Energy Deficits and Lean Mass and Strength Gains: Can You Add Muscle and Lose Fat At The Same Time?
Posted by: Chip
Key Message: Energy deficits impaired lean mass muscle gains, but the impairment was less on strength gains. There are limited cases where lean mass gains could occur in an energy deficit.
Study: Murphy C, Koehler K. “Energy deficiency impairs resistance training gains in lean mass but not strength: A meta-analysis and meta-regression.” Scandinavian Journal of Medicine & Science In Sports. 2021 Oct 8. doi: 10.1111/sms.14075. https://pubmed.ncbi.nlm.nih.gov/34623696/
This is a new meta analysis of research looking into the effects of an energy deficit on lean mass and strength gains. Traditionally, to lose body fat, the guidance is to get into an energy deficit via exercise and/or a caloric deficit. Conversely, to add muscle, lifters are traditionally coached to be in an energy surplus.
Not surprisingly, the analysis found that energy deficits led to significantly smaller gains in lean mass. The bigger the caloric deficit, the smaller the gains became. Energy deficits led to smaller strength gains, but the effect was less than seen with respect to lean mass gains impacts.
Of course, most hard training gym goers want the “holy grail” of adding muscle and losing fat (i.e. "re-comp"). For some people that may be possible…for others, not so much. The ability to do so involves a couple of factors:
- Your “training age”: If you are a newbie to lifting and relatively “untrained,” your training age is young…if you have been lifting for years and not untrained, you have an advanced training age. Lean muscle gains is often indirectly related to training age, i.e. everything being equal, newbies will often see greater lean gains than someone who has been training for many years.
- Your level of leanness: If you are already extremely lean, your ability to add lean mass will be really limited, i.e. it’s hard to be ripped and be adding a bunch of muscle. People who are obese or skinny fat, however, may be able to gain muscle and burn fat.
So, if you are relatively untrained and have a lot of body fat to lose, you have a good chance at being able to lose body fat and gain lean mass in an energy deficit (provided it is not too large of a deficit). If you are lean and very experienced at lifting, your chance at being able to both at the same time is much smaller.
Other scenarios where a re-comp may be possible: people who are de-trained (used to train and haven't in a long time) and people who have been training sub-optimally (not intense enough, not enough recovery, etc.). If you have been training optimally, your odds at a re-comp are less.
As discussed at our recent Legends Fit seminar for new physique competitors, for fat loss, a good rate of loss is around 0.5% per week. Other studies1 have shown a higher rate of loss resulted in less retention of muscle while cutting. Note as well that metabolic rate varies across individuals in terms of what would be maintenance calories to determine a deficit. Metabolic rate primarily is proportional to fat-free mass (as such women, people 60+ tend to have slightly lower metabolisms)2.
1Rossow, LM, Fukuda, DH, Fahs, CA, Loenneke, JP, and Stout, JR. “Natural bodybuilding competition preparation and recovery: a 12-month case study.” The International Journal of Sports Physiology and Performance. 8:582-592, 2013.
2Pontzer H, et al. “Daily energy expenditure through the human life course.” Science. 2021 Aug 13;373(6556):808-812.
