Dr. Chad Kerksick: Should You Lose Weight Before Building Muscle?

Dr. Chad Kerksick: Should You Lose Weight Before Building Muscle?

This question gets posed quite a bit as it is commonly discussed and thought that you can’t gain muscle and lose fat at the same time.

Much of this thought likely comes from the bodybuilding world where these individuals would go through a “bulk” phase where they trained with high volumes and ramped up their calorie intake to help lay down as much mass (both muscle and fat) as possible. Depending on the bodybuilder and their preferences, a healthy dose of pharmaceutical assistance was likely provided as well.

You can also see this mindset come to life with certain types of athletes or sports where more size may be beneficial for performance at a certain sport or position (such as baseball, rugby, or football).

I remember back in college during the Winter/Spring training season for the football team if there was a guy who was under-sized or were told they were switching positions and they needed to “size up” they would be on the “gain mass at all cost” plan.

For the majority of time with the athletes, the goal was to increase their body mass, so once they reached their body mass goal ... they would dial back this approach and focus on athletic development.

The bodybuilders, on the other hand, would pivot their approach once they gained the size they wanted, and start to “cut” and attempt to lose as much fat as possible.

This approach has worked for years, but the problem many times is that mass is gained much too quickly. This means that a decent amount of fat was gained along with muscle, and when they cut, a decent amount of muscle was lost when the “cutting” phase commenced.

In modern day, however, a blueprint has been emerged in the scientific literature where someone doesn’t really need to think about doing the “gain muscle” and “lose fat” phase sequentially. Instead, they can be done consecutively.

Just gain muscle and lose fat at the same time. It sounds easy, right? It isn’t.

So my answer to the question, “Should I lose weight before building muscle?" is “No, you should do both at the same time”. OK, great, but how?

I did say there was a blueprint and it’s a blueprint of some guiding recommendations. Here it goes…

Recommendation #1 – Be Patient. Slow Down the Rate of Weight Loss

Spread out or lengthen the timeline upon which you want to achieve the goal. Several sources of scientific data can be referenced to reinforce the notion that slowing the rate at which you expect to transform your body from flabby to chiseled.

In fact, a rate of weight loss has even been recommended for competitive athletes who also hope to maintain or even improve their strength and power. The guideline is to lose no more than 0.7% of your body mass per week.

This recommendation comes from a study which compared a ‘fast’ (1.4% body mass per week) to a ‘slow’ (0.7% body mass per week) rate of body mass loss per week (Garthe et al. 2011, 1).

This study guided 24 high-level competitive athletes through two different dietary plans that delivered different amounts of calories and macronutrients to achieve a weight loss rate of either 0.7% body mass per week or 1.4% body mass per week.

The athletes were randomly assigned to the two different dietary approaches and completed all of their normal athletic training activities each week.

Before and after following their assigned diet, the athletes had their body mass, body composition (fat mass, lean mass, etc.), speed (40-m sprint), lower-body power (vertical jumps on force plates), and strength (one-repetition maximum) measured.

To achieve the prescribed weight loss, the group who followed the “fast weight loss” restricted their energy intake by approximately 30 ± 4% while the “slow weight loss” reduced their calorie intake by 19 ± 2%.

Both groups lost similar amounts of body mass and fat mass, while lean body mass increased by 2.1% in the slow weight loss group ... and the fast weight loss group did not gain any lean mass.

Additionally, the slow weight loss group gained significantly greater amounts of upper body strength, lower body strength, and lower body power with the differences being statistically different for upper body strength.

(Garthe et al. 2011)

Speed of weight loss is a critical factor to help leverage as much of your weight loss towards fat loss as possible. The reason for this is largely thought to be the magnitude of calorie restriction that is needed to achieve a fast and a slow rate of weight loss.

In reviewing this table, one will quickly see that for a faster rate of weight loss to occur, much steeper reductions of calorie intake are needed to achieve the faster rate of weight loss, but it has its consequences in terms of what type of weight is being lost and how much performance is being impacted.

