KNR 205: Scientific Principles of Coaching

Introduction

Slide 2

General course stuff

The course is designed for athletic coaching minors, but available to KNR majors

Have you had any of these... 181 (A&P), 240 (Fitness), 280 (Ex. Phys.), 282

(biomechanics)? If so, you’ll be duplicating information you’ve

already covered. This course was designed to cover aspects of all

those courses, as well as 254 and 257, so that it would function as a general intro to kinesiology for minors

Slide 3

General course stuff

Consequences for course organization A lot of material Broad and shallow approach Focusing on “getting the idea” of a number of

areas Assessments that survey basic familiarity rather

than mastery

Slide 4

General course stuff

To do this week...1. Download these slides (chapters 1 and 2) and

print them up. You should be able to print multiple slides per page – I recommend 3 slides a page

2. Read chapters 1 & 2 and answer the online quiz on chapter 2 (deadline to be announced – it’ll be some time next week)

Slide 5

Chapter 1: Introduction

We’re going to skim this and get into the nitty gritty of chapter 2 ASAP

As this course is designed as the survey course for the coaching minor, it makes sense to read about the discipline a little first.

The best summary I can see in the text is on page 4, figure 1.1 As you can see, it’s busy. There’s a lot of stuff, and

a lot of influences

Or, as we call it, kinesiology

Part One: Anatomical Bases of Human Movement

Functional Anatomy

Slide 8

General intro...

Again, we’ll skim this introduction so we can get to the meat of chapter 2.

Human anatomy is essentially about the structure and function of the human body

Functional anatomy is about human anatomy doing its daily business – moving and being physically active (3 areas – bones, joints, muscles) “dynamic anatomy”

Can be from a number of levels of analysis Subcellular Tissues Organs

Chapter 2

Basic Concepts of the Musculoskeletal System

Slide 10

Objective (from syllabus)

To understand key concepts related to the structure and function of the skeletal, articular (joint) and muscular systems You’ll find I stick very closely to the book

throughout (like a drowning man clutching driftwood)

I see my role as a facilitator, whose job it is to simply relate and explain the content of the text to you

As such, I need you to simply point out where I’m not being clear

Slide 11

Tools for Measurement

Bone density: radiology

Bone structure chemical preparation

Bone composition chemical analysis

Movement: goniometry (joint motion) dynamometers (muscle force)

Slide 12

The skeletal system

Functions Mechanical

Weight bearing Protection (e.g. brain, lungs) Contribution to movement (linkages, muscle

attachment sites) Physiological

Bone can heal itself & perform maintenance “Living” vs. “dead” bone

Mineral storage (calcium, phosphorus) Marrow – produces blood cells

Slide 13

The skeletal system

Bone composition Mechanical properties & bone composition

Stiffness, flexibility, tensile strength, etc... Multiple components – the whole is greater than the sum

of the parts ¼ water...also contains minerals like calcium, phosphorous Healthy bone: 1/3 organic (collagen), 2/3 mineral (salts)

We don’t have to learn the exact properties! Osteocytes – basic cells Osteoblasts – bone-forming cells Osteoclasts – bone-eroding cells

Bone remodeling – 3 months

Slide 14

The skeletal system

Bone composition Types of bone

Spongy More porous, springy – easy to supply with blood (and

keep alive) Compact

More solid, different in structure – we won’t go into details, but it implies that compact bone is organized specifically to address the difficulty of supplying blood to the entire bone

Slide 15

The skeletal system

Architecture of bone Light and weight bearing – implies efficiency

Shape and organization Generally, the structure mirrors the function. E.g.:

Long bones – rigid links for movement Flat bones of skull – “bicycle helmet” design Hindfoot – compact and spongy bits to absorb ground

reaction forces Vertebra – mixture of each of these types

The skeletal system

Architecture of bone Architecture of long

bones Hollow shafts confer

mechanical advantages

Large end points absorb compression forces

Slide 17

The articular system

Classification of joints The different classifications are based on the

different materials forming each type. Types are: Fibrous (e.g. teeth to jaw, between bones of skull,

between bones in long bones in arms & legs) Cartilaginous (e.g. between growth plates in bone, or

between vertebrae) Synovial – all over the place, and affords most

movement, so the focus here

Neither allows much

movement

Neither allows much

movement

The articular system Features of synovial joints

Cartilage – sponge (smooth surface and force absorber)

