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How you can improve your body composition: Optimizing fat loss and muscle gain

Wie Du Deine Körperkomposition verbessern kannst: Optimierung des Fettabbaus und des Muskelaufbaus

This article contains specific advice for individuals who are currently carrying around some unwanted body fat on how to approach the fat loss and muscle building process.

Introduction to improving body composition

The goal of most people who work out in a gym is to improve their body composition. The tricky thing is that improving body composition is a process of give and take. For years, many have debated the idea that you can't lose fat and build muscle at the same time because building muscle requires a caloric surplus and losing fat requires a caloric deficit, and you can't be in a state of caloric deficit and caloric surplus at the same time.

This is why the "traditional" approach that many exercisers use to improve their body composition is to alternate between phases of muscle building and fat loss. These phases are also referred to as the mass phase and the definition phase.

So you might think that the overall process is like a seesaw between building muscle and losing fat - if you increase one, the other must be reduced. This is probably the biggest dilemma that competitive bodybuilding and figure class athletes have faced since they first set foot in the iron asylum. Without the use of pharmacological doses of performance enhancing compounds, trying to optimize muscle hypertrophy and fat loss at the same time is a very tedious affair. The other option is a maintenance phase during which you neither gain nor lose muscle or fat).

Applying the above quandary to individuals who are already overweight, it seems intuitive to work on reducing body fat first. While this may be the right approach in some cases, it is not always the ideal way and some overweight people may in fact benefit from working on building muscle first before trying to lose their excess fat.

With this in mind, this guide will cover possible approaches to improving body composition and applying these protocols to overweight (or even obese) individuals. We'll also briefly talk about what the term body composition actually means, take a look at some of the physiology that underlies the breakdown of fat and the building of muscle, and address the need for things like cardio training, resistance training, and proper nutrition.

What is body composition and how can you improve it?

In fitness and bodybuilding terms, body composition is the percentage that fat tissue makes up of your total body mass. At first glance, this seems quite simple, but when it comes to improving body composition, things get a little more complicated.

One thing that people seem to overlook when setting a new fitness or body development goal is the fact that body weight alone is not a sufficient measure of their progress. There are some scenarios where a person's only goal may be to lose or gain weight, but in most cases it is more goal-oriented to focus on improving body composition regardless of overall body mass.

In an ideal world, we would optimize fat burning and muscle building at the same time. But unfortunately, as has already been mentioned, these two goals are essentially contradictory and more or less mutually exclusive. However, this does not mean that you cannot improve your body composition at any given time.

Improving your body composition simply means improving your ratio of muscle mass to body fat tissue (i.e. lowering your body fat percentage). For example, if we take Mr. Shredded and add 5 pounds of muscle but only 2 pounds of fat to his body, then we have improved his body composition. Also, a loss of 5 pounds of fat, with a loss of only one pound of muscle would result in an improvement in body composition.

So to recap, we want to maximize muscle hypertrophy (while minimizing fat gain) or maximize fat burning (while minimizing muscle catabolism).

Optimizing muscle gain

When we look at the goal of building muscle, it's useful to understand what constitutes a state of muscle anabolism/hypertrophy. Basically, this can be reduced to what is known as net protein turnover, which is a quantitative measure of muscle protein synthesis vs. muscle protein breakdown.

If muscle protein synthesis is higher than muscle protein breakdown, this is an indicator of muscle hypertrophy (i.e. an anabolic state) and vice versa. A variety of factors such as training, diet, disease, immune responses, gene expression, pharmaceutical agents, supplements, etc. cause fluctuations in this ratio

So to optimize or maximize muscle gain, we ideally want to maintain a higher rate of muscle protein synthesis compared to muscle protein breakdown (which means muscle protein turnover in favor of anabolism). So it's all very simple. Wait, not so fast - muscle protein synthesis is tightly controlled and regulated via a protein encoded by the FRAP1 gene known as Mammalian Target of Rapamycin (mTOR). (1)

The mTOR protein acts as the backbone of the mTOR protein complex (i.e. mTORC1 and mTORC2) that activates protein synthesis when the necessary cellular conditions are met (and ultimately induces cellular growth and proliferation). (2) As mentioned above, the regulation of the protein synthesis pathway is very complex (and a detailed description is beyond the scope of this article), but it can still be helpful to have this rudimentary knowledge of how muscle cells grow.

The activity of the mTOR protein complex depends on the energy status of the cell, circulating growth factors and hormones (especially insulin), nutrient availability and oxidative stress. Under this premise, the goal for maximizing/optimizing muscle gain is to enhance these factors to upregulate muscle protein synthesis.

Optimizing fat loss

On the fat loss side of things, the mechanisms that are conducive to the process of fat burning are more or less direct antagonists of the mechanisms involved in muscle building (and vice versa). Fat breakdown is regulated in large part by the enzyme adenosine monophosphate-activated protein kinase (AMPk), a trimeric protein produced in many tissue types in the body.

