body mass index vs bodyfat

BMI vs Bodyfat: The difference between BMI and bodyfat in bodybuilding !

Today, we’re discussing the different ways that you can measure things like bodyfat and body weight, and which ones are most useful for natural bodybuilding and bodybuilding in general.

The more time and effort you put into understanding your body, the better results you can get. Understanding what different measures do is a huge way to boost your total control of your body and how it changes.

It’s just as important to build better tools as it is to clear up misconceptions. Put your time into the most important things, and you’ll be able to get better results for every drop of effort you put into training, diet, and recovery!

Fat and Weight in Bodybuilding

In natural bodybuilding, your weight is going to fluctuate often: sometimes you’re trying to build muscle mass, which means gaining weight. Other times, you’re trying to lose weight and burn fat so that you can see your new, big muscles with a grainy physique.

These changes mean you need to understand bodyweight, body fat, and BMI – and how and why they’re different!

scales bmi body fat bodyweight measurement

In today’s article, we’re going to discuss these concepts so that you know what you’re doing, you get better control over your body transformation, and you can build a great natural physique. The better you understand how this works, the better results you can achieve.

For natural bodybuilding, knowledge is power – the power over your own body and how it changes with training and nutrition!

Bodyfat vs BMI: What’s The Difference? 

BMI is a measure of your weight-per-height ratio, while body fat is a measure of the fat tissue on your body. Confusing the two can be a real problem – since gaining weight increases your BMI but may not affect your body fat very much, or the opposite.

bmi versus muscle mass body fat percentage bodybuilding

Changing your BMI is just the result of weight gain or loss, while body fat changes are a more specific type of change. You can gain or lose weight in multiple ways – as water weight, fat, muscle, or just holding more food in your body. However, for natural bodybuilding, we don’t just want to lose weight or gain it – we want to lose fat when we lose weight and gain muscle mainly when gaining weight!

BMI in Natural Bodybuilding

We don’t use BMI very often in natural bodybuilding – but it’s a great way to compare size between heights. Since bodybuilding uses height classes, this is a good way of comparing the size of a smaller man and a larger one.

You can use BMI to check how someone’s size compares, across different height classes. Who is bigger, 230lbs at 5’9, or 250lbs at 6’? We can use a BMI calculator to get a number that doesn’t care about height and lets us compare different guys.

230lbs at 5ft 9in is a BMI of 34.0

255lbs at 6ft is a BMI of 34.1 – slightly higher!

This is a great system that you can use to measure relative weight to size. If these two men have the same bodyfat percentage, then we might think that the latter is just a little bit bigger, even if the difference is so small that you can’t see it.

natural bodybuilder bmi comparison

For bodybuilders – especially competitive natural bodybuilders – this kind of measure is important. Increasing your BMI during a bulk is great, especially for open class competitors, or  in classes with larger height ranges – where you want to know how you stack up!

Bodyfat in Natural Bodybuilding

Bodyfat is absolutely essential for Natural bodybuilding: the less bodyfat you carry with the same amount of muscle, the better. This conditioning, as it’s called, is in part – what wins shows. Being big and muscular is only half of the game – you also need to get shredded.

Natural bodybuilding typically features higher body fat percentages than bodybuilding with steroid use. Natural bodybuilders maintain higher, healthier levels of body fat both during prep and in the lead-up to competition, since they still need their fat to keep hormones stable (since they’re not injecting them!).

natural bodybuilding body fat percentage pinch man and woman

Bodyfat is something that we have to accept gaining sometimes – like when building serious muscle mass – but not something to worry about. If you have a good handle on your diet, gaining and losing fat is just a natural part of the process. 

Lower bodyfat offers better looks, but sometimes obsessing over it can limit your progress!

Statistics and Tools for Natural Bodybuilding

While they’re very different numbers, and reflect different things, both bodyfat and BMI are interesting tools you can use for your journey. They can be used to frame different goals and may break up the monotony of just going to the gym and trying to lift more weight.

