Sharing Session
Topic: Body composition
1
Content page
What is body composition?
Page 3
Differences between Body Mass
Index (BMI) and Body Fat
Percentage (BF%)
Page 4 – 7
Factors that affect body
composition
Page 8 - 9
Why knowing body composition in
important
Page 9
Sample program
Page 10
Conclusion
Page 11
Reference(s)
Page 12 - 13
2
What is body composition?
Body compositions are the component in our body that makes up the total body mass.
Which consist of two parts:
Fat mass:
The total percentage of body mass that comes from fat.
Fat-free mass:
The total percentage of body mass that is not from fat. (e.g. muscles, bone, organ, other
connective tissue.)
Types of body fat
There are two main types of fats in our body:
Subcutaneous fat – Fat beneath the skin, use to protect or absorb shock from any trauma.
Visceral Fat – fat around internal organs, this is a dangerous type of fat.
(image retrieved from: http://www.online-dhaka.com/weight-loss-guide/article/what-is-subcutaneous-fat ) (1)
3
Differences between Body Mass Index (BMI) and Body Fat
Percentage (BF%)
Body Mass Index (BMI)
BMI is the most common and easiest method to determine whether a person is overweight
or underweight. BMI can be measured by using the formula below:
𝐵𝑜𝑑𝑦 𝑀𝑎𝑠𝑠 (𝐾𝐺)
𝐻𝑒𝑖𝑔ℎ𝑡 (𝑚)2
Once got the result from the calculation, the result will be compared according to the
diagram below:
(Image taken from: https://www.healthhub.sg/live-healthy/410/Healthy%20Weight ) (2)
4
Example:
Ah Seng wants to calculate his BMI, he is currently weighing, 70kg and with the height of
1.70m.
As discussed, Ah Seng’s BMI can be calculated with the formula:
70𝑘𝑔
1.70𝑚2
= 25 kg/m2
Compared the result with the diagram, Ah Seng’s BMI puts him at the moderate risk range.
Can BMI really determine whether an individual overweight or underweight?
Body Fat Percentage
Like what had mentioned above (Page 1), body composition is the measurement of
components that makes up our total body mass, which consist of:
-
Total body fat percentage
Bone Mass
Muscle Mass
Total water weight
Body fat can be measured with the following methods (rank in the order of most accurate to
least):
-
Dual Energy X-ray Absorptiometry (DEXA)
DEXA uses low level x-ray to scan
body composition (body fat, muscles,
bone density). This method can only
be done in sports lab or hospital.
-


Pros
Precise
No special
preparation
needed


Cons
Expensive
Requires
experience
radiologist
Skin fold measurement
This method uses a calliper to estimate body fat by pinching the skin thickness at several
points. Which ranges from 3 to 7 sites:
3 sites measurement
Male
Female
Chest
Triceps
Abdomen
Suprailiac
Thigh
Thigh
7 site measurement
Male & Female
Triceps
Chest
Midaxillary
Subscapular
Suprailiac
Abdominal
Thigh
Pros



Inexpensive
Portable
Easy to use


Cons
High technical errors
Not ideal for severe obese or lean
5
-
Hydro densitometry (under water weighing scale)
This method requires the subject to be submerged in water to measure the subject’s density
and the data will be converted to body fat percentage (BF%) using the following formula:
mass
Density (Dbody) = Volume
BF% =
495
𝐷body
– 450
This method can only be done in sports lab or hospital with the equipment.

Pros
More accurate than BMI
Cons



-
Expensive
Uncomfortable (require to forced
expiration and submerge in water
for 30 seconds)
Requires experienced tester
Weighing scale with Bioelectrical Impedance Analysis (BIA)
This method uses a low electrical current that passes through the body to calculate the
resistance to estimate body composition. This can be commonly done by using a
weighing scale with BIA function.
Pros