You will probably be aware that adenosine triphosphate (ATP) is the body's energy currency and that the breakdown of ATP produces adenosine diphosphate (ADP) and free energy. AMPk is activated when the cell is in a state of energy deficiency (i.e. the ATP : ADP ratio decreases). This occurs during periods of nutrient deprivation (especially glucose deprivation), ischemia (a lack of blood supply to an organ), during exercise and/or the use of certain chemicals/medications.

In contrast, things like eating and excessive glycogen levels inhibit AMPk activity (as the ATP : ADP ratio is increased).

What does all this mean in the grand scheme of fat loss? Well, AMPk enhances lipolysis, increases fat oxidation, improves glucose uptake into muscle tissue and inhibits lipogenesis (fat breakdown). (3). Basically, AMPk is the metabolic switch for the activation of fat burning.

AMPk and mTOR: a give-and-take relationship

So now we know the importance of mTOR and AMPk when it comes to improving body composition, but the problem is that they are activated by antagonistic mechanisms. Even though AMPk is great for activating fat burning, it also inhibits mTOR (and therefore protein synthesis). (4) Conversely, mTOR inhibits AMPk, which means that fat burning is inhibited when muscle protein synthesis is activated.

If you think about this rationally, this should not be surprising as cellular energy levels at any given time are only either sufficient or too low in terms of ATP : ADP ratio. Although this is a very simplistic way of describing these pathways, it at least gives you an idea of why you can't achieve maximum muscle gain and maximum fat loss at the same time.

However, this doesn't mean you can't switch back and forth between these two states - and in fact, certain protocols such as intermittent fasting, refeed protocols and yo-yo dieting are based on this idea. To improve body composition, it would theoretically be best to activate each of these pathways (AMPk/mTOR) sufficiently, even if only temporarily.

Where should an overweight or obese person start?

While there will always be individual variables at play when it comes to the perfect plan for overweight individuals, there are some general tips to consider if improving body composition is the primary goal. Overweight is a somewhat misleading term, as it does not necessarily mean that a person is excessively fat. This advice is therefore aimed more specifically at people with a high body fat percentage (particularly those above the 20% mark).

You will need to assess yourself honestly and objectively and then decide whether you have a useful base of muscle mass to work with, or whether you need to develop that base first. Some heavier people may already have a reasonable amount of muscle mass but also be too fat (imagine the "traditional" heavyweight powerlifter), while others may be too fat while lacking muscle mass.

Create metabolic leeway for yourself

When it comes to improving body composition, the most important requirement is to increase your metabolic rate as much as possible. One way to achieve this is to first increase your metabolic rate so that you have more room to work with when you reduce your calorie intake. There are several factors that can help you increase your metabolic rate, but the main one we will focus on is building more muscle mass (as muscle tissue requires more energy than fat tissue).

Intuitively, the higher your baseline metabolic rate, the more efficient the process of improving body composition will be. The main reason we want to increase the capacity of your metabolism early on is that prolonged energy restriction will slow down your metabolic rate so that you will eventually reach a plateau and your fat loss will stall.

For this reason, it is crucial to rev up your metabolism before you start shedding excess fat. This doesn't mean that you can't lose fat without working on building muscle first - but such an approach will be less effective in the long run and make the process more difficult both physiologically and psychologically.

How you should approach body composition improvement if you are overweight

Case 1: Fat but useful amount of muscle mass

In the case of a fat but muscular person, it may be appropriate to focus on fat loss first, interspersing temporary periods of maintenance or muscle building. Because such a person has a useful amount of muscle mass, they have a higher metabolic capacity. These people have more leeway to work with when it comes to reducing calories.

As noted earlier, metabolic rate slows down when you remain in an energy deficit, which is why short periods of calorie surplus can help you avoid fat loss plateaus (while allowing you to enjoy the extra food for a while). This is the point at which you need to assess your progress and make adjustments.

Some people may be able to maintain consistent fat loss for months without ever needing a refeed phase, while for others fat loss may stall after just a few weeks. Since I can't provide a plan that is optimal for everyone, here is just a sample diet plan for a person in this category who is trying to improve their body composition:

  • Phase 1 - Fat loss with the goal of losing roughly 5% weight per month or until weight loss stops. A good starting point to achieve this is to reduce calorie intake by 500 kcal below maintenance calories.
  • Phase 2 Once weight loss has stopped, increase your calorie intake back to your maintenance calorie level for 1 to 2 weeks, or possibly to the point of a slight calorie surplus. You may gain a little weight during this phase - but don't panic.
  • Phase 3 - Continue the weight loss phase as described in phase 1. Repeat phases 1 and 2 until you have reached your target body fat percentage.

