Should You Cut Or Build? (Understanding P-Ratio With Brandon DaCruz)


Today, Brandon DaCruz and I are taking a deep dive into the topic of the P-Ratio (partitioning ratio).

You’ve may have heard that women and men need to in a very specific body fat range when trying to build lean muscle in order to optimize the the way your body partitions nutrients. 

Within this “ideal body fat range”, you’ll be able to gain lean muscle while mostly avoiding fat gain... but outside of it, you’ll gain mostly fat and very little muscle. 

But is there any truth to this concept? 

You'll get these questions answered (and much more) today as we dig into: 

 1: What is the p-ratio? 

 2: Common misconceptions about the p-ratio 

3: Main factors that influence the p-ratio and nutrient partitioning 

4: How does someone's body fat level impact nutrient partitioning? 

5: ”I’ve heard the argument that those with the highest levels of FFMI like college football players also have high levels of body fat... so that must mean that their ability to gain muscle isn’t impaired by body fat. What’re your thoughts on that?” 

6: Many of the debates around the optimal p ratio involve body fat and how it affects hormones and inflammation... so how does body fat impact hormones and inflammation? 

7: How do you approach building phases with your clients and maximize their p-ratio? 

8: Practical applications for the listener

If you'd rather listen to the podcast version of our interview, CLICK HERE.

[*Brandon deserves credit for most of the points and concepts below. I've expanded on his thoughts a bit where helpful, but highly recommend you listen to the episode as well to fully understand the context of the conversation.]


The partitioning ratio refers to how well you partition nutrients into muscle tissue vs. fat tissue. 

So in relation to building muscle, this concept describes the ratio of muscle gained to fat gained:

→ If someone had a high p-ratio, it would mean that for every pound gained, the added weight is mostly muscle, with very little fat gain (they're making "lean gains").

→ But having a low p-ratio means you'd gain mostly fat with very little muscle for ever pound gained.

Generally you'll hear people say (*NOTE: this isn't necessarily true) that...

→ Women between 20-25% body fat

→ Men between 10-15% body fat

...will have the best p-ratio. But outside of these range, for every pound of body fat that you gain, you'll gain much more fat tissue than muscle tissue. So it makes sense to start a fat loss phase when you approach the upper end of this range to prevent excess fat gain, and set yourself up to make more "lean gains" once you're leaner again.

But again, it's important to understand that there is much more nuance than just these ranges.


There are quite a few common misconceptions about the p-ratio, but the most common one:

The leaner you are, the better your p-ratio will be.

You'll often hear bodybuilders talk about about the idea that you're "primed to grow" after getting extremely lean.

The reality is, your body is much more primed for fat gain than muscle gain at the end of a diet where you've gotten very lean (think: photoshoot or bodybuilding stage levels of lean).

Your body needs some fat in order to maintain health, so when you diet to an extremely lean state your body will prioritize regaining fat tissue over muscle tissue - it needs to feel healthy (which does require some body fat) before it would make sense to put on lots of calorie-expensive muscle tissue.

So there is definitely a point where you can be too lean, and it will actually lower your p-ratio until you regain some body fat. It may be counterproductive trying to get too lean before a building phase if your goal is improving your p-ratio.

That said, the p-ratio does usually seem to work well in the opposite direction - individuals with a larger amount of body fat to lose are often capable of body recomposition (losing fat and building muscle at the same time) within online coaching (so they have a "high p-ratio"), as their bodies have more body fat/energy stores to use as fuel while still gaining muscle.  

But the most important thing to understand is that we each have an individual response to the p-ratio, based on where our body fat naturally tends to settle.


If someone was obese most of their life, but got into training and got lean by taking their calories extremely low, this would not necessarily change their p-ratio. 

They wouldn't get extremely lean, and then put on more muscle mass and less fat mass as a result of now being 10% body fat. Really, they'd likely be predisposed to gaining more body fat, due to the body fat overshooting effect

Now, this definitely isn't to say that you shouldn't try to get lean and improve your p-ratio. It just means that rather than focusing on whether your body fat is in the ideal range to build... we need to focus on multiple factors outside of just body fat that influence the way our body partitions nutrients. 

The actual body fat percentage you're at is likely less important to p-ratio than many other factors.

All that said, for metabolic health, managing inflammation, and preserving insulin sensitivity: Staying in approximately the ~18-30% body fat range for women and 10-20% range for men is likely ideal.  

Having higher body fat than this doesn’t necessarily hurt your ability to add lean muscle tissue… but it does have some detriments to your health that can have long-term health consequences.


→ TRAINING: Really the most powerful thing you can do to improve your nutrient partitioning.

- It increases sensitivity to amino acids for up to ~ 24 hours post-workout, which means your body better utilizes dietary protein and increases the process of muscle protein synthesis (the process of your body turning dietary protein into muscle).

- Increases glucose (carb) uptake without insulin. Basically, it lowers our body's need for insulin as a shuttling agent, while still sending amino acids and glucose to muscle cells.

→ CURRENT LEVELS OF LEAN MUSCLE: You can essentially see muscle as a "sink" for glucose/carbs. The more muscle you have, the more carbs will be stored as muscle glycogen rather than in your fat cells. So basically more carbs will be stored in muscle vs. fat. 

→ LEVELS OF INSULIN SENSITIVITY: A.k.a. how sensitive our bodies are to the effects of insulin. Those with high levels of peripheral insulin sensitivity are able to uptake far more glucose into their muscle cells, so that more carbs are stored as muscle glycogen rather than in fat tissue.

So exercise of course increases insulin sensitivity.