Quick
Inexpensive
Portable


Cons
Not accurate to certain group of
people (severe obese or lean)
Results may get affect by several
factors (e.g. hydration)
Body fat result can be compared with the table below:
(Image taken from: http://herbalife-sin-ma.blogspot.com/2010/01/calculate-body-mass-index-bmi.html ) (3)
6
Example:
Charlie wants to know his body fat percentage. He got his body fat percentage measured at
a sports clinic through using DEXA.
And the DEXA result shows that Charlie have a body fat percentage of 15%.
Comparing the result with the diagram shown above, Charlie’s body fat percentage is
between fit to healthy range.
Body Mass Index (BMI) VS Body Fat Percentage (BF%)
Ah Seng
Age:
25
Gender:
Male
Weight:
70kg
Height:
1.70m
BMI:
25 kg/m2
BF%:
21%
Table 1. comparing results
Age:
Gender:
Weight:
Height:
BMI:
BF%:
Charlie
25
Male
70kg
1.70m
25 kg/m2
15%
Both subjects have the same age, weight, height, BMI except for body fat percentage. Which
shows that Ah Seng is slightly obese with a BF% of 21%.
This table shows that BMI is not a really a good method to assess an individual body
composition since BMI only take height and weight as consideration and like what had
discussed body composition consist more than just height and weight.
But when it comes to conducting body composition for a large group, BMI will be the best
option since all it need is just height and weight.
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Factors that affects body composition
Although body composition can be changed through diet and exercise, but there are few
factors that individual have no control that is affecting body composition:
Age
Physical activities are lower in older individuals (>50 years old), thus there is a decrease in
total energy expenditure. Resting Metabolic Rate (RMR) are also lower due to decrease of
metabolic active cells and skeletal muscles. (4)
Comparing with healthy younger adults (<40 years old), studies shown that this group have
higher fat free mass (skeletal muscles, bone density) which leads to higher RMR. (5)
Gender
Gender is another determinant of body composition, Basic Metabolic Rate (BMR) of an adult
male is higher than a female of same age and weight (6), studies also shown that men had
higher muscle mass in comparison with women due to differences in physiologically. (7)
Genetics and body types
Studies shows that body composition can be affected by genetics with percentage body fat,
fat mass, fat distribution and fat patterning are characterized through hereditary up to 25%.
(8)
Different body types might play apart in body composition, below are the 3 types of body:
(image taken from: https://attireclub.org/2014/11/29/mens-body-types-traits-fashion-tips/ ) (9)
8
Characteristics of the body types:
-
Ectomorph
long and lean
small body frame
fast metabolism
“hard gainer”
-
Mesomorph
“athletic” body type
Middle of all three
body types
Faster metabolism
compare to
Endomorph but
slower than
Ectomorph
-
-
Endomorph
wide body frame
store body fat easily
compare to other
body type
easier to gain
muscle and fat
Although each body type have different metabolic rate which can affect body fat gains, but
there are more factors that affects metabolism (e.g. muscle mass, age, gender, overall
health). (10)
Hormones
Factors affecting body composition is not just physically but also through hormones, there is
two common hormones that affects body composition in genders:
Leptin
A hormone released from fat cells that helps to regulate energy balance and storage of fats
throughout body. Leptin values in women are two-fold higher than men, (11) which leads to
female have higher fat mass compare to men.
Testosterone
A key hormone for men not just in male reproductive cells but also used to promote
increasing of muscles mass and bone mass. In perspective of biology, men tend to have
higher testosterone compared to women. (12) Since women have lower testosterone, which
also means women tend to have lower muscle mass which result in lower metabolism rate.
Why knowing body composition is important
Body composition is related to health, and individual body fat percentage can determine one
health and longevity. To determine an individual whether he or she is obese, he or she may
go through physical checks using the methods mentioned.
Study shows that excess body fat can increase the risk of health problems example
cardiovascular disease and diabetes, (13) and obesity also associates with high rates of death
in today society. (14) To reduce body fat to a healthy range, individual need to go through a
proper healthy diet (calorie deficit) and exercise at least total of 150 minutes of moderate
physical activities or 75 minutes of high intense physical activities per week. (15)
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Sample program
Knowing that decreasing body fat percentage, individual are recommended to go through a
proper healthy diet (calorie deficit) and exercise at least total of 150 minutes of moderate
physical activities or 75 minutes of high intense physical activities per week.
