Can you gain muscle whilst losing fat?

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If your goal is to lose as much body fat as you can, as fast as possible, prepare yourself to lose muscle too. The reverse also being true. But how easy is it to gain muscle whilst losing fat? A more accurate way to phrase the question would be “can you gain muscle in a calorie deficit?” The short answer is yes. But it requires some consideration.
This endeavour becomes more straightforward if the trainee fits any of following categories:
– Minimal weight training experience (Demling and DeSanti, 2000)
– Overweight (Hulmi et al., 2017)
– Returning from an injury or training hiatus (Longland et al., 2016).
In a review of key weight loss studies, six out of seven incurred muscle loss. Worth noting, in the 2015 case study by Robinson and Gillibrand almost half (43%) of the weight lost was muscle! Only a single intervention by Garthe et al. (2011) produced any gains in muscle. The more aggressive weight loss strategies incur greater loss of muscle. You can still gain muscle and lose fat at the same time. But there is a limit to the rate of fat loss. Beyond which sacrificing muscle is unavoidable. The generic Dietary Guidelines recommend a calorie deficit of 500 kcal per day. This is regardless of gender or size. Following the success of Garthe et al. (2011), I recommend a weight loss target of 0.5-0.7% bodyweight per week. This could be as low as a 300 kcal deficit for a female client.

Take an individual approach to fat loss and base calorie deficit on a percentage of bodyweight.

How easy is it to build muscle?

Renown physiologist Lyle McDonald developed a model for predicting genetic muscular potential (2009). Gaining muscle becomes painfully slow after the fourth year of serious training. Even in a hyper-caloric state (calorie surplus). In fact, if you managed to gain 3kg of muscle in your third year that would be considered a success! Question anyone with years of training experience that announces that they are going to gain 7kg of muscle in only a few weeks. They would need world-class genetics. Or supra-physiological doses of anabolic hormones. With neither being the case, the harsh reality would be that most of the weight gained would be fat. (Unfortunately) we are all bound by the laws of human physiology.

Measuring muscle and fat

How do we gauge the success of our training and nutrition plan? Let’s talk about body composition: the measurement of muscle and fat. Ulijasze et al. (1999) describe a hierarchy in the precision of different anthropometric measures. Weight is the most accurate. Yet the weighing scales have received a bad press lately. If you believe what you read, weight no longer seems to be a valid measurement. You step on the scales and the number remains the same. What happened?
– You cancelled out all fat loss by gaining exactly the same amount of muscle. Unlikely. The alternative is you didn’t lose any fat. You’re not in a weekly calorie deficit. You have no idea of your calorie intake. You’re over-consuming calories at the weekend.
– Or your non-exercise activity (NEAT) has reduced to compensate for any training you do.
Circumference measurements show significant inter-observer discrepancies. Different personal trainers would measure different results for the same client! Thus, results are not without controversy. However, when supported by weight measurements, this is still my preferred choice. Skin-fold measurements are even more unreliable due to the high-risk of human error. Their accuracy is wholly dependent upon the skill of the operator. It should be the preserve of experienced physiologists who use callipers daily. Not unskilled personal trainers who use them a couple of times a week, at best. The gold standard in body composition assessment is Dual-Energy X-ray Absorptiometry (DEXA). The DEXA uses X-rays to measure muscle, fat and bone to the nearest hundredth of a gram. Assessment is both quick and precise. At the end of this article are the DEXA scans from my MSc case study. My client returned from a break in exercise to training with me three times a week. He gained 5kg of (lean) muscle whilst his body fat dropped to 8.1%.
Image of Liverpool Street personal trainer Jason Jackson using a DEXA scan to measure muscle and body fat

Image of Liverpool Street personal trainer Jason Jackson using a DEXA scan to measure muscle and body fat


Protein intake is often overestimated in overweight individuals. Their muscle mass contributes to a much lower percentage of their total body weight. And in turn, underestimated in leaner individuals. Thus, athletes are at greater risk of losing muscle during caloric restriction. Protein recommendations are for the “general population”. Individuals with an average-to-high body fat percentage. In an ideal scenario, muscle mass (instead of total body weight) would guide recommendations for leaner trainees. Unfortunately, this information is only readily available with DEXA scans.

Start with 2g of protein per kg of bodyweight. This should be further increased in leaner individuals.


To gain muscle, you need to increase the total volume of work done within each training session. This requires more reps per set, more sets per exercise and reduced rest intervals. The much-maligned carbohydrate is essential to fuel this increased workload. An excessive reduction in carbohydrate would result in reduced muscle glycogen levels. This would impair performance, and the ability to gain muscle. As demonstrated in the study by Walberg et al. (1988).

Training to build muscle

Despite the PT sales pitch, fat loss is achievable through calorie restriction alone. Whereas resistance training drives muscle growth when supported by sufficient protein intake. If your progress has stalled you need a novel training stimulus. For many, this could be working with an experienced personal trainer. Fine-tune your lifting technique. Focus on tempo. Contract the muscle forcibly each rep. And adapt to progressively shorter rest periods. You should follow a periodised training and nutrition strategy. Progress will dictate reps, rest, macronutrients, intake and expenditure.