(Garthe et al. 2011) Slow Weight Loss Fast Weight Loss
 Energy Intake
-469 ± 61 -791 ± 113
Lean Mass
1.0 ± 0.2 -0.3 ± 0.4
Fat Mass
-4.9 ± 0.7 -3.2 ± 0.5
Vertical Jump
2.0 ± 0.7 0.3 ± 0.8
1RM Bench Press
7.5 ± 0.5 2.3 ± 1.7
1RM Bench Pull
5.8 ± 1.5 1.8 ± 1.7
1RM Squat
9.0 ± 2.1 7.0 ± 1.7

So where does this leave us? The faster you want to lose weight, the deeper a calorie deficit you need to create, which results in more lean tissue being lost (or not gained altogether) and many aspects of performance being negatively impacted. Moreover, this doesn’t even begin to touch how much more hunger you’ll feel, how much less fuel you'll have for recovery, an increased likelihood of getting sick, and more.

Many people at this point then ask the question, “How much of a calorie deficit is good or should I try to achieve?”

(Garthe et al. 2011)

First, there is no consistent answer from one person to the next for a variety of reasons, but a review paper on studies that looked at the relationship between calorie deficit and lean tissue loss provides some insight.

A figure is provided below that helps to build a larger picture over the impact greater energy deficits on lean mass changes. As you can see, the separation point between yellow and green sits right around 400 kcals/day and the difference between yellow and red is approximately 650-700 kcals/day.

What works really well, in this instance, is if you look at the range of calorie deficit achieved in the table. This somewhat aligns with the yellow region on the figure.

Then, consider the magnitude of differences from end of the yellow region to the other in terms of performance changes and body composition changes. The take-home message is simple: if you drive too hard of a line and create a steep calorie deficit, you are going to lose more lean tissue and the performance gains you will achieve will be blunted.

Recommendation #2 – Include Exercise and Make It Resistance-Based

That first recommendation is a big one and largely drives the entire conversation. At the highest most basic level, the next recommendation is for people to include exercise.

Studies have told us that include any form of regular exercise will do two great things.

First, it will promote positive changes in one’s health. Examples include reductions in blood pressure, reductions in lipids like triglycerides and cholesterol, reductions in glucose and insulin, and increases in bone strength, mental health and cognition, and increases in muscle health.

The second thing adding exercise will do is that it will help to leverage as much of the weight loss as fat loss.

This is an important point to consider because I will over and over that people do not want to lose weight, but rather they want to lose as much fat as they can and retain (or even gain) as much muscle as possible.

This is where exercise becomes so valuable because getting regular exercise helps to provide a stimulus that signals your body to hold on to muscle.

A key point for everyone reading is that at this point in the recommendation, do not get caught up in what type of exercise or worrying about choosing the “correct” or “best” form of exercise.

Many different forms of exercise are excellent at achieving this outcome and the suggestion is to do more walking, jogging, swimming, group fitness classes, resistance training, etc.

Beyond just picking any type of exercise, even greater body composition outcomes can be achieved if someone regularly performs resistance exercise in combination with their dietary program.

While all forms of exercise will aid in maintaining a healthy weight, blood pressure, cholesterol and glucose changes, adding resistance training to a diet that provides a calorie deficit will absolutely help your body lose as much fat as possible while reducing the amount of lean or muscle tissue you lose.

This research is not developed enough to provide a recommendations as to how much resistance training you should do and if a certain number of sets and repetitions, etc. are better than others. So my resistance training recommendation is very generic.

Each person should at a minimum do 2-3 days per week of resistance exercise. For each of those workouts, one should choose 1-2 exercises that target every major muscle group in your body (chest, shoulders, back, abs, lower back, biceps, triceps, quads, glutes, hamstrings, calves) and perform 2-3 sets of 10-12 repetitions with a load that makes the last 1-2 repetitions challenging to complete.

Do not overthink this. Just add resistance training! Don’t over-engineer it and think that more complicated exercises or sets and reps are better.

For our purposes in this article, no data suggests that one form, style, or type of resistance training is better than the other, so don’t spend anytime bantering over what is best. Just develop a routine, work hard, and be sure to use loads that are challenging for you to complete the movement for the last 1-2 repetitions.

Recommendation #3 – Get Enough Protein

This is the final step in the equation. First, a few points should be highlighted regarding protein and how it fits into this discussion.

Key Point #1 is that people must understand that our bodies don’t really care about our physique and it ultimately cares about survival.

Key Point #2 is that human have a daily ongoing need for protein. We don’t store protein like we store carbohydrates and fat. If our body has a need for protein, it finds it.

