Should Strength Athletes do Bulk and Cut Cycles?
Only have a second? Check out the takeaway below. Have 5 minutes? Check out the rest of the newsletter.
TRAINING TAKEAWAY: Body recomposition - simultaneously losing fat and gaining muscle - is possible, even in trained lifters. However, most strength athletes are unlikely to maximize long-term body composition improvements with this approach and would maximize strength with bulking and cutting cycles. Further, there are individual differences in the optimal approach to long-term bodyweight manipulations.
The Problem
Strength athletes don’t put much thought into long-term bodyweight manipulations. This is a problem, and it often holds back lifters.
Practically, the question I’ll be exploring is this: Over 3 years, which approach will lead to the best strength performance?
A) Body weight maintenance
B) Three separate cycles of a 10-month bulk followed by a 2-month cut, with the same ending body weight as scenario A
Background
Muscle growth is an energy-intensive process. Although this energy cost hasn’t been precisely quantified in the research, estimates are ~2500-3000 calories per lb of muscle accrued. This includes the energy content of the new muscle tissue, the energy cost of synthesizing this muscle tissue, and other energy requirements from having more metabolically active tissue.
With this in mind, energy balance can be manipulated by bulking and cutting cycles. The idea is that bulks allow for an energy surplus in which muscle growth is more efficient. Since this comes with fat gain, cuts are used to reduce body fat and “set up” the next bulking phase.
I’ve anecdotally observed that this bulk/cut approach isn’t the default approach for strength athletes. I suspect this is due to the recent popularity in 1) the idea that muscle growth doesn’t contribute to strength and 2) the idea that body recomposition (simultaneous muscle gain and fat loss) can occur even in trained individuals.
I won’t discuss #1 in-depth in this newsletter, but I’m operating under the premise that body composition improvements not only contribute to strength gains but may also be the best predictor of long-term strength.
The rest of this newsletter will be most relevant to #2.
Body Recomposition
Thinking back to the proposed question, body composition improvements in scenario A require body recomposition (simultaneous muscle gain and fat loss).
As mentioned, energy is required to gain muscle. In the absence of an energy surplus, energy can be obtained from endogenous stores (body fat) and thus an energy surplus is not required to gain muscle.
This helps explain how body recomposition can occur. Indeed, simultaneous muscle gain and fat loss is reported in the research. While this is most common in untrained participants, body recomposition is observed in multiple studies with trained participants. I gathered the studies from a recent review that A) had trained individuals, B) observed statistically significant increases in fat free mass, and C) observed statistically significant decreases in fat mass. For the columns reporting changes in fat free mass and fat mass, I only included data from groups that experienced body recomposition. For example, if group A experienced body recomposition but group B did not, group A’s data is below.
As we can see, 7 studies fit the criteria. Based on relative squat strength, I’d argue that the training status in 4 of 7 of these studies indicates only a recreational training status. Nonetheless, this is certainly a proof of concept that body recomposition can occur in trained individuals.
However, I’m most interested in whether this is a more or less effective long-term strategy compared to bulk/cut cycles.
How Helpful is an Energy Surplus for Muscle Growth?
One approach to answering this question is to determine whether body recomposition is or isn’t the norm in the research. However, this approach can’t necessarily indicate the superior approach. In studies not reporting body recomposition, one could argue that the energy surplus was too large and inhibited fat loss. In studies that do report body recomposition, one could argue that muscle growth would have been greater if the participants had a greater energy intake. Put simply, studies that control energy status - one group at ~maintenance energy vs. another group in an energy surplus - are required to answer this question.
Unfortunately, there is only one study of this type that included resistance training outcomes. In this study, a group at maintenance energy gained an average of 2.1% fat free mass whereas a group in a very large energy surplus (~2000 calorie/day) gained an average of 4.62% fat free mass and did not gain fat mass. However, these participants were untrained; thus, it’s unlikely these results can inform practice for trained individuals. Nonetheless, I view this study as a proof of concept of the role of an energy surplus for body composition changes.
In the absence of additional direct evidence, a few other lines of evidence can be examined.
To start, it’s clear that an energy surplus in isolation enhances gains in muscle mass. For example, an early study reported an average gain of 2.7 kg of fat free mass and 5.4 kg of fat mass after a 100-day ~840 calorie/day surplus without resistance training.