Training volume

The International Journal of Sports Medicine published a review of 60 studies into building muscle. Wernbom et al. (2007) examined the effects of training volume and frequency. The Swedish researchers found that <70 reps per muscle group per session was the optimal number for muscle growth. Increasing volume is the key determinant of building muscle. But, there is an “inverted U” response to training volume (Helms et al., 2014). Beyond the “sweet-spot”, too much in a single session can be detrimental to muscle development. Caveat: some individuals are able to tolerate more volume, dependant on their training age or genetics. 

Training frequency

So gone are the old-school bodybuilder-style training splits. “Chest day” is a thing of the past. Schoenfeld et al. published a study last year investigating the impact of training frequency. When total weekly volume was the same, training each muscle group twice per week was superior for muscle gains. Thus, I always recommend clients train with their personal trainer twice per week. Once isn’t enough. I recommend separate push, pull and lower body sessions, repeated twice per week. Muscle groups will then be exposed to a higher frequency of training stimulus. Enhance recovery by dividing training volume over multiple days.

Muscle activation is the key to gains. Further evidence to work with an educated personal trainer comes from Snyder et al. (2009). Coaching cues should include stabilisation, contraction, joint angle, range of movement and tempo. The Americans used EMG activity to measure response:

Muscle activation increased by 17.6% when participants performed exercises after expert training (Snyder et al., 2009) 

– >2g protein per kg of bodyweight
– 40-70 reps per muscle group per session (Wernbom et al., 2007)
– Train each muscle group twice per week (Schoenfeld et al., 2016)
Image of DEXA scan results from Jason Jackson's MSc case study showing muscle, fat and bone density

Image of DEXA scan results from Jason Jackson’s MSc case study showing muscle, fat and bone density


Demling, R. H., & DeSanti, L. (2000, February). Effect of a Hypocaloric Diet, Increased Protein Intake and Resistance Training on Lean Mass Gains and Fat Mass Loss in Overweight Police Officers. Annals of nutrition & metabolism, 44(1), 21-29.
Häkkinen, K. and Kallinen, M., 1994. Distribution of strength training volume into one or two daily sessions and neuromuscular adaptations in female athletes. Electromyography and clinical neurophysiology, 34(2), pp.117-124.
Hartman, M.J., Clark, B., Bemben, D.A., Kilgore, J.L. and Bemben, M.G., 2007. Comparisons between twice-daily and once-daily training sessions in male weight lifters. International journal of sports physiology and performance, 2(2), pp.159-169.
Helms, E.R., Fitschen, P.J., Aragon, A.A., Cronin, J. and Schoenfeld, B.J., 2015. Recommendations for natural bodybuilding contest preparation: resistance and cardiovascular training. J Sports Med Phys Fitness, 55(3), pp.164-78.
Hulmi, J. J., Isola, V., Suonpää, M., Järvinen, N., Kokkonen, M., Wennerström, A., & Nyman, K. (2017). The effects of intensive weight reduction on body composition and serum hormones in female fitness competitors. Frontiers in Physiology, 1-16.
Garthe, I. G., Raastad, T., Refsnes, P. E., Koivisto, A., Sundgot-Borgen, J. (2011). Effect of Two Different Weight-Loss Rates on Body Composition and Strength and Power-Related Performance in Elite Athletes. International Journal of Sport Nutrition & Exercise Metabolism, 21, 97-104.
Longland, T. M., Oikawa, S. Y., Mitchell, C. J., DeVries, M. C., & 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. American Journal of Clinical Nutrition, 103(3), 738-746.
Robinson, S.L., Lambeth-Mansell, A., Gillibrand, G., Smith-Ryan, A. and Bannock, L., 2015. A nutrition and conditioning intervention for natural bodybuilding contest preparation: case study. Journal of the International Society of Sports Nutrition, 12(1), p.1.
Schoenfeld, B., Ogborn, D. and Krieger, J. (2016) ‘Effects of Resistance Training Frequency on Measures of Muscle Hypertrophy: A Systematic Review and Meta-Analysis’. Sports Medicine, 46 (11), 1689-1697. doi: 10.1007/s40279-016-0543-8
Snyder, B.J. and Leech, J.R., 2009. Voluntary increase in latissimus dorsi muscle activity during the lat pull-down following expert instruction. The Journal of Strength & Conditioning Research, 23(8), pp.2204-2209.
Ulijaszek, S.J. and Kerr, D.A., 1999. Anthropometric measurement error and the assessment of nutritional status. British Journal of Nutrition, 82(03), pp.165-177.
Walberg, J.L., Leidy, M.K., Sturgill, D.J., Hinkle, D.E., Ritchey, S.J. and Sebolt, D.R., 1988. Macronutrient content of a hypoenergy diet affects nitrogen retention and muscle function in weight lifters. International Journal of Sports Medicine, 9(04), pp.261-266.
Wernbom, M., Augustsson, J. and Thomeé, R., 2007. The influence of frequency, intensity, volume and mode of strength training on whole muscle cross-sectional area in humans. Sports medicine, 37(3), pp.225-264.
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