Remember that your body is the goal, not just the training. Things like BMI can be interesting to track changes and compare with others in a way that is fair and balanced. I’ve seen people use BMI for goals, too: “obese but with six pack abs”, for example.

male natural bodybuilder high bmi

But these are just metrics – what matters most is how your physique looks, especially as you come around to competition. This is when you need to be in your best shape – and the goals are only important if you keep progressing in the gym and in the mirror.

Too many young bodybuilding enthusiasts – especially beginner natural bodybuilders – worry too much. The key thing is to keep training and eating better (and usually more), and you’ll progress whatever the numbers are!

How Can You Measure Body Fat?

The most popular way to measure body fat is with a skinfold calliper test – checking the amount of actual fat under the skin in key areas. However, this can be a little unreliable and you need to get them done regularly to get personalised data – and a better result!

male natural bodybuilder measuring body fat with skinfold calliper

You can measure body fat with a DEXA scan, which is a far more expensive – but more reliable – measure. Even more expensive is a water displacement test, which is the most accurate way of testing body fat levels – but requires seriously specialist kit!

One of the real challenges is that bodybuilders want to know their b odyfat percentage, but it’s hard to actually tell. Most of the tests are a little unreliable, and the main thing you notice is changes in body fat – not exact numbers.

Cutting Body Fat

Remember that cutting down too often is a waste of time and will break the momentum of your training and progress. Getting good at natural bodybuilding is about being patient and committing to extended periods of training with a clear goal.

Whether you’re getting bigger or getting shredded, you need to get involved with a structured program and diet plan. Natural bodybuilders need to accept being a little fatter during some phases of the year – you can’t stay competition-lean all year around.

natural bodybuilder bulk vs cut body fat percentage

You probably also don’t have a good idea of what a certain bodyfat percentage looks like: most bodybuilders overestimate their body fat percentage. It’s also important to consider that bigger muscles are visible at a higher bodyfat level.

Some guys have visible abs at 16% – which is because they’re more muscular, have thick abs, or store fat differently. This is important: try not to compare your bodyfat between different people, since you can’t accurately tell where they hold weight, and percentages could be quite different.

How To Lower Your Body Fat Percentage

You lower your body fat percentage by eating less calories – on average – than you use. This is a slow process but the only way to consistently lose fat, and thus lower the percentage of your total body that is fat.

High blood pressure, high cholesterol, and type 2 diabetes are linked to a high body fat percentage.

The best way to lower body fat percentage is combining both sides of the equation: eating a healthy calorie-deficit diet and exercising regularly. In bodybuilding, this means lowering your total carb intake, keeping protein intake high, and usually adding a little extra cardio to your regular weight lifting workouts.

calorie deficit diagram

If you’re looking to lose weight, aim for a slow and steady weight loss. Crash diets or fad diets might help you lose weight quickly, but they’re not sustainable and can be unhealthy. Instead, focus on making a series of smaller, sustainable changes to your diet that you can stick with in the long term.

Exercise isn’t essential – you can lose weight without it – but it’s better for health and body composition to combine the two. Losing weight without exercise is more likely to cannibalise muscle to make up the calorie deficit. Muscles are made of protein and a low-calorie, low-protein diet with no exercise is a recipe for disastrous muscle loss.

BMI Vs. Body Fat: Which Number Is More Important?

For natural bodybuilding, body fat is the more important number – even if it’s hard to get a reliable measure. It’s the number you want to bring down while keeping as much muscle mass as possible – getting leaner and improving your proportions.

To calculate your BMI, you can use this BMI calculator. A healthy BMI is generally considered to be between 18.5 and 24.9.

bmi chart

However, it’s important to note that BMI is not a perfect measure of health, as it does not take into account factors like muscle mass or body fat percentage. You can see a huge variety between people at the same BMI, depending on what their body composition is: more muscle vs more fat.

BMI for Bodybuilding: Take A Pinch of Salt

BMI is a more important number for measuring health, but only if you’re a “normal person” – bodybuilders are typically much heavier due to extra muscle mass. Consider that obesity and related problems aren’t as dangerous if you’re:

  1. More muscular: you’re carrying less fat so heart disease (e.g.) is not as much of a risk
  2. More active: regular training offsets the problems of weight, like insulin resistance.

