SEHS Topic 4.3 Continued – The Fundamentals of biomechanics – Part II

Factors affecting the location of the total body COG

Cont’d Sex: Since the distribution of body mass differ from males to females the COG will be located higher in males than in females. Addition to subtractions of weight in some parts of the body: Addition of weight: carrying weight will move the COG towards the location of load. E.g. carrying a weight above the head will raise it upwards. Carrying a weight behind the trunk will move the COG backwards.

COG Cont’d

COG Cont’d: Explain that a change in body position during sporting activities can change the position of the C.O.M./C.O.G The location of the center of gravity can be outside the human body during activities depending on relationship of body segments. The change in position of limbs from the anatomical position ( when the arrangement of the body shifts), e.g. raising both arms will raise the COG.

Additional Images – COG: Where is it?

Distinguish between first, second and third class levers First off…..What are levers? Definitions Lever: Rigid bar that turns about an axis of rotation or a fulcrum (A) Motive Force (F): effort or exertion applied to cause movement against resistance or weight (a.k.a. Effort) Resistive Force (R): opposes motive force (a.k.a. Load)

Distinguish between first, second and third class levers Cont’d

Label anatomical representations of levers