Case 2: Fat and no significant amount of muscle mass

If a person lacks muscle mass and is too fat, then there is a dilemma here as energy expenditure is likely to be quite low from the outset and this person will need to reduce their calorie intake significantly in order to lose small amounts of weight. In addition, most of the body mass lost with a large reduction in energy intake in these cases will be muscle mass, so the weight will decrease but the body fat percentage will not. This usually manifests itself in what is called "skinny fat" syndrome, which describes a person who is both thin and flabby at the same time.

Therefore, if you fall into this category, it is generally wise to consider either eating maintenance calories or maintaining a slight calorie deficit and focusing on training with weights.

Most people will probably think it's insane to recommend that an obese/overweight person not focus on weight loss and a ton of cardio training, but I would argue that a focus on building and maintaining reasonable amounts of muscle mass and strength will help that person achieve more efficient fat loss in the longer term at this point. Don't be blinded by short-term results.

Also, keep in mind that I am not saying that these individuals should start a maximum fat loss phase and pretend that this is the best thing for them. If you give yourself time, stay consistent and focus on resistance training, then even a slight calorie deficit (or even the maintenance calorie amount) will be conducive to improving body composition as you slowly shed fat while maintaining strength and muscle mass.

This is not to say that you shouldn't incorporate cardio into your program, just that it's not necessary (or helpful) to do hours of cardio unless you're primarily sacrificing muscle mass (which you already don't have much of to begin with if you fall into this category).

As mentioned above, for people who fall into this category, there is no one-size-fits-all scheme, so here is an example (which is not too different from the one for people in the first category):

  • Phase 1 - Maintain a slight deficit or eat your maintenance calorie intake with the aim of losing a small amount of weight (e.g. 250 to 500 grams per week). A good starting point to achieve this is to stay within your maintenance calorie range. You can also choose to stay a few hundred kcal below your maintenance calorie intake if you are not seeing any visible weight loss.
  • Phase 3 - As in case 1: continue the diet phase as described in phase 1. Repeat phases 1 and 2 until you have reached your target body fat percentage.
  • Phase 2 - Same as phase 1 for the other category: as soon as the fat/weight loss comes to a halt (or you notice a noticeable decrease in your strength), increase your calorie intake back to the maintenance calorie level or possibly above for 1 to 2 weeks. You may gain a little weight during this phase - but don't panic.

In the case of overweight teenagers

The dilemma of being overweight as a teenager can be quite complicated. These individuals usually do more harm than good for their bodies by focusing on extreme calorie restriction. If you're an overweight teenager, here's the hard truth: you need to figure out what made you overweight and change those habits.

Extreme weight loss during crucial stages of development can have devastating effects on your metabolic health and hormonal system. Many overweight teens take their fat loss efforts too far and risk a variety of health problems just to get the weight off the scale.

For this reason, overweight teens are more likely to benefit from the recommendations for Case 2 and should focus on changing their unhealthy eating habits and building strength and muscle mass through resistance training.

What about macronutrient ratios?

Although micromanaging your macronutrient intake down to the last gram can have some value, overweight people need to focus primarily on eating less. Having said that, in the long run, it's probably best for most overweight individuals to focus on a balance of fat, protein and carbohydrates rather than sticking to extreme protocols such as a ketogenic diet.

The reason for this is that a focus on moderate intake of all macronutrients and calorie control not only allows these people more freedom while dieting, but also doesn't restrict them or give them the idea that certain foods are off limits.

Final words

The reason most people don't stick with a plan is because they are far too concerned with short-term results (or lack thereof) and completely forget that improving health, fitness and body composition is a lifelong endeavor. You can't accelerate this process at will - it will take concerted effort and consistency on your part to achieve the body and level of fitness you desire. If at any point you feel like you're not making progress, take a step back, look at your long-term goals and make any necessary changes to your current habits to continue your journey successfully.

You need to understand what has made you overweight and change those habits. Simply doing this and implementing a solid, consistent diet and exercise program will reduce many of the negative health consequences associated with obesity. Don't make this more complicated than it needs to be.


1. Tokunaga C, Yoshino K, Yonezawa K (2004). "mTOR integrates amino acid- and energy-sensing pathways". Biochem Biophys Res Commun 313 (2): 443-6. doi:10.1016/j.bbrc.2003.07.019. PMID 14684182.

2 Wullschleger S, Loewith R, Hall MN (February 2006). "TOR signaling in growth and metabolism". Cell 124 (3): 471-84. doi:10.1016/j.cell.2006.01.016. PMID 16469695.

3 Ruderman NB et. al. Minireview: Malonyl CoA, AMP-activated protein kinase, and adiposity. Endocrinology (2003) 144: 5166-5171.

4 Bolster, DR. AMP-activated protein kinase suppresses protein synthesis in rat skeletal muscle through down-regulated mammalian target of rapomyacin (mTOR) signaling. J Biol Chem (2002) 277: 23977-23980.

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