Joint capsule – more firm (joint stability, forms boundary)

Synovial membrane – inner layer of capsule, forms synovial fluid, removes cell debris

Synovial fluid: Lubricates Protects Provides nutrition (for

cartilage) Ligaments – attach across

bones to protect against large movement of the joint

Collagen fibersCollagen fibers

Blood bits, synovial

membrane secretions,

debris

Blood bits, synovial

membrane secretions,

debris

Changes viscosity &

volume with activity

Changes viscosity &

volume with activity

Activity also

“flushes” the joint

Activity also

“flushes” the joint

90% Collagen

fibers

90% Collagen

fibers

The articular system Classification of synovial joints

See figure 2.7 (types) Hip, ankle, finger knuckle,

elbow, spinal vertebrae Range of movements allowed by

synovial joints See 2.8 (movement types) Also spin, slide and roll

Joint protection, lubrication, and wear See 2.5 again – add

cartilage for sponge, and synovial fluid for slipperiness

Spheroid, hinge,

uniaxial, biaxial, simple,

compound, complex

Spheroid, hinge,

uniaxial, biaxial, simple,

compound, complex

Slide 20

The articular system

The joint as the functional unit of the musculoskeletal system The idea here is that there are a lot of factors affecting the

structural integrity (stability) of a joint The bones provide the major part of the joint, but also aid in

cushioning forces Muscles stabilize the joint by producing force across it Tendons transmit muscle forces to the joints Motor and sensory nerves allow the joint to function in the

context of the entire body’s movement The point here is that injury to one part of a joint can be

seen to affect many other parts of the system (“chain reaction”)

Slide 21

The muscular system Structure

Bone-tendon-muscle-tendon-bone Association of muscles with other structures

Connection points determine direction of action of contractile force

Structural features of muscle Types – skeletal, smooth, cardiac Shape – normally elliptical, can vary (can’t see how this

matters too much) Components – see slide 24 – basic functional component is

the motor unit, which may comprise few or many muscle fibers (and that is indirectly associated with the degree of fine control you have over the contraction) (less fibers p/unit…more fine control)

Slide 22

The muscular system

Structure Distinguishing properties

Excitable Contracts Conducts Can extend Is elastic

The muscle and its parts

The muscle as a whole

Slide 23

The muscular system

Structure Muscle contractions

Sliding filament hypothesis Cross-bridge hypothesis Activation via electrical and mechanical responses:

excitation-contraction coupling Chemical release from nerve-muscle junction (causes

voltage) Signal conducts along muscle Electricity indirectly causes attachment between actin

and myosin filaments Myosin filaments pull actin filaments towards center Leads to cross-bridge cycling...

Muscles contract via overlap of protein filaments (going

from not much overlapping to much overlapping)

Muscles contract via overlap of protein filaments (going

from not much overlapping to much overlapping)

Myosin attaches to actin and pulls on z-line

(shortening sarcomere)

Myosin attaches to actin and pulls on z-line

(shortening sarcomere)

Release of calcium

ions...exposure of active sites on

actin – myosin attaches

Release of calcium

ions...exposure of active sites on

actin – myosin attaches

The muscular systemPow

er stro

ke

Cross-bridge cycling...

The muscular system

Mechanics of muscular action Types of contraction

Concentric produces movement

Isometric stabilizes joint

Eccentric controls movement

Slide 26

The muscular system

Mechanics of muscular action Explaining joint actions

Mono-, bi-, and poly-articular muscles Not easy – muscles interact in very complex ways –

gives rise to a whole sub-discipline Muscles’ ability to move the joint depends on ability

to shorten and lengthen – has limits (see diagram on p. 31, and the wrist example)

Determinants of strength See ch. 6!