According to a 2018 review in the Oxford Academic Advances in Nutrition Journal (OAANJ), the answer is yes, you can build muscle and lose fat at the same time, if you do it right. The review looked at numerous studies that analyzed the effects of being in a negative energy balance, and how it affects body composition and muscle growth. Here are the main findings:
1. The Amount of Daily Protein Ingested Is Important:
There is research pointing toward a protein intake of greater than 2 grams per kilogram of body weight per day for those in a caloric deficit, looking to gain/maintain muscle mass, while losing fat in addition to a resistance training program. This number could possibly be even higher for older strength training individuals due to lower levels of protein synthesis associated with age. Compare this to a recent meta-regression of 49 studies surrounding protein intake for optimal muscle gains in a surplus of calories, that showed the greatest increases in muscle mass were obtained using 1.6g per kilogram of body weight per day. This discrepancy between feeding states, illuminates the importance of a higher protein intake during a caloric deficit vs a surplus.
- Avoid an Extreme Calorie Deficit for Muscle Gains
The total number of calories you cut out of your daily intake, can have a significant impact on whether you gain or actually lose muscle tissue over time. According to the OAANJ review, it appears that consuming protein at amounts in excess of the RDA can be beneficial for supporting muscle mass during modest energy deficits, for example less than 40% of total calories. When deficits exist that are higher than 40%, the increases in dietary protein may not lead to greater muscle mass protection. This is especially true in leaner individuals and more advanced trainees.
3. Resistance Training Makes A Big Difference:
Combining resistance training with a higher protein diet during negative energy balance increases the muscle sparing benefits of fat loss. In fact, a 2016 study from McMaster University found that healthy young men actually gained lean mass while dropping fat, in a calorie restrictive diet (40% reduction). This was based on a high intensity, high volume interval training program over six weeks.
- Higher Volume Strength Training is More Important Than Frequency
When focusing primarily on a muscle building strategy, research points to the total volume of work being the most important factor related to increases in muscle size.
According to a 2018 research review from The Journal of Sport Sciences, how many times you hit each muscle group may not matter as much as how much total work you do in the gym. After reviewing 25 studies, the results of the review showed no significant difference between higher and lower frequency workouts-as long as the total volume was equal.
In other words, training your chest once per week vs 3 times per week, would not lead to less muscle size over the long term; if total work completed was equal.
It seems that if you complete 9 sets of work targeting a muscle group, it doesn’t matter if it is 3 sets on three days, or 9 sets on one day, as long as the total volume matches up.
The fact still remains that for optimal gains, if volume is a key factor to bigger muscles (as the research supports), then hitting a higher number of sets on all muscles more frequently than once per week (especially for younger trainees), would result in more sets completed than would be possible in a single session. This could be more beneficial, if muscle size is the goal.
- Don’t Let Short Term Gains Derail Long Term Success
The takeaway point is not to let “optimal” get in the way of “sustainable”. Workout and nutrition science is often in support of better ways to get results in the shorter term, with a blind spot towards human behavior in the long term. The best training and nutrition plan is the one you can most easily maintain over time.