arthur stewart
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Somatotype. Arthur Stewart. Mandy Plumb Department of Orthopaedics. Somatotype. Definition. Somatotype is a physique classification system which recognises a body shape category, which necessarily falls between pre-determined end limits. - PowerPoint PPT PresentationTRANSCRIPT
Arthur StewartSomatotype
Mandy PlumbDepartment of Orthopaedics
Definition
Somatotype is a physique classification system which recognises a body shape category, which necessarily falls
between pre-determined end limits.
It is defined as a quantified expression and description of the present morphological conformation of a person.
It is independent of size, age and gender.
Somatotype
•Somatotype is a three figure reference which characterises physique and body shape.
•It comprises values, originally proposed on a 7-point scale, which summarise the physique, and can be plotted on the tri-polar somatochart.
Somatotype
•Endomorphy
•Mesomorphy
•Ectomorphy
Average value
4
4
4
5
5
5
6
6
6
3
3
3
2
2
2
lean fat
muscularslender
lightheavy
Somatotype Components
Originally proposed as a genotypic morphology rating on a 7 point scale by Sheldon (1940), drawing from earlier work of Kretschmer (1921) who classified three ‘poles’ to represent extreme physique variation, and Viola (1933) which related dimensions of the thorax, trunk and limbs to a ‘normotype’
Partly influenced by an alternative methodology from Parnell (1954), Heath and Carter (1967) introduced a three numeral rating somatotype which has become the most universally applied, which involved a photoscopic and anthropometric method, later to be revised in 1990.
HistorySomatotype
• Photoscopic• Anthropometric*
– somatotype rating form– computer-calculated
• Combined– the criterion measure
• Stadiometer• Weighing scale• Bone caliper• Skin caliper• Anthropometric tape
Methods *Equipment required
Somatotype Assessment
Somatotype Rating Form
Somatochart•Central•Endomorph•Mesomorph•Ectomorph
• Endomorphy– Roundness or fatness, based on 3
skinfolds Independent of size• MesomorphyMesomorphy
– Musculo-skeletal robustness, based on elbow & knee breadths, and corrected girths of calf and upper arm
• EctomorphyEctomorphy– Relative fragility, based on height
and weight
• Derived on 10 measurements
• Independent of size• Descriptor of shape• Assumes proportionality of
size, development and symmetry
• Only relative data on composition
(Heath & Carter, 1967)
Anthropometric Somatotype Assessment
Total mass (kg)Stature (cm)Upper arm circumference
(cm)Max. Calf circumference
(cm)Femur breadth (cm)Humerus breadth (cm)
Triceps skinfold (mm)Subscapular skinfold
(mm)Supraspinale skinfold
(mm)Medial calf skinfold (mm)
Measurements on the Right; Larger girths in the case of Left handed subjects; mean of 2 or median of 3.
Measurements Required
calculation
Add the skinfolds at the triceps, subscapular and supraspinale sites
Multiply this sum by 170.18 / height
This total (in mm) is “X” in the following calculation:
Endomorphy = -0.7182 + 0.145X - 0.00068X2 + 0.0000014X3
Endomorphy
Record height (H), humerus breadth (HB) and femur breadth (FB), max calf girth and max upper arm girth, with the arm flexed to 45º and tensed.
Calculate corrected arm (AG) and calf girth (CG) by subtracting triceps and medial calf skinfolds from the respective girths.
Substitute these values in the following equation:
Mesomorphy = 0.858HB + 0.601FB + 0.188AG + 0.161CG - 0.131H + 4.5
Mesomorphycalculation
Record height in cm and weight in kg
Divide the height by the cube root of weight to calculate the reciprocal of the ponderal index or RPI. The magnitude of the RPI determines which formula is used to calculate ectomorphy.
If RPI > 40.74, Ectomorphy = 0.732RPI - 28.58
If 39.65 < RPI < 40.74, Ectomorphy = 0.463RPI - 17.615
If RPI < 39.65, Ectomorphy = 0.5
calculation
Ectomorphy
Rounding
• From equations - round decimal to one decimal place eg. 3.1-4.7-1.4
• For general description, plotting and category boundaries, round to the nearest half unit eg. 3-4-1
• Rating form are in nearest half units
Somatotype Attitudinal DistanceThe distance between any two somatopoints (in 3D space)- calculated in component units
SAD A,B = [(endoA-endoB)2 + (mesoA - mesoB) 2 + (ectoA - ectoB) 2 ]0.5
where A and B are two somatotypes
Somatotype Attitudinal MeanThe average 3D distance between all somatoplots and their mean
Cardiac healthLow energy cost of locomotionpower:weight ratioInjury protection via diminished forces
Absolute strength, injury resistance, hypothermia resistance, positive self image
Absolute mass for blocking sports; Hypothermia resistance, floatation
Physique advantages
Lack of upper body strength; risk of diminished self image
Power at expense of endurance; poor heat dissipation; exercise can become obsessive in bodybuilders
Low power: weight; high energy cost of locomotion; impaired heat dissipation; cardiac risk factors; low self esteem
Physique disadvantages
Endomorphy
Ectom
orph
y
Mesomorphy
Data from Stewart & Hannan, (2000)
Somatotypes of 106 male athletes
Sumo wrestlers
High jumpers
Discus throwers
400m runners
Early training
Performance peak
Athletes’ physiques evolve according to training status and
periodisation. Variation in physique (i.e. SAM) reduces as competitive standard
increases, as the athletes become
increasingly selected
Somatotype Convergence
Road racing cyclists’ data from Stewart & Hannan (2000)
Somatotype comparison in cyclistsReference: Anthropometrica
• Each component independently affects performance in most sports
• Talent identification for sporting potential of individuals• Tool for matching individuals with sports which they may
have advantages for• Tool for determining training goals and outcomes• Affects body image and self esteem
The relevance of somatotype in sport
Summary
References
Anthropometrica: Norton, K & Olds, T. (Eds) (1996) University of New South Wales Press
Carter J.E.L. and Heath, B.H. (1990). Somatotyping: Development and applications. Cambridge, UK, Cambridge University Press.
Eston, R. & Reilly, T. (Eds) (2001) Kinanthropometry and exercise physiology lab manual, volume 1. London: Routledge