In online fitness communities that focus on weight change, it’s impossible to avoid one completely ubiquitous question: should I bulk or cut? Or, for those unfamiliar with gym lingo: should I aim to gain weight or lose weight?
This may seem like a perplexing question if you’ve spent most of your life awash in diet culture that encourages everyone to try to lose weight and be smaller, but many people with athletic, fitness, or physique-related aspirations have goals for which weight gain can be beneficial. Being heavier can be an advantage in certain sports, and it’s much easier to build muscle while in an energy surplus. But, the “bulk or cut” question comes up so frequently because the advantages of gaining weight are weighed against health-related concerns associated with carrying more body fat, and aesthetic preferences related to a desire to achieve or maintain a particular level of leanness.
A quick note before I dive in: this article is written (and the “bulk or cut” quiz below is made) with the assumption that you’re lifting weights, or engaging in some other form of challenging structured resistance exercise. I feel like it’s a safe assumption that most people reading this article lift weights already (the “bulk or cut” terminology is fairly specific to the resistance training subculture), but if that doesn’t describe you, some advice in this article may not be applicable, as it assumes you’d be gaining weight for the purpose of building muscle. However, if you’re not currently following a structured resistance training program, but you’re interested in lifting, I’d encourage you to start – it’s great, and there’s no better time than the present.
Furthermore, the question of, “should I bulk or cut” is usually asked by people who have the long-term goal of being both leaner and considerably more muscular. So, this article is written (and the “bulk or cut” quiz below was made) with those goals in mind.
Looking for a quick answer? Take the free “Bulk or Cut” quiz below.
Returning to the topic at hand, our actual advice for most people, most of the time is simple: go with whichever option excites you more. If you can’t decide, or you don’t have a strong preference, there’s never any issue with spending some time at maintenance.
The “bulk or cut” decision is usually driven by a desire to be both leaner and more muscular. If you aim to gain weight, you’ll have an easier time building muscle, but you’re likely to temporarily lose a bit of leanness. If you aim to lose weight, you’ll get leaner, but you’ll have a harder time building muscle (and you may even temporarily lose a bit of muscle, depending on how lean you get, and how aggressively you diet). Since neither option perfectly aligns with your long-term goals, that can make it difficult to decide between bulking or cutting.
However, maintaining weight – when paired with sufficient protein intake and an adequate resistance training regimen – can usually allow people to achieve some degree of body recomposition: simultaneously losing fat and gaining muscle. So, if you’re not excited to bulk or cut, or you don’t want to deal with the temporary downsides associated with either gaining or losing weight, spending some time at maintenance is a great default option.
At maintenance, you won’t build muscle as quickly as you would when bulking, or lose fat as quickly as you would when cutting, but most people can still make some progress on both fronts at maintenance. Many people have a tendency to want to pursue something at a maximal rate at all times – either aiming to build muscle as quickly as possible, or lose fat as quickly as possible – but you don’t need to either be actively gaining or losing weight at all times. Spending some time at maintenance is very rarely a bad option.
With that being said, most of the time, if:
- You’d like to be more muscular
- You’re torn between bulking and cutting, and
- You’re also not enthused about spending time at maintenance
Then our typical recommendation would be to bulk.
Building muscle takes a long time, unless you either respond particularly well to resistance training, or you’re using chemical enhancement. Most drug-free male lifters wind up with around 20-30 more pounds of total fat-free mass (most of which would be muscle) than they started with. For women, it’s around 12-20 pounds. Furthermore, the largest chunk of muscle growth occurs during the first year of lifting, and the rest is gained very gradually over the next 5-10+ years. Losing 20 pounds of fat, on the other hand, takes a few months.
As training experience increases, it becomes harder to build muscle in an energy deficit, and eventually, it also becomes harder and harder to build muscle while maintaining weight. So, to maximize your muscle growth over time, you need to spend a lot of time in neutral-to-positive energy balance: either maintaining or gaining weight.
So, if there’s an acute reason why you want or need to be lighter or leaner in the next few months, then by all means, you should be perfectly confident and comfortable spending some more time cutting and losing weight. But otherwise, cutting moves you closer to your goal of being leaner in the short term, while increasing the amount of time it will take to achieve your long-term goal of being both leaner and considerably more muscular.
