, I am defining it as whatever rate at which my body burns mostly fat for energy. For most of us, I imagine fairly low levels of exercise — probably less than jogging but greater than walking (Though walking with weight could serve in a pinch). For individuals who train for endurance, the level will be higher as their bodies are more efficient at burning fat for energy — I’m thinking specifically of Ironman athletes or other high endurance individuals who necessarily blow through all of the glycogen stores in their bodies and simply must burn fat for fuel. For a discussion on this, see Mark Twight’s write-up on endurance and fat (here).

Based on a number of articles about endurance exercise (See More Reading below), I don’t see a lot of benefits in endurance training. I’ll save further discussion on that topic for another time.

Meanwhile, HIIT and/or weight lifting is right up the alley of most all of us mere mortals for the very reasons Mark Sisson and you describe (Sprints being a great example).

How do we put all of this together? Do we just ditch cardio/endurance exercise altogether?

Modern man is scarcely active relative to our ancient ancestors. Hunting/gathering at the grocery store is hardly going to require a lot of energy nor is typing 90wpm or clicking a mouse. The big incongruity is simply a lack of basic, low-intensity activity that would have been a matter of course to paleo man but is a foreign concept to us bloggers.

So what is the solution? We should simply seek to be more active at low-levels of intensity. This means more walking (perhaps weighted) or perhaps low-intensity biking or mountain biking. I imagine there are a number of competitive sports that could also fit the bill here. Mix these activities with HIIT and weight-lifting and you’ve got an optimal combination.

More reading:

• Did you happen to see this post by De Vany on sweating? Totally jives with the evaporative cooling mechanism discussion in your post.
• The Men’s Health article referenced can be found here

And a bevvy of articles on endurance exercise, most which question its health benefits:

• Recent Triathlon Deaths Have Experts Searching for Answers (NY Times)
• Death by Exercise (Men’s Health)
• The Legacy of Jim Fixx (halhigdon.com)
• Running Yourself to Death (The Voice of Prophecy)
• They’ve made it! Seven marathons in seven continents in seven days to help fight heart disease (British Heart Foundation)
• Art De Vany: Top Ten Reasons not to Run Marathons — Coronary Heart Disease in (you guessed it) Marathon Runners — Marathoners and Other Sick People