There’s a common practice in the bodybuilding world that’s slowly made its way into regular fitness- bulking and cutting. For those of you unaware, bulking and cutting is a strategy for optimizing one’s physique by going through different cycles of either extreme calorie gain or deprivation. In other words, you’re either eating an insane amount of calories to gain weight (or muscle) or drastically lowering your calories to lose weight (or fat). Does the bulk-cut cycle have its place, or is there a better way to improve body composition? Let’s cover the pros and cons in today’s post!

The Pros

While body composition requires several lifestyle practices- from proper exercise to sleep- there’s no denying the importance of nutrition. Your diet can make or break your looks when it comes to fat, muscle, and shape. So, manipulating your calories makes perfect sense and is a valid practice. 

From a pure calorie-counting perspective, the bulk-cut cycle teaches the power of nutrition and how it affects your physique. Beginners will gain a general understanding of how much calories, fat, carbs, and protein is in their food. After a while, they’ll ideally no longer need to rely on counting and measuring and can eyeball their food using portion control and intuitive eating. 

Bulking

Bulking is part of muscle growth. If you want to build muscle, then you need to supply your body with the right nutrients. That way, your body can replace the broken-down tissues with stronger, resilient ones. Doing so while undereating is extremely hard to do. In some people who genetically blessed, this can easily be done, but they’re the exception. Most people need to eat more to build muscle. And at the very least it’s one of the quicker ways of reaching this goal. 

For my nerds out there, here’s a bit of muscle science. This comes from strength and conditioning expert Bret Contreras (aka, the Glute Guy). Bret explains that during resistance training, you increase myonuclei, which are the “synthetic engine of muscle fibers.” Recent research shows that they allow further muscle growth even after periods of under-training, acting as a “memory bank,” allowing you to jump right back in and continue building new muscle. They’re the science behind “muscle memory”! Cool, huh? [1]

But back to myonuclei and bulking. When you’re eating more calories (aka, a surplus) and training to build muscle, you enter what’s known as an anabolic state. As Contreras explains, “When you’re in an anabolic state, it’s much easier to grow muscle. And when you’re growing muscle, satellite cells will ‘do their thang.’ Satellite cells surrounding the muscle cells will donate their nuclei to the muscle cells so that they increase their total number of nuclei… This translates into greater potential muscle mass. There’s a ‘myonuclear domain’ theory that postulates that the growth of a muscle is limited by the nuclei it contains. When you diet back down, you will retain these myonuclei, which will be useful in maintaining muscle mass and improving body composition.” [2]

OK, that was a lot to unpack. Here’s a summary. Resistance training increases myonuclei in the muscles. When bulking (increasing calories) comes into the picture, you enter an anabolic state where the potential to build more muscle increases. At the same time, you’re increasing myonuclei, which many experts (Contreras included) believe increases muscle growth. More myonuclei, more muscles. All of this is supercharged by increasing your calories. 

Cutting

The benefits of cutting don’t need much of an introduction. It’s just calorie restriction. When you’re training intensely and burning off an already-low amount of calories, you lose weight (and possibly fat). No rocket science there. Many people “cut” without even knowing it! 

As far as benefits go, research shows that calorie restriction (both with and without exercise) improves insulin sensitivity and lowering body fat. Which is why it’s an excellent tool for improving or preventing metabolism-related disorders like type 2 diabetes. In animal studies, it may even increase lifespan. [3]

The Cons

Nothing is perfect. The bulk-cut cycle is not without its drawbacks or its critics. Here are the cons of bulking and cutting.

Bulking

Even though you’re packing on muscle during a bulk, you’re also putting on fat. Expert Bret Contreras also has an opinion on the fat-gain that comes from bulking, explaining, “Unfortunately, fat cells grow as well, and they can also undergo hyperplasia… When you lose weight, you will retain this increased number of fat cells. Furthermore, when bulking, you can easily decrease insulin sensitivity, and the binging can become habitual and somewhat addictive, causing some folks to struggle when attempting to diet back down.” [2] 

Bulking encourages both fat gain and unhealthy habits, like binging and food addiction. Not only that, it will make the transition either over to cutting or “normal” eating that much more difficult because you’re so used to eating tons of food and calories. Increasing fat also lowers insulin sensitivity, which sets the stage for things like blood sugar imbalances, diabetes, and metabolic syndrome. Metabolic syndrome itself is a problem since it increases the risk of heart disease and stroke. But the bad news keeps on coming. Having either extra weight or fat often brings other symptoms like sleep apnea, high LDL (bad) cholesterol, and hypertension (high blood pressure). [5] [6]

Cutting

Cutting can be just as bad. It’s a slippery slope when it comes to lowering your calories. If you’re not too careful, you could cause severe damage. Especially with your hormones. In women, this can result in amenorrhea, or missing period (which in and of itself is a dangerous state linked to heart attacks, bone loss, poor digestion, and sleep problems, amongst others). [7] Cutting too low and for too long also slows down the thyroid, which ironically can ruin your metabolism since the thyroid is what regulates it! [8] The only hormone that goes up is cortisol (aka, the stress hormone), which further affects metabolism and body composition. [9] You’re working against yourself when you go low calorie for too long!

Let’s not forget your mental health during a cut. Food is not only fuel, but it’s also pleasure. You shouldn’t hate the things that nourish you! Unfortunately, many eating disorders stem from severe calorie restriction. Going back to normal eating may take its toll mentally since, for the person that’s used to restricting, any increase in food is going to seem like overeating. (If that’s the case for you, please seek professional help- you’re certainly not alone, and you could use a gentle hand to guide you in the right direction towards recovery.)

The Verdict

Do you need to bulk and cut? In my opinion, there’s a better way to do that. You don’t need to overeat or starve yourself to gain or lose weight. In my opinion, slow and steady wins the race. Anything extreme is going to send your body into shock and create a host of problems (i.e., blood sugar, hormones, mood, hunger balance). For weight gain, you only need 300-500 extra calories, which can easily be increased by adding higher-calorie foods, bigger portions, extra meals, or snacks (like protein shakes). [10] With weight loss, many experts recommend eating 500-750 fewer calories than you usually consume. [11] Go easy on the snacks, increase high volume but low-calorie foods (i.e., eat your fruits and vegetables), watch your portions, and maybe consider intermittent fasting. Simple. 

There’s no perfect formula for gaining or losing weight. Everyone responds differently. One thing’s for sure, though. Anything extreme is going to lead to extreme results, and not always for the best!

Sources:

[1] https://www.sciencedaily.com/releases/2019/01/190125084106.htm
[2] https://bretcontreras.com/to-bulk-and-cut-or-not/
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2677812/pdf/nihms-49263.pdf
[4] https://www.scientificamerican.com/article/if-a-diet-of-caloricrestr/
[5] https://www.mayoclinic.org/diseases-conditions/metabolic-syndrome/symptoms-causes/syc-20351916
[6] https://www.sleepfoundation.org/articles/connection-between-weight-and-sleep-apnea
[7] https://www.mayoclinic.org/diseases-conditions/amenorrhea/symptoms-causes/syc-20369299
[8] https://www.ncbi.nlm.nih.gov/pubmed/12055988
[9] https://jissn.biomedcentral.com/track/pdf/10.1186/1550-2783-11-7
[10] https://www.healthline.com/nutrition/how-to-gain-weight
[11] https://www.verywellfit.com/how-to-cut-calories-for-weight-loss-3495810