Chapter 3 Flashcards
Levers
A rigid bar that turns about an axis of rotation
1st Class Lever
Axis is between force and resistance (F-A-R)
**Designed for balanced movements
Ex: Triceps in overhead elbow extension
2nd Class Lever
Resistance is between axis and force (A-R-F)
MAF>MRF
**Designed to produce force movements
Ex: Wheelbarrow
3rd Class Lever
Force is between axis and resistance (A-F-R)
MAF<MRF
**Designed to produce speed/range of motion
–Most levers in body are this class
Ex: Catapult
Ex: Biceps in bicep curl
Mechanical Advantage (MA)
MA= MAF/MRF
MA=1 lever alters movement direction but does nothing to magnify either effort or resistance
MA>1 torque is magnified by effort force
MA<1 much greater force required to overcome resistance most skeletal muscles operate here
Muscle Cross-Sectional Area
Force is related to cross-sectional area, not volume.
Greater cross-section = greater force produced
Muscle Fiber Arrangement
Pennate muscles have fibers that align obliquely with tendons – similar to a feather
Unipennate: Tibialis Anterior
Bipennate: Rectus Femoris
Multipennate: Deltoid
Muscle Length
Resting muscle will be able to generate most amount of force when compared to a contracted or stretched muscle.
Body Size
Pound for pound
150 lb girl lifting 150 lb is stronger than a 250 lb girl lifting 150 lb.
Relative strength
Anthropometry
Science of measurement of man
Bone Density
1.8
Muscle Density
1.1
Fat Density
.9
Ponderal Index=
(height inches) ÷ (weight lbs)1/3
Density=
0.69 + 0.0297*(ponderal index)
Ectomorph
Tall, skinny, long distance
Ex: Marathon Runners
Mesomorph
Normal body type
Average
Ex: Swimmers
Endomorphs
Large body build
Ex: Power Lifters
Neuroanatomy
Where nerve tissue and nervous system components are in the body
Ex: axons, soma, dendrites
Neurophysiology
What the nerve tissue and nervous system does in the body
Neurobiology
What the nerve tissue and nervous system is made of
Neurology
Study of and clinical/medical application of the nervous system and nerve tissue
Functions of the Nervous System
- Sensory Input
- Integration (sensation –> response)
- Control of muscles and glands
- Homeostasis (stimulation, inhibition)
- Mental Activity (consciousness, emotion)
Central Nervous System (CNS)
Made up of brain and spinal cord
Peripheral Nervous System (PNS)
Made up of
A. Sensory Division: Afferent: carries sensory signals to CNS
B. Motor Division: Efferent: carries signals from CNS to muscles/glands
Sensory Division
Visceral: Deep inside the body (organs, glands)
Somatic: Close to or on the surface of the body (skin, muscle, bones, joints)
Motor Division
Sympathetic/Parasympathetic
Carries signals to heart, muscles, glands