Key Point #3 is that research continually provides evidence that exercising people may need more protein and in certain scenarios (such as energy restriction) our daily protein needs likely goes up.

These key points help highlight one of the biggest problems that occurs when someone starts cutting eating less food. Put simply, because of their desire to lose weight, they cut calories, which is oftentimes the most impactful way to create a calorie deficit.

As food consumption goes down, one’s consumption of carbohydrates, fats, and protein often go down. As deeper and deeper calorie cuts are made, the lower one’s protein intake gets.

Many times people begin consuming less protein than what their body needs to maintain life (remember key point 1) and because there is continual daily turnover (remember key point 2), this protein deficit let’s call it continues from one day to the next.

As a result, people who are dieting and not aware of their daily intake can easily consume too little protein to meet their body’s daily needs and when that occurs the body will be forced to break down existing sources of amino acids to meet the daily turnover requirement.

This is where key point 3 becomes important. Much research in the past 20 years has continually illustrated favorable outcomes in people who are dieting that consuming a diet with increased amounts of protein can help achieve more weight loss, improve various health markers such as triglycerides, cholesterol, and glucose, and also help stimulate greater improvements in body composition (i.e, lose more body fat).

I can think of two studies that really nicely illustrate this point. The first study was published by researchers at the University of Illinois (Layman et al. 2005, 3) and conducted in a large group of overweight-obese men and women and had them exercise while follow reduced-calorie diets with more carbohydrate or more protein.

When people consumed more protein, their weight loss was better, their health markers improved, and they lost more body fat. When they added an exercise program to the diet, their results were even more impressive.

Another study published by researchers form McMaster University in Canada (Longland et al. 2016, 2) had overweight men reduce their calories by 40% and then follow an exercise program where they completed a 6-day pattern of resistance training, high-intensity intervals, plyometric work, and some cardiovascular training.

The control group consumed 1.2 g/kg/day of protein in their reduced calorie diet while another group consumed 2.4 g/kg/day of protein. They followed this pattern for one month.

As seen in the figure below, both groups lost similar amounts of weight in one month (approximately 3.2-3.3 kgs), but when you look at the composition of weight that was left (how much fat and how much lean tissue), a different story is told.

In both scenarios the group that consumed a higher protein intake did noticeably better with the higher protein group gaining over 1 kg of lean tissue while the lower protein group didn’t gain any lean tissue.

For fat, the higher protein group lost right at 5 kg of fat mass while the lower protein group lost around 3.4 kg of fat. These results nicely highlight the power of consuming a diet higher in protein while restricting calorie intake at losing fat and gaining lean (muscle) tissue.

Finally, how much protein is enough? This study said better results happened with 2.4 g/kg/day and many recommendations suggest levels starting at 1.6 g/kg/day (which happens to be 2x the RDA) up to 2.0 g/kg/day. For those of you that don’t like kilograms, this equates to a protein intake that gets pretty close to 1 gram of protein per pound.

One final point must be mentioned about this study because many people will focus on the results of the higher protein group, but look at the overall power and effectiveness of restricting energy intake and following an intense exercise program in just four weeks!

Don’t overlook or under-appreciate the power of cutting calories and exercise together.

In closing, I don’t think people build muscle first and then lose weight (or vice versa), I think you should to achieve both at the same time. This article lays out a evidence-based blueprint of how this can be done with the first step being to slow down the speed at which you want to lose weight.

The second step is to add resistance training and the third step is to make sure you are getting enough protein.


(1) Garthe, I., Raastad, T., Refsnes, P.E., Koivisto, A., and Sundgot-Borgen, J. (2011). Effect of two different weight-loss rates on body composition and strength and power-related performance in elite athletes. Int J Sport Nutr Exerc Metab 21, 97-104.

(2) Longland, T.M., Oikawa, S.Y., Mitchell, C.J., Devries, M.C., and Phillips, S.M. (2016). Higher compared with lower dietary protein during an energy deficit combined with intense exercise promotes greater lean mass gain and fat mass loss: a randomized trial. Am J Clin Nutr 103, 738-746. 10.3945/ajcn.115.119339.

(3) Layman, D.K., Evans, E., Baum, J.I., Seyler, J., Erickson, D.J., and Boileau, R.A. (2005). Dietary protein and exercise have additive effects on body composition during weight loss in adult women. J Nutr 135, 1903-1910. 135/8/1903 [pii].