Long story short: if you’re not sure whether you should bulk or cut, we’d generally recommend either maintaining or bulking. Maintaining will generally allow you to both lose fat and gain muscle, moving you closer to both of your long-term goals (albeit not at the maximal possible rate). Bulking, on the other hand, will help you build muscle faster, and muscle growth requires much more time than fat loss. So, if you have the long-term goal of being both leaner and more muscular, most of your time should be spent in neutral-to-positive energy balance, either gaining or maintaining weight.
Reasons you might want to cut
So, our default answer to the question of “should I bulk or cut?” is to go with whichever option excites you more. But, if you don’t have a strong preference between bulking and cutting, we’d typically recommend either bulking or spending some time at maintenance. With that said, there are some considerations that may (or may not) make it preferable to cut. So, let’s explore those considerations.
Health
One reason you might want to cut would be due to health-related concerns from carrying too much body fat. As adiposity increases, so do rates of insulin resistance, high blood pressure, elevated blood lipids, and other predictors of cardiometabolic disease risk, but all of these risks increase in a nonlinear fashion. So, at what point do elevated levels of body fat begin increasing long-term health risks?
Around 25% body fat for men, and around 35% body fat for women.
I think that’s a bit higher than most people in the fitness world suspect, due to how frequently leanness is presented as a proxy for health. It’s not uncommon for people to believe that men shouldn’t get above 15% body fat, and women shouldn’t exceed 25%, but research suggests that there’s quite a bit more wiggle room.
Now, those are just population-level estimates. For more personalized insights, you could monitor your cardiometabolic disease risk factors with the help of a medical professional to determine health-related body fat cutoffs for yourself. Furthermore, we pass no judgment on differing methods of assessing risk. You might want to ensure you stay 5% below these thresholds (20% for men and 30% for women) to take a “better safe than sorry” approach, or you might be comfortable with the small increase in risk that comes from exceeding these thresholds by 5% (30% for men and 40% for women). Or, this may not even be a significant consideration for you in the first place.
But, to the extent that health-related concerns impact your decision to bulk or cut, men might want to consider cutting if they’re above 25% body fat, and women might want to consider cutting if they’re above 35% body fat.
Enhanced muscle growth when you’re leaner?
One common reason people provide for wanting to cut is the belief that they’ll build muscle more effectively when they’re leaner. However, this belief appears to be erroneous.
The belief that leanness enhances muscle growth largely stems from overfeeding studies analyzed by Forbes in a popular paper published in 2000. His analysis suggested that when leaner people gain weight in response to overfeeding, up to 80% of the weight they gain is lean body mass. However, when people with more body fat gain weight in response to overfeeding, their lean mass gains may account for less than 40% of their total weight gain.
However, there’s good reason to believe that these results don’t generalize to “bulk vs. cut” decisions.
One major factor here is path-dependence. In other words, the physiology of naturally lean people isn’t identical to the physiology of people who are similarly lean following weight loss. Naturally lean people are naturally lean because they have a lower propensity to gain fat in general. People who are lean following weight loss typically had to lose weight to get lean because they had a greater natural propensity to gain fat in the first place. Forbes’s paper suggests that overfeeding preferentially increases lean mass in naturally lean people, but experimental evidence suggests that fat is preferentially regained with refeeding following intentional weight loss.
Another major factor is the nature of the interventions used in the studies included in the Forbes paper. Resistance training is the single largest (legal and controllable) factor influencing muscle growth, but the studies Forbes analyzed involved overfeeding without a resistance training stimulus. I don’t think it would surprise anyone that overfeeding alone would primarily cause fat gain in people who already have high levels of body fat, but that tells you absolutely nothing about the ability of these individuals to build muscle in response to resistance training in an energy surplus.
A final factor is that the populations assessed in some of the studies Forbes analyzed were unique populations that likely have unique responses to overfeeding. Namely, some of the overfeeding studies in very lean people were weight regain studies in anorexic patients. And, while fat may be preferentially regained following “normal” weight loss, severe anorexia can significantly reduce the mass of internal organs and other critical lean tissues. Upon refeeding, these tissues may preferentially increase in size again, before fat mass begins replenishing. In a 2007 re-analysis of this topic, Dr. Kevin Hall notes that, “a referee kindly pointed out that the weight gain data originally presented by Forbes in support of his theory included data from weight regain studies in anorexic patients…after removing the data from the anorexic subjects with very low initial [fat mass], there was insufficient evidence of a relationship between the composition of weight gain and the initial [fat mass].”
