Body composition is extremely important for our overall health. When we get obese or overweight it opens us up to a plethora of diseases such as diabetes, heart disease and immune issues not to mention over time it destroys our joints from carrying excess weight. Body composition is extremely important for athletes at all levels because being overweight has significant consequences on athletic performance. Just a 2% increase in body fat can dramatically impede and athletes’ performance.
So, as Personal Trainers, it’s really important to be able to track fluctuations in fat free mass. According to the Minnesota starvation study, if an individual loses too much fat free mass while losing weight ie. muscle, the body will experience something called Hyperphagia: https://my.clevelandclinic.org/health/symptoms/24637-polyphagia-hyperphagia, which is an extreme hunger response that’s out of balance with our metabolic use. This causes the person to experience a desire for extreme “binge” eating. It’s theorized that once the Fat Free Mass or muscle is gained back the hyperphagic condition will cease. It’s speculated that Muscle tissue is responsible for individuals to maintain what is known as the “set point” in the weight loss and Personal Training industry.
So it’s safe to say that body composition is an extremely important aspect when beginning to lose weight- correctly. There are several methods of measuring body fat that Personal Trainers use but it’s important to note that all of these methods that I will touch on are estimates at best because it’s hard to access a living organism that consists of muscle, bone and water etc. So most methods have a margin of error. Below are the most common methods I will touch on as a personal trainer and where you as a consumer can find one of these methods. Below is an image of the classifications of body fat levels. This chart will give you an idea of a healthy body fat percentages according to age and gender. It’s also important to note that here on my personal training website, I have a body fat calculator that you can use to get a rough estimate of what percentage you may have. All you need is a flexible tape measure and a few basic circumference measurements. Here is a link to my Personal Training calculator page. https://personaltrainersandiego.com/estimating-body-fat-calculator/
TYPES OF MEASUREMENT:
- Circumference measurements, which can be done using a tape measure or more advanced techniques such as a styku. In Styku’s case, circumference measurements of the body are captured in Styku’s 3D body scan and are applied to an equation that Styku derived using hundreds of subjects scanned in a DEXA machine. DEXA stands for Dual-Energy X-ray Absorptiometry, and the device is an X-ray machine you lay down on as X-rays are passed over your body. DXA scans are considered the gold standard in body fat analysis. Most circumferences measurements using a tape measure or body fat caliper are entered into a formula that uses age, height, weight, gender and calipers or tape measure values and computes an individual’s body fat. The problem is there are over 100 formulas for this. The Styku is a very accurate assessment tool in the circumference method and if you would like to get one done, many gyms have them now.
As I stated earlier these formulas are estimates and most circumference formulas have and margin of error at 3-5%. The software I prefer when using calipers to calculate my personal training clients body fat % is one owned by Linear.
See the link: http://www.linear-software.com/online.html - The next one is called a BodPod, which operates off of Air Displacement Plethysmography. It is similar to under water hydrostatic weighing but employs air as a medium instead of water. There is a margin of 3-4%. BodPod is available in most cities via a google search. No prescription is needed. If you reside in San Diego, check out this link: https://www.fitnescity.com/bod-pod-test-in-san-diego-ca
- Hydrodensitometry or better known as hydrostatic weighing. At one time this was the gold standard for calculating body fat percent. The problem is it is a large piece of equipment filled with a large volume of water. The participant sits on a chair in the tank and is then completely submerged into water. It works off the concept that fat floats. So the heavier you are in water the lower the body fat percent. It has a 3-5% margin of error. If you live in San Diego there is a company I have used before called “Get Tanked”. I had a great experience using them and I recommend them if you are interested in this form of testing. What’s great is that he has a mobile unit and operates out of truck, so he can come to you. Check out: https://www.bodyfattestsandiego.com/
- Next is the Bioelectrical Impedance Analysis or BIA. It’s based off the theory that fat mass does not conduct electricity, while lean mass is a very good conductor. By measuring the rate of travel of the electrical impulse, one’s body fat percentage can be estimated. The problem is there is a large degree of variability between units sold especially the hand-held ones and the ones on a scale. They are not accurate and have a large degree of variability, up to 5% or more in some cases. The two point BIA machines calculate fat based on a “Prediction calculation” which is not accurate and like I said-a prediction. However, there is a unit called the In Body 570, which uses a four-point system of contact instead of a two point like the hands only or feet only. The In Body 570 is expensive but many personal training facilities have them now and they are an accurate means of assessing body composition. The best thing is that it can assess body water which can be paired with a DXA scan result to give the data 4 compartments of measurement, which is a the most accurate estimator of body fat %.
- Lastly is the DXA scan or Dexa as it is commonly known. This advanced form of x-ray technology was first used to detect osteoporosis to determine a person’s level of bone loss. This is now the gold standard for measuring body fat percentage in the personal training industry as well as other weight loss specialists. It is even more accurate when it findings are combined with the assessed body water from a bioimpedance scan (BIA) in category four above. In an article written by Abbie Smith Ryan- In the 2017 international Journal of Sports Nutrition, Smith -Ryan explains how the four components of measurement that we obtain from the two tests combined being Bone, Lean Body Mass, Fat Mass and water, can yield the most accurate body fat assessment.
In closing, it is important to remember when trying to lose weight or body fat that the individual or athlete loses weight slowly which will minimize muscle wasting. Too little calories will cause muscle to be used as energy and in turn could trigger hyperphagia which is a nightmare if you are trying to drop fat weight with a ravenous appetite.
The following will give you an idea of what I do as a personal trainer and former competitive bodybuilder and fitness model, to keep my body fat in check. What I first do is determine my maintenance calories. On my personal training website here, I have a really cool calculator you are free to use that will give you an idea of what your body fat percentage may be. Go to: https://personaltrainersandiego.com/estimating-daily-calories/
Once I have determined my maintenance calories, I use a free App called MyFitnessPal and a must have if you want to be technical about losing weight. Most of all it keeps you accountable so you can see in real time when you need to put the fork down.
I then log my “maintenance” calories for four days to see what my weight does. At the end of four days if I lose 3 or more pounds (and you are NOT obese) my calories are too low and I need to raise them 250 a day for four days again. If my scenario is that after four days I don’t lose weight, I subtract 250 kcals a day and see what happens after four more days.
Once I find a caloric range where I lose 1-2lbs a week, I then incorporate a caloric fluctuation with a weekly total calorie goal. Allowing me to eat more some days and less others.
As far as my macro-nutrients go, I eat (1) gram of protein per pound of body weight. If I weigh 200 lbs. I eat 200 grams, which is 800 calories. If my total daily calories are 3000, the remaining 2200 calories will consist of 80% carbs and 20% fat. I can’t stress how important strength training is when losing weight. By strength training we maintain or even gain muscle mass which helps inhibit Hyperphagia.
Thanks- John