→ PHYSICAL ACTIVITY OUTSIDE OF THE GYM: Cardio, daily steps, etc. Very similar to resistance training, doing more activity outside of the gym will yield better insulin sensitivity.

NUTRITION: The size of calorie surplus used in a building phase of course influences the amount of extra calories we have available to be shuttled towards muscle or fat cells on a daily basis, which in turn impacts how much muscle vs. fat we gain in any given timeframe.

The reality is, we can't force feed muscle growth. As you get more advanced in your level of physique development, you likely won't need as large a surplus to build muscle as compared to someone who is newer to proper training and nutrition.

This is because as you get more advanced, the rate of muscle gain you're capable of is slower, and thus you need fewer calories in a surplus, as your body is building less muscle than a beginner.

So an advanced individual with a very large surplus in a building phase will likely gain more fat and less muscle vs. a relative beginner.

BODY FAT PERCENTAGE: The old P-ratio concept was... 

Low body fat = more muscle, less fat gain

Higher body fat = More fat gain, less muscle 

...Which isn’t necessarily true - both to high and too low of body fat negatively impacts insulin sensitivity.  

When you’re too lean (think: bodybuilding stage or photoshoot lean), your fat cells are going to be primed to grow.   

If you have too much body fat especially visceral fat (fat stored around your organs) you’re going to see a rapid decline in insulin sensitivity and an increase in insulin resistance.

This increase in insulin resistance seems to generally start happening for men > 20% body fat, women > 30% body fat. 

So essentially, for the best nutrient partitioning, you need to be at a healthy body fat level (neither too high or too low)

As Brandon says: A healthy body is a responsive body

Finally, realize that insulin sensitivity can also be impacted by your sleep quality, stress management, nutrient availability, and more. 


WHAT IS THE BODY FAT PERCENTAGE RANGE THAT YOU CAN MAINTAIN COMFORTABLY? This will vary quite a bit between individuals, but we want to be within a range of body fat that you can maintain with relative ease (you shouldn't have to feel like you're working too hard to stay lean). For some women, this could be 18-22% body fat, for others 22-26%.

→ SET AN APPROPRIATE SURPLUS: How people respond to a calorie surplus will vary a lot between individual. Some people will move more/burn more calories as a response to eating more food (and thus will need a larger surplus for it to be effective) whereas others will need far fewer calories to maintain a surplus in a building phase.

So rather than aiming to eat ___ number of calories above maintenance, it's smart to adjust your food intake to the point where you're gaining ~.25-.5% of your body weight per week. 

If you're more advanced, it's generally smart to lean towards the lower end of this range (.25%) if a beginner, more towards the higher end (.5%).

→ CHOOSE THE RIGHT TRAINING STIMULUS: If your goal is building muscle, your training needs to be mostly specific to hypertrophy (muscle growth). Learn more about how. to train to build muscle with our Hypertrophy Training Guide.

→ OPTIMIZE YOUR NUTRIENT-TIMING: It likely makes the most sense to prioritize getting a large portion of your daily calories (and carbs especially) in your pre and post-workout meals.

Learn more about optimizing nutrient timing HERE.

→ RECOVERY ABILITY: You don't build muscle just as a response to working hard in the gym. Your ability to grow muscle is limited by what your body can actually recover from.

So you need to prioritize recovery for a productive building phase. Nutrition, stress management, sleep, and smart training programming like our clients follow are key here.

USE A PHASIC APPROACH TO CHANGING YOUR BODY COMPOSITION: No phase of nutrition should last forever. We know that for the best health and body composition, using a phasic approach to changing body composition like we use with our clients is vital:

[To grab a 100% free guide that gives you a simple breakdown of our Phasic Dieting Method that you can implement immediately to FINALLY see the results you’ve been chasing for years, just click here.]


First, understand that we're very much speaking in generalities here. As you've learned above, there is a lot of nuance to consider. That said:

→ If you’re a male between 8-15% body fat, you're likely still lean enough to enter a building phase. However, once you get between ~18-20% body fat (mind you, this will be dependent on where your body fat settling point is, where you’re comfortable, what your metabolic health markers are, how many calories you’re eating) - but from a broad perspective, if you’re over this point, it’s a good idea to enter a mini cut or fat loss phase to mitigate the negative effects of higher body fat. 

→ As a female 18-26% body fat, you’re likely in a good position to enter a building phase, but over ~30% we’d generally suggest a fat loss phase or mini-cut. 

That said, women are much less to adding visceral body fat and have better metabolic health at higher body fat percentages than males. Women predominantly store fat in hips and thighs, and tend to get leaner in the abdomen before men, but tend to store less "unhealthy" body fat. 

But keep in mind, these are ranges and recommendations. Exact body fat percentages are very difficult to gauge. 

 To determine the best course of action go forward for a client, we’re looking not only at body fat and body composition, but subjective data and biofeedback as well. 

If someone looks like they’re 18% body fat, but they’re…  

 - Starting to feel lethargic (especially after meals) 

- Losing pumps in the gym 

- Fasted blood glucose  levels are increasing

...understand that these are all signs you're likely starting to get to a more insulin resistant state, and your cells aren’t uptaking glucose as effectively, so it might be time to shave off some body fat and improve these markers with a fat loss phase before focusing on building.


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If you found this helpful but need some help creating a personalized training and nutrition plan to hit your physique goals, click here now to schedule a free discovery call with our coaching team.

written for you by jeremiah bair

I love simplifying the mysterious art and science of training and looking like it. I’ve been on my own journey, and I share what I’ve learned so you can get there faster, on my Podcast and Instagram.

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