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Cutting Edge Personal TrainingApril 12, 2021

the ten best (and worst) ways to assess body composition

Assessment tools give us feedback, showing us the effects of what we've been doing. This allows us to analyze whether our fitness and nutrition are on the right track.

The only problem...some assessment tools SUCK.

On the flip side, the assessment tools that don't suck are often impractical, expensive, or hard to find.

That's where today's feature article comes in. Let's look at which assessment tools are crap, which are decent, and how to use them for the best results. Here they are in ranking order, from worst to first.

Bio-Impedance.jpg10. BIO-IMPEDANCE

Bioelectrical impedance analysis (BIA), in theory, measures body fat and muscle mass via electrical currents that travel from the machine through your body. These are the things at least one of your personal trainers has made you hold between both hands, or stand on...or both hold and stand on. These things are known for giving hilariously inconsistent readings.

Where It Falls Short

The same person can get different readings on different devices, or even the same device during different times of the day. While doing my last cut, I was said to be 16 percent body fat and 11 percent body fat on the same exact day. They're just horribly inconsistent.

How to Use It for Best Results


Overall Grade: F


While getting to see how much you weigh on occasion can be helpful for those who are very overweight, those who are very underweight, and those who don't care about building muscle, for those of us who intentionally build muscle, it needs to be taken somewhat with a grain of salt. The power it has over people's minds is surreal. It's just a dang tool. You shouldn't hate it or be a slave to it.

Where It Falls Short

It doesn't differentiate between lean body mass, fat, water, or waste (aka - poop). If you're someone who carries a good amount of muscle, the number on the scale can easily be manipulated by increasing or decreasing muscle glycogen (stored energy within the muscle cells). I've had many a client do this on accident and then beat themselves up when they're heavier or lighter than they want to be. Another thing that many women reading this will relate to, scale weight can be higher during menstrual phases because of water retention.

How to Use It for Best Results

People who use the scale with great success generally see their weight as a byproduct of their habits and not the be-all, end-all goal. Give yourself a range instead of a single number (For example, I feel my best in a range of 182-186).

Overall Grade: C

8. BMI

The BMI (body mass index) is a calculation or chart that shows whether you're underweight, overweight, or normal. A BMI between 18.5 and 24.9 is said to be normal. Of course, there are outliers. Anyone with a good amount of muscle can be incorrectly categorized as overweight or obese by the BMI. But they know this and are smart enough to dismiss this calculation for themselves. Sometimes you're overweight on the BMI chart because you're actually overweight...even if you have a significant amount of muscle.

Where It Falls Short

I've already touched upon that people with lots of muscle can be incorrectly categorized as overweight. But it can work the other way, too. There are many people in the elderly population who have lost a lot of muscle with age that will be told they are in the "normal" range, even though they are carrying a lot of fat and not in good shape. In fact, anyone can be categorized as normal weight but still have an unhealthy (even dangerous) amount of visceral body fat. This is particularly true if you're kind of skinny everywhere but the belly.

How to Use It for Best Results

Recognize whether you're truly an outlier (a big skeletal frame with a lot of muscle on top of it).

Overall Grade: C+


If your main goal is to avoid heart disease and type 2 diabetes, this is the best assessment tool for you. The National Heart, Lung, and Blood Institute (NIH) says "If most of your fat is around your waist rather than at your hips, you're at a higher risk for heart disease and type 2 diabetes. This risk goes up with a waist size that is greater than 35 inches for women or greater than 40 inches for men." PS - your pants size is not your waist size. Don't fool yourself.

Where They Fall Short

It won't tell you crap about muscle mass, and you can't get your body fat percentage from it. There's a bit of potential for user error. Like I eluded to above, some of you will think your waist size is the same as the waistband on your jeans. It's not. Trust me.

How to Use Them for Best Results

Find your belly button and then measure the circumference of your waist right there. Check on this number from time to time. Do it more frequently if it's been anywhere around those metrics put forth by the NIH.

Overall Grade: B-

Skin-Caliper.jpg6. SKIN CALIPERS

Here we have the skinfold test. The person administering it pinches your fat at specific places on the body, then plugs those numbers into an equation to determine your body fat percentage.

There are many versions (3-site, 4-site, 7-site, 9-site). It's assumed that the more sites pinched, the more accurate the body fat estimation.

Where it falls short

This is only as good as the person doing the pinching, making some room for user error. They can grab a lot or a little. They can pinch the calipers harder or apply less pressure (higher-quality calipers minimize user error, but they can run up to 400 bucks). And they can also take measurements in imprecise locations.

How to Use Them for Best Results

It's best to have the same person administer it every time. If they're experienced, then they'll do it the same exact way. Even if the measurements are imprecise, you can at least see how you're trending over time. You could also use it to simply track the fat in specific areas.

Overall Grade: B


This is a contraption you sit in that measures air displacement to determine what portion of your body is fat mass versus lean mass. It's said to be about as accurate as DEXA if you're just wanting to measure lean mass compared to fat mass, but it won't give you any specific info on bone density.

Where It Falls Short

It can get pricey if you're wanting to test yourself regularly, and if you're able to find a place that offers this service (it may be subject to closing for pandemics). There's been some research showing its inaccuracy. In one study, the Bod Pod overestimated the amount of fat on lean participants by up to 13 percent and underestimated the amount of fat on heavier participants by up to almost 9 percent. The participants who were closest to a healthy BMI got fairly accurate results.

How to Use It for Best Results

Use it if you can, but remember that even the most respected methods can be inaccurate. And just like the other precise but expensive methods, it may be a little impractical for regular use.

Overall Grade: B


You could obsess over the numbers all you want, but the big question is, do you look like you workout? Do you appear generally lean and fit? The mirror answers those questions.

