Before delving into physiology, endocrinology, metabolism and nutrition, I think it's important to discuss four major concepts you'll need to understand and master if you hope to change your own body composition.

1 A three-tiered, integrated approach to fat loss is always warranted yet rarely found.

Magazine articles often cover only one piece of the fat loss puzzle. One article will discuss supplements for fat loss, another will discuss diets for fat loss, and yet another will discuss exercise for fat loss. Now, don't get me wrong; I'm not dissin' the mags. After all, the very nature of the article format is to be brief and cover one topic per article. Yet all this disjointed information can, at best, produce sub-optimal results.

For example, if you were to try to get lean by just popping a few pills, your results would be suboptimal, especially since many supplement approaches increase fat mobilization, but don't improve fat oxidation. In other words, you can pop those fatty acids out of your adipose cells all day long, but if that fat isn't oxidized (via an appropriate exercise plan coupled with a hypocaloric diet), those fatty acids will just be recycled – sent right back to those fat cells from whence they came.

Here's another example of what I'm talking about. If you try to get lean by dieting only, you're bound to see larger decreases in muscle mass than if you'd exercised appropriately during your diet phase. With losses in muscle mass come losses in basal metabolic rate (BMR), decreased exercise and non-exercise energy expenditure, and decreased exercise performance. Not exactly the recipe for long term leanness, eh?

Finally, since most exercise programs don't have enough volume to produce fat loss, in the absence of some sort of energy manipulation (dietary changes) your body composition won't budge much at all. If you don't have time (or the recovery resources) to train for a few hours a day, good luck getting lean while still eating Krispy Kreme!

So in the end, it's only in the integration of diet, training and supplements that the most effective fat loss can occur.

2 The body is an integrated unit, so a comprehensive approach is necessary.

The body is an integrated unit – no system acts independent of the others. As a result, attempting to get lean by micromanaging one body system almost always leads to overcompensation of other body systems and sometimes even metabolic crisis (like health problems and rebound fat gain).

For example, the use of adrenergic supplements (ephedrine, caffeine, clenbuterol) can increase cortisol, reduce glucose tolerance/insulin sensitivity, and decrease leptin. In the short term, you'll still lose fat because adrenergic stimulation is pretty powerful. However, in the long term, there's rebound fat gain once energy restriction, increased energy expenditure, or adrenergic supplementation is removed.

Why doesn't your body better cooperate? Well, your bod likes homeostasis more than it likes visible abs. When you try to manipulate one system to outsmart it, another system kicks in to negate the effects of your first manipulation, or at least it waits in the wings, silently, ready to later correct what you've done. Riding up and down on that fat loss roller coaster sure does make it hard to remain lean in the long term.

So let's talk integration. Here's a diagram showing just how integrated many of the systems of the body really are:

*This slide is adapted from a slide presented by Dr. Rob Rakowski in 2004.

As you can see, this slide shows us that almost all of the hormonal systems of the body are interrelated in some way. Check out how just one hormone (cortisol) can impact the sex hormone systems, thyroid hormone action, insulin and glucose tolerance, and several other endpoints related to physiological and psychological well-being. Since hormones are the messengers communicating with the cells of the body, orchestrating fat loss or fat gain, it's no wonder they've become the target of many drug and supplement strategies.

But it's important not to get too bogged down with hormonal manipulations. Like I said, the body doesn't like when we mess around with a single system or two. Besides, in the end, when we're talking fat loss, the hormones don't matter as much as their net results do. After all, hormones themselves don't make us fat or lean; it's the effects of these hormones that make the difference. So let's talk effects.

When on a hypocaloric (lower calorie) diet, the following three endpoints are likely.

1. Reductions in energy expenditure (exercise and non-exercise)
2. Reductions in muscle mass
3. Increases in appetite

Since these three things are hormonally mediated, we can either try to mess with the hormones (not always a good idea, as addressed above) or we can try to improve the endpoints by attempting to maintain daily energy expenditure, maintain muscle mass, and avoid increases in energy intake.

Therefore, next time you enter into a diet phase, ask yourself – does my fat loss program...

1. Maintain pre-diet energy expenditure? This is accomplished via increased exercise metabolic activity (more cardio, ugh), increased non-exercise metabolic activity (walk instead of drive, pace when talking on the phone rather than sit, chew gum, drink cold water, etc.), and increased cost of exercise and non-exercise activity (i.e. wearing a weighted vest while doing cardio, walking, or doing chores).
2. Incorporate exercise designed to preserve muscle? This is accomplished via more intense, heavier training sessions with lots of muscle specific and CNS specific recovery in between sessions.
3. Manipulate energy intake, food timing and food type to retain a high-energy expenditure and preserve muscle mass? This is accomplished via optimizing energy intake, periodic re-feeds, carbohydrates during and immediately after exercise, increased protein intake, healthy fat balance, etc.
4. Help organize my lifestyle such that I can easily support an energy restriction in the face of increasing hunger? This is accomplished via smart shopping, eliminating tempting, tasty morsels from your home, planning for the unplanned so you're not missing meals and getting ravenously hungry, eating frequently and drinking more water.

When dieting, be conscious of these questions. In doing so you'll be better able to plan for the metabolic mayhem ahead.