People with a low or normal BMI, but high body fat percentage, are “skinny fat” or – accurately – “normal weight obesity”. That’s because BMI is not as important if it’s not the result of excessive body fat. We need to be careful using BMI for active people, since it may give us false alarms.

Body composition – the ratio of fat to lean tissue – is the one we want to maximise. This is the underlying balance for both bodybuilding and health, since it’s the one that makes you look better – more muscle and less fat – and is perfect for improving your health markers and lifestyle!

How To Track Your BMI

The BMI test is a simple calculation that uses your height and weight to determine if you’re at a healthy weight. You can use a BMI chart to find your starting number. You can also use an online calculator to track your BMI easily.

One great benefit of the BMI test is that you don’t need any special equipment. You can also track your BMI over time to see how your numbers change.

This is a great way to measure your progress in terms of general health. It can also help you pinpoint areas where you might need to make changes.

So: Is Measuring BMI And Body Fat Percentage Important?

If you want to live a healthy and active lifestyle, it’s crucial to track your progress. This will help you see if your efforts are paying off. It will also motivate you to keep going as you see your hard work paying off.

This can help make fitness and healthy eating seem less like a chore and more like something enjoyable. It can also make it easier to set and reach your goals.

notepad and pen

If you’re trying to lose weight, measuring your BMI is a great place to start. It can help you set realistic goals. This can make it easier to stay motivated. It can also make it easier to set realistic goals.

Fat Free Mass Index: Can You Use BMI And Body Fat Together?

Fat free Mass Index – or FFMI – is what bodybuilders typically use. This is a measure of the non-fatty tissues of the body, and thus is a great way to measure long term mass gain and “natural potential” in bodybuilding.

For natural bodybuilding, conventional wisdom says that the natural limit for FFMI is around 25-26. This should be your guideline for what you can achieve naturally – and there’s an FFMI calculator for it, just like there’s a BMI calculator for that!

ffmi calculator equation

A side-effect of using FFMI is that you can get a good idea of who is natural or not. At least, in the broad strokes, you can say for certain what is naturally possible, and what is not. Bodybuilders with an FFMI over 26, like Arnold Schwarzenegger, are not natural because they carry more fat-free mass than any natural human would be able to!

I find this really useful to get a good idea of where natural drops off and the body’s limit!

Final Words: Is BMI or Bodyfat Percentage More Important?

Bodyfat percentage is more important – but it comes down to what you’re trying to measure. BMI is a good general indicator of health, while body fat percentage is better for fitness and metabolic health.

Most experts agree that BMI is not the best measure of health. This is because BMI does not consider factors like muscle mass or body fat percentage. However, BMI can be a helpful tool to estimate whether someone is at a healthy weight. Your focus should be not only losing weight, but losing inches in places where you need to slim down, and gaining them in other places.

natural bodybuilder with tape measure

Body fat percentage is a more accurate measure of health, as it takes into account factors like muscle mass and body fat percentage. You should also consider FFMI as a good tool to check out your progress compared to what is possible naturally, and see who is lying about natty status!

The smart bodybuilders – the ones who make the best progress – know that each measure is useful for something different, and it’s all about getting the right measure for the job.

Keep Things in Perspective!

Remember that body fat percentage is just one metric of many. To get a complete picture of your health, you should also consider your waist circumference, blood pressure, and cholesterol levels. Get regular check-ups with your doctor to keep track of these key health markers.

There are many reasons why it’s beneficial to keep track of both your BMI and body fat percentage. For one, it’s a great way to set realistic goals. It can also be an excellent way to measure your progress over time. 

Keep in mind that these measurements are not black and white. This means that you may have a normal BMI ranking but still have too much body fat. Or you may have a high BMI ranking but be at a normal body fat percentage. 

Keeping track of these measurements can help you set and reach your goals. It can also help you get a complete picture of your health. You should use each of these tools to make sense of your body, what change you need to make, and your own goals.