It's one of the most common-sense tools we have. When you're lean enough, you can see relatively quickly how a training method or dietary approach affects your body composition.

Where It Falls Short

Day-to-day changes may be so gradual that you may not realize when you're improving (or slowly going the other way and getting out of shape). Water retention can also steal your joy. Same with anything that causes bloat/stomach distension.

How to Use It for Best Results

Be objective. That means assessing your physique more like a scientist, not a grade school bully or a woke Instagram influencer. Use it to analyze what you've been doing in the kitchen and gym. Remember to account for time of day (or phase of month for women), behaviors you've picked up recently – good or bad – and how your digestion is doing.

Overall Grade: B+


The fit of your best-fitting jeans will tell you a lot.

Where They Fall Short

Those who've disproportionately accumulated a lot of visceral fat may not get the info they need. This is likely to happen if your belly sits above your waistband. Also...washing and drying them may cause shrinkage. Conversely, jeans loosen up gradually with wear. So if your favorite pair is getting bigger over the years, you might assume you're getting leaner when you're not.

How to Use Them for Best Results

This could easily be an everyday assessment that you can do on the fly. Just be aware that tighter jeans could be from spending time on the gainz-train. Find a pair that hug your hips, waist, and thighs without squeezing the ever-loving hell out of your body. Don't get "stretch" jeans. They will tell you lies. And try not to put them in the dryer, like I do.

Overall Grade: A-


It's considered the "gold standard" because of its accuracy. You basically get weighed underwater to determine what portion of your body is fat mass versus fat-free mass. Fat-free mass (bone, muscle) has a greater density than water. Fat mass has a lower density than water; it floats. So when you're underwater, the more lean mass you have, the more you'll weigh.

Where It Falls Short

It's inaccessible for most. 

How to Use It for Best Results

Do it if you can, but don't depend on it as a regular assessment tool unless you have connections.

Overall Grade: A

DEXA-2.jpg1. DEXA

This is the dual X-ray absorptiometry scan and it can accurately analyze your fat, muscle, and bone density.

Where It Falls Short

You can't buy one for the home or casually use one at your gym. And it's somewhat inaccessible for the average person (you're lucky if you can find a university or medical center where assessments are offered).

How to Use It for Best Results

If you can find one nearby and don't mind shelling out some dough, I highly recommend it.

Overall Grade: A

Final Thoughts

All of these tools have shortcomings, but picking out a few, keeping them in perspective, and using them fairly regularly should give you as much info as anyone would need.

Sleep for fat loss

If you’re not getting adequate rest (close to 8 hours each night) then you’re more likely to be hungry, overeat, and put on fat.

How does this work? Something like this…

If you’re tired, your brain will want a burst of dopamine. This causes us to opt for fast (fattening) foods. Not to mention, who feels like cooking a healthy meal when they are tired?!?

This very same lack of energy will also likely cause you to skip the gym. 

On top of of all that, sleep deprivation causes your cortisol levels to rise and your metabolism to slow down. Just in case you’ve not heard...that is not something you want when trying to shape up.

Quick & Creamy Chicken Soup

​By using flavorful ingredients, like roasted red bell peppers and white bean hummus, this soup will taste like you slaved over it all afternoon– but it takes less than 20 minutes to throw together. 

This recipe is also a great way to fit some quinoa into your diet. Quinoa is a protein-packed seed that is considered a “super food”. It’s the only grain that is a complete protein, containing all 9 essential amino acids, and is gluten free.

Courtesy of

What you need
Servings: 5

1 cup roasted red bell peppers
3/4 cup white bean hummus
2 cups chicken stock
1/2 cup cooked quinoa
1 cup shredded rotisserie chicken
dash salt and pepper
2 Tablespoons parsley, chopped


1. Take 1/4 cup of the roasted red peppers, slice into strips and set aside.

2. Place the remaining red peppers in a blender along with the hummus and chicken stock. Blend until smooth.

3. Transfer to a medium saucepan. Add the quinoa and chicken. Season with salt and pepper.

4. Bring to a boil.

5. Ladle the soup into bowls and garnish with the slices of red pepper and chopped parsley.

One serving equals: 248 calories, 11g fat, 644mg sodium, 14g carbohydrate, 3g fiber, and 20g protein

Nashville Personal Trainer, Jim Cipriani
James Cipriani - CPT
  • Master Level Personal Trainer
  • Leader in the Fitness Industry for over 20 Years
  • Over 30,000 Personal Training Sessions Completed
  • Countless Success Stories, and
  • YOUR Fitness and Nutrition Coach in Nashville, TN!

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Jim's Cutting Edge Exercise Success Guidelines...Are YOU Meeting Them?
If you're not meeting your weight loss goals, of course how you eat is one of the first fixes you should be looking at. of the EASIEST things to change is your exercise variable.

Specifically...Frequency AND Consistency.

In a week, at a MINIMUM, EVERYONE should be getting in 4 Days combined of Resistance Training and/or Interval Cardio Work.

That means, if you work with me...

1 x Week, you should be adding:
- 1 more Resistance Training day on your own plus 2 Interval Cardio Sessions. OR...
- 2 more Resistance Days on your own plus 1 Interval Cardio Sessions.

2 x Week, you should be adding:
- 2 Interval Cardio Sessions. OR...
- 1 More Resistance Training Day done on your own PLUS 1 Interval Cardio Day.

3 x Week, you should be adding:
- 1 Interval Cardio Day.

On top of this, as an added BONUS, EVERYONE would benefit from adding 1-2 Steady-State Cardio Sessions in a week. Go for a walk. A jog. Hop on a bike. Whatever you choose, just get moving at a steady pace and do it for 40-60 minutes. Of course, this will be depending on the time availability in your personal schedule AND your desire to get results.

Are you meeting the Cutting Edge Exercise Guidelines?