Kinesiology Laboratory 3: Mechanical Considerations during Qualitative Analysis of Movement

Today’s Activities Presentations Lever Class Review Activity Analysis Push up Bench press PNF Techniques

Presentations Take good notes, especially for those you are unsure of These activities will be on the Midterm Practical!

How our bodies produce movement Movement occurs around joints Flex, abduct, upwardly rotate, etc. Movement also occurs on a single plane, about a single axis Ex. Frontal These movements are caused by muscle contractions Concentric/Eccentric/Isometric These movements can occur against a resistance Gravity, body weight, resistive equipment

A R E Lever Classes *Load=Resistance *Fulcrum= Pivot Point= Axis xis ffort

1st Class Lever Seesaw Where the axis is determines the mechanical advantage Axis close to effort results in greater speed and ROM Axis close to resistance results in greater force production Elbow Extension Effort= Olecranon Process (Insertion of Triceps) Axis= Elbow Joint Resistance= Forearm [+/- additional weight]

2nd Class Lever Wheelbarrow Produces largest force production but has less ROM Very few examples exist in the body Plantar Flexion Effort= Calcaneous through Achilles tendon (insertion of calf muscles) Resistance= Whole body (+/- added weight) Axis= Ankle Joint

3rd Class Lever Tongs Elbow Flexion Axis= Elbow Joint Effort= Insertion of Biceps Brachii Resistance= Forearm (+/- added weight) This lever has the advantage of higher speed and greater ROM Most common lever in the human body

Activity Analysis: Push Up/Bench Press Chart breaking down the movement by joint FOR BOTH PHASES Osteokinematic motion (Flex, adduct, etc.) Muscle Functional Group (i.e. Wrist Flexors) Agonist & Synergists Contraction Type Planes and axes Effects of gravity (Resisting, Assisting, No effect) Diagram of movement (up phase/down phase) Use arrows for gravities effect Diagram of a single joint Identify muscle group and Contraction Type Identify the type of lever Label the Axis, Effort and Resistance

Proprioceptive Neuromuscular Facilitation (PNF) Stretching Techniques to Increase ROM at a tight muscle Commonly used on Hamstrings Why is hamstring flexibility a problem in modern society? Two principles Golgi-Tendon Organ (GTO) Firing Reciprocal Inhibition

Golgi Tendon Organs The GTO are receptors of the tendons of skeletal muscle They detect changes in tension along the muscle fibers They relay this information to the spinal cord and brain When muscle tension is too great, the GTO send inhibitory impulses, causing the muscle to relax (stop contracting)

Reciprocal Inhibition Impulses that cause an antagonist muscle to relax (decrease tension) in order for agonist muscle to contract Occurs on opposite “sides” of joint in sequence “Pulled Hamstring” occurs when reciprocal inhibition backfires and quads and hams are contracted at the same time

Proprioceptive Neuromuscular Facilitation (PNF) Stretching Hold- Relax Contract-Relax Agonist Contraction Hold-Relax with Agonist Contraction These techniques are often combined clinically

Hold-Relax Flex subjects hip to end of ROM Take measurement with Goniometer Have subject isometrically contract hamstrings (antagonist to hip flexion) for 6 seconds Use verbal cues, “Push against my hands”, etc. Tell subject to relax hamstring Flex subjects hip further and hold for 10-30 seconds Take second Goniometer measurement

Contract-Relax Flex subjects hip to end of ROM Take measurement with Goniometer Have subject isometrically contract hamstrings (antagonist to hip flexion) for 6 seconds Use verbal cues, “Push against my hands”, etc. Tell subject to relax hamstring Have subject concentrically contract quadriceps to flex hip and hold for 10-30 seconds Take second Goniometer measurement

Agonist Contraction Have subject concentrically contract quadriceps to flex hip to end of ROM Take measurement with Goniometer Have subject isometrically contract hamstrings (antagonist to hip flexion) for 6 seconds Use verbal cues, “Push against my hands”, etc. Tell subject to relax hamstring Have subject concentrically contract quadriceps to flex hip and hold for 10-30 seconds Take second Goniometer measurement

Hold-Relax with Agonist Contraction Have subject concentrically contract quadriceps to flex hip to end of ROM Take measurement with Goniometer Have subject isometrically contract hamstrings (antagonist to hip flexion) for 6 seconds Use verbal cues, “Push against my hands”, etc. Tell subject to relax hamstring Flex subjects hip further and hold for 10-30 seconds Take second Goniometer measurement

For Next Week Lab Report 3 Readings: H&K: Ch5 cont’d. ,TG: 149-166