Bulking and cutting are the two cycles used by the typical bodybuilder - gaining weight and losing weight - in order to maximize muscle mass.
Beginners probably don’t need to worry too much about bulking and cutting since they’ll progress pretty quickly even without serious changes in diet, but as you get more advanced, it becomes more and more important for your diet to match your training goals.
Knowing when to bulk and when to cut is an important part of your planning process to maximize your results. Use the guidelines and information in this post to guide your planning.
A commonly asked question when training for muscle mass is the very simple one: when should I bulk, and when should I cut?
As you probably already know, a bulk is a period in which you’re purposefully eating more calories than you need, gaining muscle mass but also gaining fat mass in the process. Then, in a cut, you’re losing both muscle mass and fat mass, but ideally more of the latter and less of the former. By keeping your diet tight (eating enough protein) and training hard, you can ensure that you gain as much muscle mass and as little fat mass as possible during the bulking phase, and you can lose as much fat mass and as little muscle mass as possible during the cutting phase.
The second most asked question is “do I have to worry about bulking and cutting?” After all, bulking and cutting is a lot of work, and requires big changes in your diet. Many novices don’t really want to go through the effort required.
Recomposition is the word we use for what happens when we build muscle mass and lose body fat simultaneously, without much change in total body mass - in short, building muscle without bulking or cutting. Recomposition is very possible in certain scenarios, especially for beginners, who gain muscle quickly, or for people using vitamin S. However, as your results begin to quickly slow down the longer you train, recomposition becomes less and less doable, and you’re likely to stagnate. After a few years of training, you’ll probably need to bulk and cut in order to continue to see serious results.
The general rule of thumb is very simple. When starting a bulk, you tend to build more muscle if you’re leaner to begin with. As you gain fat mass, insulin sensitivity decreases, making it harder to build more muscle. This simple rule makes it easy to determine whether we want to bulk or cut - if you’ve got a decent amount of excess fat mass, it’s more productive to cut. If you’re pretty lean, then it’s more productive to bulk.
Now, again, you probably know this already. Saying “bulk when you’re lean and cut when you’re big” isn’t especially surprising news.
So here’s a more specific number: 10-15% bodyfat for men or about 17-22% for women. This is the “sweet spot” range that you’ll want to spend most of your training time in. Much below 10/17%, and you’ll definitely want to bulk, because there’s not much fat mass to lose and you’ll probably start losing muscle more than anything. Much above 15/22%, and you’ll definitely want to cut as the effectiveness of your muscle-building training goes down.
Conversely, if you’re someone who’s training for strength, it’s probably fine to hover closer to 12-15%/19-22% and not worry too much about your bodyfat unless you’re specifically looking to bulk or cut in order to be more competitive within your weight class.
There is one exception to this rule - and that’s beginners. As mentioned above, beginners progress much faster than more experienced lifters, and aside from that, many of them are lighter/leaner to begin with. So, they can often continue to gain mass/weight without gaining too much fat in the process, even if they’re starting out at closer to 15% bodyfat.
In this case, I often recommend that beginners try out a bulk to begin with, if they’re willing to go for it and don’t just want to do recomposition. Typically, I see lifters like this continue to gain weight without their bodyfat changing much at all - although if they start to hit the 17-20%/24-27% range, it’s not a good idea to keep going much further.
Another lesser-known fact is that there are limits on how fast you can cut and bulk without causing unwanted muscle loss or fat gain. Generally, a slow and steady approach is superior to a bulk where you eat everything in sight or a cut where you starve yourself to lose weight as fast as possible.
That said, sometimes we need to compress our plans a bit if we’re preparing for a specific event. If you have a bodybuilding competition or a photoshoot to prepare for, you need to be as lean as possible on that day. If you’re a powerlifter looking to cut weight to fit into a specific weight class, then the same rules apply. Sometimes it may be smart to take a faster approach if needed to suit that kind of schedule - but otherwise, conservative weight gain and loss tend to produce better results.
This should give you a good idea of the best practices for bulking and cutting, as well as when to cut and bulk. In many cases, it’s fine to do neither if you’re a beginner focusing on recomposition, or if you’re training for something other than strength, but it’ll become a necessity as you gain muscle mass and become more experienced.
About Adam Fisher
Adam is an experienced fitness coach and blogger who's been blogging for 5+ years, coaching for 6+ years, and lifting for 12+ years. He's written for numerous major health publications, including Personal Trainer Development Center, T-Nation, Bodybuilding.com, Fitocracy, and Juggernaut Training Systems.
During that time he has coached hundreds of individuals of all levels of fitness, including competitive powerlifters and older exercisers regaining the strength to walk up a flight of stairs. His own training revolves around powerlifting and bodybuilding.
Adam writes about fitness, health, science, philosophy, personal finance, self-improvement, productivity, the good life, and everything else that interests him. When he's not writing or lifting, he's usually hanging out with his cat or feeding his video game addiction.
Enjoy this post? Share the gains!
Ready to be your best self? Check out the Better book series, or download the sample chapters by signing up for our mailing list. Signing up for the mailing list also gets you two free exercise programs: GAINS, a well-rounded program for beginners, and Deadlift Every Day, an elite program for maximizing your strength with high frequency deadlifting.
Interested in coaching to maximize your results? Inquire here. If you don’t have the money for books or long term coaching, but still want to support the site, sign up for the mailing list or consider donating a small monthly amount to my Patreon.
Some of the links in this post may be affiliate links. For more info, check out my affiliate disclosure.