Additional insight can be gained from a 6-year observational study of 12 rugby players, presumably performing regular resistance training. The authors reported individual data for changes in lean mass and fat mass, which allows us to dig deeper into factors that may predict a high degree of muscle mass gain. I extracted this data and ran a basic correlation - as seen below, greater increases in lean mass over the 6-year period were associated with greater increases in fat mass. While this relationship wasn’t quite statistically significant, the association can be categorized as moderate.
This is not to say that you have to carry more body fat forever to maximize muscle gain. You could simply do an efficient cutting phase to drop body fat and maintain most or all of the gained muscle mass. In the studied rugby players, I strongly suspect they didn’t have dedicated cutting phases; thus, this is indication that some body fat gain is necessary to maximize muscle growth (as we’d expect in a bulking phase).
Finally, we can extrapolate from the well-established finding that an energy deficit attenuates muscle growth. As seen below, a recent meta-analysis indicated that as the energy deficit increases, muscle growth becomes less likely.
This analysis does not provide direct evidence of the benefits of an energy surplus on muscle growth; however, I strongly suspect this relationship continues past the point of energy balance.
Although there is no direct evidence in trained individuals comparing long-term bodyweight maintenance versus cut/bulk cycles, the above lines of evidence indicate that an energy surplus is likely required to maximize muscle growth.
Pros and Cons of Each Approach
While an energy surplus seems to maximize muscle growth, weight gain typically necessitates an energy deficit in the future to remove undesired body fat. This points to the primary benefits of long-term weight maintenance: consistency and simplicity.
However, if taking a bulk/cut approach, this excess body fat can be minimized with a smaller surplus. Indeed, the two studies (one, two) we currently have on rates of weight gain in trained individuals indicate that the ratio of muscle:fat gain worsens with a greater surplus.
Anecdotally, another benefit to an energy surplus is that it serves as an insurance policy. To achieve body recomposition via long-term weight maintenance, your “boxes” - sleep quality & quantity, nutrition timing, schedule optimization for training, stress levels - become vital. Optimizing these variables should be the goal for lifters, but life happens. I view an energy surplus as a better default as it provides a bit of wiggle room for progress to occur.
Individualization
In addition to deciding which approach best fits your preferences and lifestyle, the optimal approach likely varies from individual to individual. In the mentioned studies demonstrating body recomposition, I only discussed the averages. Some participants likely experienced dramatic recomposition whereas others did not. Indeed, in the study by Antonio and colleagues, the authors noted extreme inter-individual variability. Some participants simultaneously gained 7 kg of fat free mass and lost 4 kg of fat mass whereas others lost fat free mass and gained fat mass.
Another avenue to conceptualize inherent individual differences is with the previously mentioned study that utilized a 100-day ~840 calorie/day surplus. In this study, the participants were 12 pairs of identical twins. There was ~3 times more variance between groups of twins compared to within groups of twins in measures of body composition, indicating a strong genetic component to the response to an energy surplus.
The practical implications of this inter-individual variability, in my opinion, are most relevant to long-term maintenance. Some individuals - likely those with a better inherent tendency to store nutrients as muscle tissue - may be able to experience dramatic body recomposition with long-term weight maintenance. Those on the other end of the spectrum may require an energy surplus to experience meaningful muscle growth.
Application
Our interpretation of the available literature leads us to recommend maximizing the amount of time most lifters are in an energy surplus (scenario B in the original question). While I mentioned the potential benefits of a slower rate of gain, going too slow can make the weight gain undetectable. Typically, the sweet spot is in the ballpark of +0.1-0.4% bodyweight/week. Fat loss phases of -0.25-1% body weight/week as well as maintenance phases can be strategically implemented based on the training phase (as discussed in our Nutritional Periodization course).
With that said, long-term weight maintenance can be a viable option, especially when this better fits the individual’s preferences. Whether this approach can lead to meaningful body composition improvements likely differs from individual to individual (collecting individual-level data is key).
To inform your own approach, simply test the waters. Try out an energy surplus and see how much muscle you gain in 3-6 months. If you’re completely satisfied with the muscle growth experienced, you may not need the surplus and can try a maintenance approach going forward. If you were less-than-satisfied, it’s unlikely that removing the energy surplus will do anything but attenuate muscle growth.