With that in mind, we performed a subject-level meta-regression of studies with open data, reporting gains in fat-free mass following resistance training in subjects with differing levels of initial body fat. In both men and women, we found no relationship between baseline body fat percentage, and gains in fat-free mass following resistance training.
So, if you have a goal of building muscle, we don’t think that the decision to cut should be predicated on the assumption that you’ll more effectively build muscle following your cut. The belief that you’ll build muscle faster when you’re leaner (following a cut) is based on data from studies and populations that aren’t particularly applicable to most people who lift weights. Furthermore, the data in people who do lift weights suggests that body fat levels don’t impact your ability to build muscle.
Aesthetic preferences
For many (perhaps most) people, I think decisions to cut are primarily influenced by aesthetic preferences, which is entirely understandable. If your goal is to be both leaner and more muscular, you probably don’t want to gradually build muscle for the next 10 years, and never check in on your lean physique in the intervening years.
So, if you want to cut just because you prefer how you look when you’re leaner, go for it!
I think there’s a general tendency for people to feel like they need to justify their desire to look a certain way. I suspect that’s a major factor motivating people to promote the idea that being super lean is necessary for health and longevity, and the idea that being leaner enhances muscle growth. Those ideas may sound more “worthy” or “noble” than simply saying, “I prefer how I look and/or I like the type of attention I get when I’m leaner.” But, I think we’re deluding ourselves if we can’t acknowledge the fact that aesthetic preferences are a major reason (perhaps the primary reason) many people want to lose weight in the first place. There’s no need to feel any shame about that, and you shouldn’t need to justify it – just embrace it.
Circling back to the start of the article, we said:
If you’re deciding whether to bulk or cut, our actual advice for most people, most of the time is simple: go with whichever option excites you more.
If you’re excited by the prospect of being leaner in the next few months, that’s all the reason you should need to pursue that goal.
Competitive reasons
For some people reading this, sport-related concerns may make cutting advisable in certain situations. It would be impossible to address every contextual factor in every sport that may influence this decision, but if you compete in sports, I suspect you already have a decent grasp of the relevant considerations for your particular sport. But, here are some high-level considerations that might make cutting an attractive option.
In many sports, competitive success is strongly influenced by speed, jump height, and the ability to rapidly accelerate, decelerate, and change directions. All of those capacities are influenced by power-to-weight ratios, so cutting some body fat might improve your competitiveness.
Many other sports have weight classes, and it’s usually best to fit into the lightest weight class you can manage without compromising your performance. If you’re 80kg, the next weight class down is 72kg, and you think you could get below 72kg without sacrificing performance, you’ll probably have more competitive success (at least in the short-term) at 72kg than in a class with a weight limit of >80kg.
In endurance sports, losing fat generally increases your absolute movement economy. More mass requires greater energy expenditure to maintain a particular speed of movement, and it increases the total energy cost of covering a particular distance. This is especially salient if you’re training for a race with significant elevation change.
Finally, for physique sports, leanness is one of the primary criteria that you’re judged upon. If you need to be 6% body fat on stage, and you’re currently 15% body fat at 20 weeks out from a show, you’ll obviously need to cut before stepping on stage if you’d like to make it onto the podium.
However, in many sports, it’s also advantageous to build muscle to increase your ability to generate force and power. This goal is facilitated by bulking or maintaining. So, you’ll need to balance long-term development against considerations of near-term competitiveness.
Burned out from bulking
One final consideration is that bulking can simply burn some people out. If you’re a naturally skinny person with a small appetite and a very high total daily energy expenditure, eating hundreds of calories per day beyond what your appetite would dictate can become a grind after months of being in an energy surplus. In the same way many people feel the need to take a break from cutting after a while, you may feel the same need to take a break from bulking.
In general, for pursuing the goal of building muscle, spending some time at maintenance is likely preferable (in a vacuum) to cutting. But, eating enough to just maintain a higher body weight may still be a slog. So, if you feel like a short cut will give you the psychological break you need to pursue a surplus again, I’d never tell you that you’re wrong if you want to cut for a few weeks.
So, should you bulk or cut? Ultimately, the decision is up to you, but this decision tree should help you narrow it down, based on the factors and considerations we’ve covered in this article. The “bulk or cut” quiz at the top of the page simply takes you through this decision tree.
That wraps it up for this article. The next two articles in this series discuss the optimal rates of weight gain to facilitate muscle growth while minimizing fat gain, and the optimal rates of weight loss to facilitate fat loss while maximizing muscle retention.
