Home / Bodybuilding Tracking Program / Skinfold Measurements

How To Take Skinfold Measurements and Calculate Body Fat Percentage

The first thing you will need to take skinfold measurements are skinfold calipers (body fat calipers). There are fancy models out there, but in my opinion you are just fine with the cheaper models.

AccuFitness (Accu-Measure) is the leading supplier and offer a simple little plastic caliper called the Fitness 3000. It is easy to use with a nice sliding scale and click feature to let you know when to get your reading (excellent for improving the reliability of the measurement). A small step up is the FatTrack Gold which is the digital version and makes getting your skinfold measurements somewhat easier. It will automatically figure your bodyfat percentage based on the 3-site equations below.

With a little shopping time, you should be able to find the Fitness 3000 for less than $15 and the FatTrack Gold for less than $25. Also, keep in mind that you want to complete your body composition tracking program with body tape measurements. For this, you need a flexible tape and you will find it easy to get a Accufitness Myotape (an excellent product) thrown in with your skinfold caliper purchase (FatTrack Gold Package).

The Skinfold Sites

If you don't have a partner and are not freakishly flexible, you will not be able to get to all the 7 skinfold sites listed below and shown to the right. That's okay, men can just do 3 sites - chest, abdominal, and thigh. Women can also get a good body fat estimation with three sites - tricep, suprailiac, and thigh - but the tricep will be tough without a partner.

Chest - For men, get a diagonal pinch half way between the armpit and the nipple. Women need a diagonal pinch 1/3 of the way from the arm pit to the nipple.

Midaxillary - A vertical pinch on the midaxillary line which runs directly down from the center of the armpit. Raise your arm above your head and have your partner get these skinfold measurements just below the level of your nipple.

Subprailiac - A diagonal pinch just above the front forward protrusion of the hip bone.

Abdominal - A vertical pinch about one inch from your belly button.

Thigh - A vertical pinch halfway between the knee and top of the thigh.

Tricep - A vertical pinch halfway between the shoulder and the elbow.

Subscapular - A diagonal pinch directly below the shoulder blade.

 

 

Skinfold Measurement Taking Tips

• Take your skinfold measurements while standing.
  
  
• Take all skinfold measurements on the same side of the body. Preferably the right side.
  
  
• Pinch between your forefinger and thumb. Pinch deep enough to get the fat (you are looking for a double-thick pinch of skin) but not so deep that you start pulling muscle up. Pulling muscle up is pretty much impossible so don't let it concern you all that much. With the skinfold in hand, you need to pinch hard to get the water out, hard enough that you cause minor discomfort.
  
  
• Place the body fat calipers less than 1/2 inch from your pinch, midway between the crest and the base.
  
  
• For each of the skinfold sites, take three measurements and use the average of those three. But don't take the three measurements consecutively, instead run through all the sites three times. This will allow the skin to regroup between skinfold measurements. It will also help you develop some consistency.
  

Consistency is the key. If you are having a friend take your measurements, which is the ideal thing to do, have that same friend take your skinfold measurements every time. If you have different people take your measurements, expect the results to be all over the place and basically useless.

Calculating Your
Body Fat Percentage

To get an overall number to use as your body fat percentage, you will need to plug your numbers into a formula. With your skinfold measurements in hand, check out the Guide's online body fat percentage calculator. It will not only give you your body fat percentage but your lean body mass as well.

The most commonly used equations for body fat calculations based on skinfold measurements are based on Jackson-Pollock's equation for bone density and Siri's formula to get body fat percentage from that:

Body Fat Percentage Man:

Seven Skinfold Sites (all 7 sites from above, SUM7 is the sum of all the measurements in mm)

Bone Density =	1.112 - (0.00043499 * SUM7) + (0.00000055 * SUM7²) - (0.00028826 * Age)
Body Fat Percentage =	[(4.95/Bone Density) - 4.5] 100

 

Three Skinfold Sites (Chest, Abdominal, and Thigh sites from above, SUM3 is the sum of these sites in mm)

Bone Density =	1.1093800 - (0.0008267 * SUM3) + (0.0000016 * SUM3²) - (0.0002574 * Age)
Body Fat Percentage =	[(4.95/Bone Density) - 4.5] 100

 

Body Fat Percentage Woman:

Seven Skinfold Sites (all 7 sites from above, SUM7 is the sum of all the measurements in mm)

Bone Density =	1.097 - (0.00046971 * SUM7) + (0.00000056 * SUM7²) - (0.00012828 * AGE)
Body Fat Percentage =	[(4.95/Bone Density) - 4.5] 100

 

Three Skinfold Sites (Tricep, Suprailiac, and Thigh sites from above, SUM3 is the some of these three sites in mm)

Bone Density =	1.0994921 - (0.0009929 * SUM3) + (0.0000023 * SUM3²) - (0.0001392 * AGE)
Body Fat Percentage =	[(4.95/Bone Density) - 4.5] 100

If these equations look like a fun Saturday afternoon to you, have at them. Otherwise just go to the Body Fat Calculator.

Or better yet, get a software program that will do the calculations and keep track of your results for you. Doing so will be a wise investment (several of the top bodybuilding programs have good ones as part of their package and there are others available seperately).

The tough part is the skinfold measurements...

With your body fat percentage in hand, you are only a small and simple step away from getting your Lean Body Mass (LBM) number (and the calculator will give that to you as well).

LBM is based on your body fat percentage and your weight. Multiply your body fat percentage by your weight and you have a quick estimate of how many pounds of fat you are toting around. Subtract that number from your weight and you have your LBM.

Check out the Lean Body Mass (LBM) page for more on the importance of this number and how to use it to help guide your program.

 

Related Articles

All The Bodybuilding Program Tracking Articles

	Body Fat Percentage Calculator The Guide's online calculator that calculates both your body fat percentage and lean body mass.
	How To Track Your Bodybuilding Training Program - An overview of how to do it and the things you need to track..
	Body Fat Percentages: Understanding, Calculating and Using Your Number - The many methods available for estimating your body fat percentage.
	How To Take Body Tape Measurements Suggested sites to regularly get tape measurements from and how to take them.
	The Value of Following a Complete Program A solid program will produce considerably better results than the typical "cafeteria approach."
	Monitoring Your Weight Gain Program From Anthony Ellis, how to monitor your program and how it can benefit you.