Resistance training reduce body fat percentage greatly compared to aerobic exercise (16) and
performing aerobic exercise can improve cardiovascular health. (17)
Study shows that a slight calorie deficit of 250 Kcal per day are more sustainable compared
to aggressive calorie deficit. (18)
Intensity of the workout can be gauge using a scale called Rating of Perceived Exertion
(RPE)
RPE Scale
10
9
8
7
6
5
4
3
2
1
Rating
Unable to talk
Talk with difficulties
Able to talk with difficulties
Able to talk with some difficulties
Able to talk with some pause
Able to talk with some pause
Able to talk comfortably
Able to talk comfortably
Able to talk comfortably
Able to talk comfortably
150 minutes of exercise with moderate intensity (RPE 6 – 7)
Monday
Resistance
training for 30
mins
Tuesday
Aerobic training
for 30 mins
Wednesday
Resistance
training for 30
mins
Thursday
Aerobic training
for 30 mins
Friday
Resistance
training for 30
mins
75 minutes of exercise with high intensity (RPE 7 – 9 )
Monday
Resistance
training for 30
mins
Tuesday
Rest
Wednesday
Aerobic training
for 15 mins
Thursday
Rest
Friday
Resistance
training for 30
mins
10
Conclusion
This concluded that BMI are easier to access body composition for large group of
participants whereas body fat percentage are better option for individual and for individual
wanted to know more details about their body composition. Individuals are advised to
maintain a healthy body composition through proper diet and exercise.
11
Reference(s)
1. Types of body fat [Image] (n.d). Retrieved from URL: http://www.online2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
dhaka.com/weight-loss-guide/article/what-is-subcutaneous-fat
Body Mass Index Chart [Image] (n.d). Retrieved from URL :
https://www.healthhub.sg/live-healthy/410/Healthy%20Weight
Calculate body fat percentage [Image] (n.d). Retrieved from URL: http://herbalife-sinma.blogspot.com/2010/01/calculate-body-mass-index-bmi.html
Book Title: Weight Management: State of the Science and Opportunities for military
programs (2004) Retrieved April 30, 2020 from
https://www.ncbi.nlm.nih.gov/books/NBK221834/#top
Xue He., Zishuai Li., Xunhui Tang., Lijung Zhang., Li Wang., Yongjun He., Tianbo
Jin., & Dongya Yuan. (2018) Age and sex-related differences in body composition in
healthy subjects aged 18 to 82 years. Medicine (Baltimore), doi:
10.1097/MD.0000000000011152
Dean Sewell., Philip Watkins., & Murray Griffin (2013). Sport and Exercise Science
an introduction (2nd ed.). New York: Routledge.
Ian Janseen., Steven B. Heymsfield., Zimian Wang., & Robert Ross (2000). Skeletal
muscle mass and distribution in 468 men and women aged 18-88 yr doi:
https://doi.org/10.1152/jappl.2000.89.1.81
Bouchard C., & Perusse L. (1988). Annual Review Nutrition. Retrieved from URL:
https://www.ncbi.nlm.nih.gov/pubmed/3060167
Types of body type [Image] (n.d). Retrieved from URL
https://attireclub.org/2014/11/29/mens-body-types-traits-fashion-tips/
Carmelinda Ruggiero., & Luigi Ferrucci. (2009). The endeavor of high maintenance
homeostasis: Resting metabolic rate and the legacy of longevity. J Gerontol A Biol
Sci Med Sci. doi: 10.1093/gerona/61.5.466
Armellini F. ., Zamboni M. ., & Bosello O. (2000). Hormones and body composition in
humans: clinical studies. Int J Obes Relat Metab Disord. Retrieved form URL:
https://www.ncbi.nlm.nih.gov/pubmed/10997601
Sari M. van Anders., Jeffery Steiger., & Katherine L. Goldey. (2015). Effects
gendered behavior on testosterone in women and men. Proc Natl Acad Sci U S A.,
doi: 10.1073/pnas.1509591112
Therodora W. Elffers., Renée de Mutsert., Hildo J. Lamb., Albert de Roos., Ko
Willems van Dijk., Frits R. Rosendaal., J. Wouter Jukema., & Stella Trompet. (2017)
Body fat distribution, in particular visceral fat, is associated with cardiometabolic risk
factors in obese women. pLoS One., doi: 10.1371/journal.pone.0185403
Mahmoud Abdelaal., Carel W. le Roux., Neil G. Docherty. (2017) Morbidity and
mortality associated with obesity. Ann Transl Med., doi: 10.21037/atm.2017.03.107
American Heart Association Recommendation for Physical Adults and Kids (2018).
Retrieved from https://libguides.scf.edu/c.php?g=847004&p=6077095
Clemens Drenowatz., Gregory A. Hand., Michael Sagner., Robin P. Shook.,
Stephanie Burgess., & Steven N. Blair. (2016) The prospective association between
different type of exercise and body composition. Med Sci Sports Exerc., doi:
10.1249/MSS.0000000000000701
Kesley Pinckcard., Kedryn K. Baskin., & Kristin I. Stanford. (2019). Effects of
exercise to improve cardiovascular health. Front Cardiovasc Med., doi:
10.3389/fcvm.2019.00069
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18. Diana M. Thomas., Corby K. Martin., Steven Lettieri., Carl Bredlau., Kathryn Kaiser.,
Timothy Church., Claude Bouchard., & Steven B. Heymsfield. (2013). Can a weight
loss of one pound a week achieved with a 3,500 kcal deficit? Commentary on a
commonly accepted rule. Int J Obes (Lond)., doi: 10.1038/ijo.2013.51
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