3 Focus on optimal health, body composition and exercise performance, plus formation of lasting habits.

Good nutrition programs achieve the intersection of optimal health, optimal body composition, and optimal exercise performance. What do I mean by "the intersection?" Well, check out this diagram below:

Stick around long enough and you'll see all sorts of nutrition programs. You'll find programs that help you improve your health, yet these very same programs will do nothing to improve body composition and/or exercise performance (these plans would be located in the "A" domain above).

In addition, you'll find programs that improve body composition yet don't optimize health and/or exercise performance (the "B" domain above). Finally, you'll find programs that help with exercise performance yet don't optimize health and/or body composition (the "C" domain).

Regardless of which of the three programs you select, none of them are going to be optimal. When looking for the zone of optimization ("D"), you've gotta find a plan that intersects the three goals. A proper nutritional plan will get you there (more on that below.)

4 Ultimate success has little to do with the plan itself but rather its application. In most cases, it's not about the food.

Recently, I published a two-part article here at T-Nation describing how the limiting factor in most trainees' physique progress is their inability to plan for the unplanned – their inability to continue to follow their well-thought out plan in the face of unexpected daily challenges at home and on the road.

This article series is called It's Not About The Food and in it I describe how you can take lessons from superhero Lance Armstrong in order to win your own nutritional Tour de France. The point is this: there's more to physique progress beyond your original meal plan itself. You'll find a few examples of this below.

The next stop on our road to leanness is a brief explanation of fat storage, transport and metabolism. Since this article isn't designed to present an in-depth analysis of fat metabolism, I'm not going to make your eyes go cross with detailed biochemical explanations. Instead, I'm simply going to give you a quick glimpse into this area with a few neat pictures.

In this first image, I'd like to draw your attention to the two major sites of fat storage we're interested in today: adipocytes (fat cells) and skeletal muscle.

It's important to note that these two sites represent two major sources of fat for oxidization or "burning." The other major source of fat for oxidation is dietary fat.

Dietary fat is "burnt" when dietary triacylglycerols are broken down into fatty acids and these fatty acids are transported (bound to a blood carrier protein called albumin) to the muscle cells. Once there, they enter into an organelle called the mitochondrion and undergo a process called beta oxidation. Beta oxidation is what we call "fat burning."

In addition to dietary fat, skeletal muscle triacylglycerols can also be broken down into fatty acids. These fatty acids simply work their way through the muscle to undergo that same process of beta oxidation described above.

Finally, adipocytes or fat cells, can release fatty acids which travel through the bloodstream (again, bound to albumin) and, similar to dietary fat, enter the muscle cells, enter the mitochondrion, and are incinerated via beta oxidation. Since it's the fat in our adipocytes that we want to burn in order to get leaner, let's quickly review how that process happens:

Notice above that certain hormonal signals affect different parts of the fat breakdown process, telling the fat cell to accelerate the breakdown of triacylglycerols into fatty acids or to slow down this process.

Regardless of these hormonal signals, once these fatty acids are broken down they can travel into the bloodstream. This process of removing fatty acids from adipocytes, pictured above, is what we call fat mobilization.

As discussed, the fatty acids released during fat mobilization enter the bloodstream, and their fate depends on a number of factors, including activity level and a number of other hormonal influences. Some fat is burned at the muscle level via beta oxidation while other fat can be recycled back into adipose cells.

Hopefully now you'll understand what I mean when I say that some interventions can mobilize fat (like adrenergic supplements and drugs), but don't necessarily improve fat oxidation. Maximal oxidation is contingent upon both maximal mobilization and maximal metabolic activity (to oxidize those mobilized fats).

One major factor involved in improving fat mobilization from fat cells and the eventual oxidation of that fat, is achieving a negative energy balance. In other words, you need to decrease your energy intake, increase your exercise expenditure, or find some combination of energy intake and energy expenditure that'll allow your body to draw on your stored fat as an energy source.

While this process seems like a no-brainer – just eat less than you're eating now or work out more than you are now and you'll drop fat – I've seen case study after case study illustrating that if someone is at a body fat stalemate (especially when this stalemate is at a low energy intake), sa reduction in energy intake is sometimes the wrong approach!

Sometimes an increase in energy intake (coupled with a change in food choices and nutrient timing) can lead to rapid fat loss. Take for example, an elite female athlete I consulted with back in 2002. Check out her before and after stats:

That's right, in the face of a 1500 kcal increase in energy intake (along with some big shifts in food type and timing), she dropped 23 pounds of fat in 12 weeks!

But be careful – it's not always true that an increase in energy intake will lead to fat loss. This will only work when a client is undereating relative to their actual metabolic requirement (based on activity levels, muscle mass, genetic makeup, etc). Deciding if this is the case is based on dozens of factors.

In the end, while it's easy to tell those trying to lose fat to simply eat less or exercise more, the story is much more complex than that. The traditional picture of energy balance is missing one key facet: the fact that energy intake and expenditure are tightly inter-related. Without understanding this relationship, some erroneous conclusions are regularly drawn by dieters and nutritionists, conclusions that prevent improved body composition.

Next week, in Part 2, I'll cover how much, what, and when to eat.