Often we see people looking to add mass whilst holding relatively high amounts of body fat.

This is always a bad idea, so we though we would take some time to explain and use a few references which you can check, to understand why one should get lean (10-12% body fat before looking at add mass) and then stopping bulking when body fat is arond 15% and doing another mini cut.


Practical Recommendations

Ok, enough theory crap. Based on the above data, here’s what we would generally recommend to bodybuilders or athletes who want to put on muscle mass (i.e. nearly all of them).

  1. If you’re above 15% body fat (about 24-27% for women), diet first. If you can get to the 10-12% (19-24%) body fat range or so, I think you’ll be in an overall better position to gain mass. Trying to get super lean will probably end up screwing you in the long run because your body will be primed to put back fat on (and most other physiological systems are screwed up as well) when you get super lean.
  2. After finishing your diet, regardless of how lean you get, take 2 weeks to eat at roughly maintenance calorie levels before starting your mass gaining phase. The reason has to do with the physiological adaptations to dieting described briefly above. Although you can’t reverse all of them short of getting fat again (or fixing the problem pharmaceutically), 2 weeks at maintenance, which by definition should be higher calories than you were eating on your diet, will help to normalize some of them. Leptin, thyroid, SNS output should improve a bit, along with other hormones, putting you in a better place to gain mass without super excessive fat gain. Make sure to get at least 100 grams of carbs/day or more during this phase so that thyroid will come back up.
  3. Only try to add mass/bulk until you hit the top end body fat percentage listed in #1 above. So that’s about 15% body fat for men and 24-27% body fat for women. What this would mean in practice is that you diet to 10-12% body fat for men (22-24% for women), eat at maintenance for two weeks to try and normalize things, and then add mass until you hit 15% body fat for men (22-24% for women) and then diet back down. Over a number of cycles, you should be able to increase your muscle mass while keeping body fat under control

Don’t get too lean!

In the starvation study (the Minnesota Semi-Starvation study) men were dieted for 6 solid months reaching 4-5% body fat at the end of the study. Then they were refed and body composition was tracked. By the theory being advocated, they should have gained lots of LBM and little fat during refeeding, they were clearly super lean to start out with. But this is absolutely not what happened.

As would be expected by some who understand the body and based on the metabolic adaptations to dieting, their bodies were mainly primed to replenish fat stores. Reductions in metabolic rate, fat oxidation and thermogenesis all contributed to a preferential gain of body fat and these systems didn’t reset themselves until all of the body fat lost had been regained (see study 8). Quite in fact, signals from body fat (i.e. leptin and the rest) are the mechanism behind this physiology (see study 9).

The bottom line is that, in dieted down individuals, the body is primed to gain body fat at the expense of LBM to replenish what was lost during the diet. Again, this is fundamentally different than looking at genetically lean individuals (for whom a low body fat percentage is their normal level) in terms of what happens when they are overfed.

What to do?
Gently gain a few more pounds of body fat to get your body ready to add some lean mass by slowly returning over a couple of weeks to get your body back to the maintenance – firing too hard too quick can risk large amounts of fatty deposits, not what you need at this point.

Summing up:

So there you have it, a look at the impact of initial body fat and how it impacts on changes in body composition. Contrary to current (mis) interpretations of the literature, individuals who have dieted down to low body fat levels don’t magically put on lots of LBM when they gain. Quite in fact, if anything, the opposite is true. After an extended diet, the body is primed for fat gain.

However, that doesn’t mean that dieting prior to a mass-gaining phase is a bad idea and getting reasonbly lean prior to ‘bulking’ is probably the best strategy for the average natural bodybuilder.


  1. McClave SA, Snider HL. Dissecting the energy needs of the body. Curr Opin Clin Nutr Metab Care. 2001 Mar;4(2):143-7.
  2. Forbes GB. Body fat content influences the body composition response to nutrition and exercise. Ann N Y Acad Sci. (2000) 904:359-65.
  3. Bray GA. GENETICSS hypothesis of nutrient partitioning. Progress in Obesity Research:7 (1996) 43-48.
  4. Dulloo AG, Jacquet J. The control of partitioning between protein and fat during human starvation: its internal determinants and biological significance. Br J Nutr. (1999) 82:339-56.
  5. Dulloo AG. Partitioning between protein and fat during starvation and refeeding: is the assumption of intra-individual constancy of P-ratio valid? Br J Nutr. 1998 Jan;79(1):107-13
  6. Weyer C et. al. Changes in energy metabolism in response to 48 h of overfeeding and fasting in Caucasians and Pima Indians. Int J Obes Relat Metab Disord. 2001 May;25(5):593-600.
  7. Levine JA. Role of nonexercise activity thermogenesis in resistance to fat gain in humans. Science. 1999 Jan 8;283(5399):212-4.
  8. Dulloo AG et. al. Autoregulation of body composition during weight recovery in human: the Minnesota Experiment revisited. nt J Obes Relat Metab Disord. 1996 May;20(5):393-405.
  9. Dulloo AG, Jacquet J. Adaptive reduction in basal metabolic rate in response to food deprivation in humans: a role for feedback signals from fat stores. Am J Clin Nutr. 1998 Sep;68(3):599-606.Post inspired by Lyle McDonald.