Biomechanics Flashcards
What are the main functions of a lever system?
- Generate a muscular force to overcome a load
2. Increase the speed of a given movement
Define levers?
The CO-ORDINATION of muscles and bones to create movement.
1st Class Lever Key Points?
(“see-saw”)
The fulcrum is in the middle of the joint with the effort AND the load pushing downwards.
Found at the neck/cranium.
Good for average speed and movement
EG: A player nodding their head in agreement with an official
–Fulcrum= joint between the head and vertebrae
–Load= the weight /resistance of the cranium
–Effort= muscles attaching to the cranium eg: trapezius.
2nd Class Lever Key points?
(“wheel- barrow lever”)
The load is in the middle pushing down and the effort is pushing upwards= a Mechanical
Advantage
EG: A diver standing on their tip-toes before dismounting the board.
–Fulcrum= Metatarsals joint
–Load= Weight of body
–Effort= Gastrocnemius and soleus
3rd Class Lever Key Points?
The effort can be seen within the fulcrum and the load pushing upwards, the load pushes downwards.
=a Mechanical Disadvantage
EG: The flexion stage of a bicep curl.
–Fulcrum= hinge joint between radius and humorous
– Load= weight of forearm and dumbbell
–Effort= bicep muscle when contracting
Critically evaluate a second class lever?
+mechanical advantage so can move large loads with relatively small effort (MA) due to longer effort arm
-but at the expense of speed and acceleration as only moved through a small ROM so acceleration is reduced
Critically evaluate a third class lever?
+load is moved through a greater range of motion creating greater velocity and increasing acceleration
-but they require large amounts of effort to be generated to lift small loads (MD)
How do you calculate mechanical advantage ?
MA= Effort arm
Load arm
What are some examples of modern technology that benefits sport?
- Track cyclists are benefited by streamlining helmets, Lycra clothing and modified positions.
- Shin pads, gum shields and football spikes.
- Entertainment increases through TMO and Hawk Eye.
Define limb kinematics?
The study of motion in relation to speed and time.
Limb Kinematics: USE
Limb Kinematics: OPTERMISING PERFORMANCE
(Long distance Runners and Sprinters)
Use reflective markers on appropriate anatomical positions. 3D OPTICAL MOTION records an athlete performing an action to calculate efficiency of movement.
Data produced can be used to improve specific techniques.
Limb Kinematics: EVALUATE
+ can focus on specific techniques eg: golf swing
+not dependant on environment due to lab conditions
- very expensive, needs to be undergone by professionals
- specialised facilities and therefore not “natural movements”
Force Plates: USE
Force Plates: OPTERMISING PERFORMACE
(High Jumpers)
A force plate is inserted into the ground and used to allow analysis of PATTERNS OF FORCE made by the foot striking the floor.
Athletes run, jump and balance on plates
Tells the precise way the foot is placed and allows you to see of foot posture change is needed.
Force Plates: EVLUATE
+can help balance, gait and physiotherapy rehabilitation
+accurate and immediate
- Specialist, expensive
- Doesn’t replicate natural position of high jumping.
Wind Tunnels: USE
Wind Tunnels: OPTERMISING PERFORMANCE
(Track Cyclists, F1 Racers)
A steel framed building containing large fans where artificial wind is produced. Used to develop the Drag Deduction Scheme and increase STREAMIING
Can help: Type of clothing Width of handle bars Riding posture and hand position on bars
