Exercise Science Unit 2

Environmental exercise physiology

Study acute and chronic effects of exercising in various environmental conditions

Ensuring safety and optimizing performance in challenging environmental conditions is important

Endothermic

Produce our own heat internally

Homothermic

Relative stable core body temp in all environment

Core body temp:36.5-37.5C

Body fluid

~60% of body weight

Radiation

Energy transfered via infared waves

Convection

Energy transfer via mass motion of molecules

Conduction

Energy transfer via direct contact

Evaporation

Heat transfered via phase change of liquid to gas

Body temperature increases due to…

Muscle metabolism (amount of heat produced is related to intensity)

Environment (mostly radiation and heat stress)

How do we measure heat stress

Wet Bulb Globe Temperature (WBGT)

Takes into account:temperature, humidity, wind, speed, sun angle and cloud cover (solar radiation)

Heat stress differs from heat index (heat index only uses temperature and humidity and is calculated for shady areas

Farenheit→celsius

-32

1.8

Acute responses to Heat stress

-Vasodilation of blood vessels (expand to lose heat)

-increased heart rate for given activity

-increased sweating

Acute response to cold stress

shivering

vasoconstriction

non-shivering thermogenesis

shivering thermogenesis

Problems with prolonged exercise in heat

reduce muscle blood flow (especially during high-intensity exercise as blood is sent to skin)

High brain temp reduces neuromuscular drive

Dehydration

Adaptations to Heat

-Increased blood volume via plasma volume (allows for better muscle and skin blood flow)

-Widespread sweating that starts earlier in exercise

-Sweating begins at lower body temp

Problems with prolonged exercise in cold

-Hypothermia (core body temp under 35 C)

-reduced dexterity in extremities (hands)

-Skeletal muscle function decreases

-risk of frostbite

Adaptations to cold

-Better function in cold

-Lower skin temp at which shivering begins

-Increased non-shivering thermogenesis

Maintain higher hand+foot temp

Improved ability to sleep in cold

Improved dexterity 

Safety wet and cold

water increases heat loss (especially moving water)

-wet clothes decrease insulation value 

-layers=important to control temp during cold training

Clinical exercise physiology

Uses physical activity and exercise to prevent or delay the onset of chronic disease in healthy individuals

Provides therapeutic or functional benefits to individuals with disease conditions or physical disabilities

requires an understanding of how the body responds to acute and chronic physical activity and exercise in both healthy and diseased conditions

Duties&responsibilities of clinical exercise physiologist

Conducting preexercise screening

perform exercise testing and evaluation

developing exercise prescriptions

research on effects of exercise on various disease states/conditions

Exercise prescription

Plan for physical activity and exercise

Achieve specific outcomes→improved fitness, reduced disease risk, weight loss

Meets interests, goals, health needs, and clinical condition of individual

What percentage of men and women met guidelines for both aerobic and muscle-strengthening activities 

28.3% men

20.4% women

How many americans have at least one chronic disease 

Nearly half

Body Composition 

Relative amount of fat, bone, muscle mass, and water within human body

EX:BIA, DXA

Anthropometric measures

Physical measures of a person’s size, form, and functional capacities

EX:BMI (Height Weight) Circumferences (waist)

DXA

Dual X ray absorptiometry

Measures using x-ray radiation

Originally designed for bone density

Used now to determine fat, lean, bone mass

BIA

Measures electrical resistance

Used to determine fat&fat free mass

BMI

Easy to use measure that can predict risk of disease in general population

Not a measure of body composition

BMI=weight (kg)/Height (m)

Diabetes

Abnormally high blood glucose

Type 1 Diabetes

Destroyed pancreatic cells that can’t produce insulin (usually auto-immune&genetic)

Type 2 Diabetes

Insulin resistance and impaired ability to control blood glucose 

caused by diet, obesity

Atherosclerosis

Hardening of plaque inside arterial walls of damaged blood vessel

Coronary and systemic 

Neuropathy

Loss of feeling and motor control

Glomeruloscleorosis

Kidney damage

improper function of the blood vessels 

responsible for filtering blood

Diabetes Mellitus complications

Atherosclerosis

Neuropathy

Glomerulosclerosis

Diabetic retionpathy

Hypertension

Elevated pressures either systolic or diastolic

Systolic

Top number

force in vessel when heart contracts

Diastolic

Bottom number

force in vessel when heart relaxes

Cancer

Overarching term for >200 diseases, involve uncontrollable cell growth that can spread to other parts of body

Genetic mutation that results in disruption in normal cell renewal process

Benefits of exercise for cancer

Reduce sex hormones and growth factors

reduce inflammation

improve immune function

reduce dietary exposures to carciongens

Athletic Training

Involves prevention, treatment, and rehab of injuries to physically active individuals and athletes

Primary responsibilities of athletic trainers

Prevention of athletic injuries

pre-participation physical examination

being aware of physical environmental, and practice conditions that could cause injury 

Athletic trainers are __ to sport injury

First responders

Sports medicine

Umbrella term that describes various issues interrelated among medicine, physical activity, exercise, health promotion, disease prevention

Sports medicine physician

Leader of the sports medicine team

Consensus statements

Guidelines for sports medicine physicians

contains important topics relevant to providing best medical care to athletes

Guide activities and responsibilities of team physician

Isometric contraction

Muscle contract, but No change in muscle length

isotonic contraction

Same tension

Concentric

Muscle contract and shorten

Eccentric

Muscle contract and lengthen

Agonist

Prime mover-lead actress

Causes specific joint movement

Antagonist

Working against-villain

Opposing/Producing movements to the agonist

Synergist (neutralizer)

