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Calories - Muscle Growth and Fat loss

Welcome to another blog post Monday!

Today’s topic is Calories - what do YOU need to know? Well, that entirely depends on your goal. Is your goal muscle building? Weight-loss? Or just maintenance? Let’s find out what is important for each of these!

For the people that have been in this industry for a while, you may have heard bodybuilders eating 6000+ calories per day in order to build the muscle they have, and while this is true, it is a bit of a backwards and expensive approach. I’ve always wondered why they would want to spend extra time on the treadmill at the end of their “bulking season” just to cut back the fat they gained from consuming far too many calories. You’re probably wondering what I mean. Well, in order to lose weight, you need a calorie deficit, and in order to gain weight you need a calorie surplus, but just how much is that?

It’s not just as simple as adding in calories. In order to more accurately determine how many calories a person needs in order to gain lean mass effectively, we first need to establish a baseline. That incorporates measuring their Basal Metabolic Rate (which we discussed in our previous article - How Dieting Stops You From Losing Weight) and we also need to establish their current lean body mass (which remember, the more muscle you have the more calories your body will need to survive at rest, muscle uses energy, fat does not)

It is entirely possible to increase your daily calories by 5-10% in order to promote lean muscle growth. For example, if your body requires 2000 calories per day increasing that by 100-200 calories will result in weight gain. However, unfortunately it doesn’t stop here. Daily activity plays a role, some days you may be more active than others, some days you may train harder than others. In addition to this, your starting body composition also plays a role.

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The more detrained a person is, the quicker and easier it is for that person to gain muscle mass.(1) This is due to what is known as “training age.” Training age is all of the contractions a client has accumulated over time relative to their maximal physical potential. The longer we train a specific contraction, the harder it is to achieve change. In order to continue progressing, you need to manipulate variables to elicit growth.

In addition, multiple research papers suggest that naturally lean people with low body fat percentage are more likely to gain muscle than body fat when consuming a larger calorie surplus.(2, 3, 4) In contrast, people with a higher body fat percentage may end up with an increase in fat mass. It would be a good recommendation for this population of people to cut first instead of trying to eat a calorie surplus.

This leads to the second part of todays topic. Calories for weight loss. You’ve all heard the calories in vs calories out and the larger the calorie deficit the “faster” the weight loss. Well, if you’ve been following along and reading my previous blog posts, you will have learned that weight loss is not as simple as dropping your daily calorie consumption to 1000 calories per day (or in some instances fewer!) In fact, in the same way we can build lean mass by increasing our calories by 5-10%, the opposite is applicable, if we reduce our calories by the same 5-10% we can and will lose weight.

In order for this to be optimal, it is important to note that similarly to muscle building, the same factors are at play. What is the persons body composition to start? How much do they weigh? (Yes I know I have said fat doesn’t require calories to move, BUT mass does) If we can assume a persons daily caloric needs are 2000kcal, if we reduce this to 1800kcal, that person will lose weight. (EVEN WITHOUT EXERCISE). The process will be slow but it is possible. However, this is not advice I would give many people looking for longevity in their weight-loss journey. That is because, not only will the body quickly adapt to the change in calorie deficit and 1800kcal become the new normal, BUT the person may experience muscle atrophy, which is the last thing anyone should want! More muscle = less fat. Resistance training and dieting is the only way to maintain the lean mass one currently has.

Tying all of this together, I frequently get asked about (or told) muscle building while in a calorie deficit. The answer is yes, however, it is not easy. Imagine trying to build a house in the middle of a hurricane. Muscle building is the house and the hurricane is the calorie deficit. However, it’s not as straight forward as this.

Body Recomposition

Muscle growth is the creation of new muscle proteins added to muscle cells. The result, bigger and larger muscles. This is known as muscle protein synthesis. In order to achieve this we must strength train and consume protein and calories.

Muscle protein synthesis is impacted by a number of things, such as; inactivity, inadequate protein and calorie consumption, lack of sleep. More important to note, is that these factors actually increase muscle protein breakdown, the opposite of what we are looking to achieve.

Our previous article on “Muscle Building 101” talks about progressive overload, covering the importance of resistance training for building muscle.

As we’ve previously discussed, the most important time for muscle building is the first 6 to 12 months of resistance training. After this (and to some extent during) you will be able to burn fat far quicker than you can build muscle.

So how does body recomposition work optimally?

Well, as we’ve discussed, our bodies require sufficient energy and macronutrients in order to build muscle, however, that energy doesn’t necessarily have to come from food. Interestingly, it is possible you have plenty of calories in the form of stored fat in order to provide enough energy to build muscle.

For example, I am roughly around 10% body fat and weigh 210 lbs. Safe body fat levels for men are above 4% which leaves me 6% of body fat energy to use, in this instance 12.6 lbs. You’ve probably heard before that 1 lb of fat is equivalent to 3500 calories, which means I have approximately 44,000 calories of body fat that I can use to build muscle.

While this sounds great on paper, it doesn’t take in to account how our body adapts to caloric restriction. When you restrict calories, the body reprioritizes other energy intensive processes like muscle growth. So regardless of how much stored energy I have, the body is recognizing my calorie restriction as “starvation.” As a result hormone levels lower, protein breakdown rises, protein synthesis decreases and therefore maintaining the muscle mass is more challenging, let alone gaining.

The larger your calorie deficit, the faster you lose fat yes, BUT the more your protein balance decreases. Ultimately, the process of building muscle at the same time as losing fat is an incredibly slow process.

As I mentioned previously, the rate at which you lose fat is far quicker than building muscle. Men and women can lose roughly 1 to 2 lbs of fat per week without losing muscle. Muscle building is significantly less at around 0.5 lbs of muscle per week for men (in the first year of lifting AND a calorie surplus), following year one this number halves and for women, these numbers can be halved again. Furthermore, if you’re restricting calories, you can expect to gain even less muscle than this.

To conclude, while it is not impossible to build muscle while losing fat, it is an incredibly slow process and far more challenging to actually accomplish in reality versus on paper. This doesn’t mean give up on this journey, it just means you need to lower your expectations and be patient.

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