Helps prime mover do job (best supporter)

Muscle that assist agonist with movement

Stabilizer

Keeps joint stable to perform action

Stabilizer joint so agonist causes smooth and efficient movement

Lateral Raise

Agonist:Deltoid (responsible for abduction movement)

Antagonist:Latissimus dorsi (resists abduction by deltoid)

Stabilizer:trapezius (holds scapula in place)

Synergist (neutralizer):teres minor (produces external rotation that neutralizes internal rotations by lattisimus dorsi

Sternocleidomastoid

Neck

Concentric Action:Neck flexion, lateral neck flexion, rotation

Rectus Abdmominus

Abs

Concentric Action:trunk flexion

Antagonist:Erector spine

External obliques

Concentric Action:Anterior flexion, lateral flexion, rotates trunk

antagonist (Erector spine, opposite side oblique)

Erector spine

Concentric:Extends the trunk

Antagonist (rectus abdominus)

Pectoralis Major

Pecs

Concentric Action:flexes shoulder, horizontal adduction

Antagonist:Latissimus dorsi, posterior deltoid, trapezius

Latissimus dorsi

Lats

Concentric Action:extends, adducts shoulder

Antagonist:Anterior&medial deltoids, pectoralis major

Trapezius

Traps

Concentric Action:elevates, retracts, depresses scapula

Antagonist:Pectoralis Major, sternocladomastoid,anterior deltoid 

Deltoid

Shoulder

Concentric Action:Shoulder flexion, abduction, extension

Antagnoist:Pectoralis Major, Latissimus Dorsi

Infraspinatus&Teres Minor

Rotator Cuff
Shoulder external rotation

Supraspinatus

Rotator cuff

Abduction

Subscapularis

Rotator Cuff

Shoulder internal rotation

Biceps Brachii

Concentric Action:flexes elbow, forearm supination (rotating out)

antagonist:Triceps Brachii

Triceps brachii

Concentric Action:Chief extensor of elbow

Antagonist:Bicep Brachii

Brachioradialis

Forearm

Concentric Action:Flexes elbow

Antagonist:Tricep Brachii

Gluteus Maximus

Concentric action:Extends hip, Abducts hip

Antagonist:Illipsoas (hip flexor)

Illiopsoas

Hip flexor

Concentric:Flexes hip&trunk

Antagonist:gluteus maximus

Quadriceps femoris

Quads

Concentric Action:extends knee

Antagonist:Hamstring

Hamstring

Concentric Action:flexes knee, extends hip

Antagonist:quadriceps femoris

Gastrocnemius

Calves

Concentric Action:Plantar (point) flexes ankle, assists in knee flexion

Antagonist:Tibialis anterior

Tibialis Anterior

Shin

Concentric Action:Major dorsiflexor (raise up) the ankle

Antagonist:Gastrocnemius

Mechanical injuries

Caused by forces placed on an object that changes the shape of object

Injuries will occur with different magnitudes and frequencies

Compression

Pressing/Pulling force directed through body

Tension

Pulling/stretching force directed through body

Shear

Force directed parallel to surface

Fractures

Causes

Direct force:Force applied at location of fracture

Indirect force:Force applied in different area of body and translated to fracture site

Friction Blisters

Caused by shear forces between layers of skin

common on feet and hands

Sprains

Tearing/Damage to ligament

Ligament

Connective tissue connecting bone to bone

ACL Tear (sprain)

Anterior cruciate ligament

major ligament inside knee joint

typically caused by shear forces

Resists:Hyperextension of knee

Why ACL injuries higher in females

Difference in structure

Ligament laxity (hormones)

Muscle strength

Ulnar Collateral Ligament Tear

Medial side of elbow (connects humerus to ulna)

Resists:Outward stress placed on elbow when arm=extended

Typically caused by shear forces

Strains

Tearing/damage to muscles or tendons

Most often occurs during eccentric contractions extending/being stretched

Tendons

Connective tissue connecting muscles to bones

Hyaline Cartilage

Gel-like interior

Most common type in body

most joint surfaces, trachea, ribs, nose

Fibrocartilage

Greater Collagen content

Meniscal tear

Each knee has 2 menisci

causes:loaded twisting

Labral Tear (cartilage injury)

Labrum

Ring of fibrocartilage around shoulder and hip socket to aid with stability of joint

Dislocation

When bones of joint are out of alignment

Synovial joint

Joint cavity filled with synovial fluid surrounded by fibrous articular capsule, lined with synovial mebrane

Herniation

Portrusion of nucleus pulposus through annulus fibrosis (when all or part of soft, jelly-like center of spinal disk pushes through a weakend part of disk’s outer ring

caused by compression forces, shear forces

Concussion

TBI that affects brain function

occurs when brain is shaken/jolted by impact

Arthroscopic surgery

Minimally invasive procedure used to examine&treat damage to interior of joint

ACL reconstruction

Surgical procedure using graft replacement from another part of body

UCL reconstruction

Ligament in medial elbow is replaced with tendon from elsewhere in body

Autologous chrondrocyte implantation

used to repair defects in articular cartilage of joints by injecting cultured cells into joint