Unit 2 Flashcards
Voluntary or involuntary movement : skeletal muscle
Voluntary. Eg biceps, quads
Voluntary or involuntary movement : smooth muscle
Involuntary. Eg gastro- intestinal peristalsis movement
Voluntary or involuntary movement : cardiac muscle
Involuntary. Eg. Heart muscle contraction
Define eccentric
Muscle lengthening under tension
Define isometric
No change in muscle length under tension
Define concentric
Muscle shortening under tension all load
Factors that influence tension generation in skeletal muscle: cross section and size of muscle
The larger the muscle diameter, the greater the force it can produce
Factors that influence tension generation in skeletal muscle: muscle architecture fibre arrangement and length
Short fibres= higher force
Long fibres= less force
Factors that influence tension generation in skeletal muscle: fibre type
Type 1: slow, low force
Type 2: rapid high force
Factors that influence tension generation in skeletal muscle: type of muscle contraction
Eccentric > isometric > concentric
Factors that influence tension generation in skeletal muscle: speed of muscle contraction
Concentric: increase speed= decrease force
Eccentric: increase speed = increase force
Define local muscle fatigue
diminished response of a muscle to repeated stimulus. An acute physiological response that is normal and reversible
Define general cardio respiratory fatigue
Diminished response of the entire body from prolonged physical activity. Related to the body’s ability to use oxygen
Signs and symptoms of muscle fatigue
Uncomfortable sensation within the muscle such as pain or cramping, tremor in muscle during contraction, active movements are jerky, inability to complete the movement pattern through full ROM during exercise, use of substitute movements, inability to continue low- intensity physical activity
Physiological adaptations to resistance exercise: skeletal muscle adaptations
Hypertrophy - increase in size of an individual muscle fibre, usually occurs by 4-8 weeks of strength training, accounts for strength gains in muscle, associated with high volume moderate resistance eccentric training.
Muscle finer type adaptation - transformation of type 2 muscle fibres to make them more fatigue resistant
Physiological adaptations to resistance exercise: neural adaptations
The initial rapid gain in the tension- generating capacity of skeletal muscle is largely attributed to neural responses, not adaptive changes in muscle
What is overtraining
A decline in physical performance in healthy individuals participating in a high intensity, high volume strength and endurance training program. Often caused by poor training, insufficient diet including hydration and inadequate rest. Individual progressively fatigues more quickly and requires more time to recover. Preventable and reversible.
What is overwork
Progressive deterioration of strength in muscles already weakened by non-progressive neuromuscular disease
Acute muscle soreness
Develops during or directly after strenuous exercise performed to the point of muscle exhaustion. Pain subsides quickly after exercise. Due to lack of adequate blood flow and oxygen and a temporary buildup of metabolites, such as lactic acid.
Delayed onset muscle soreness (DOMS)
Develops approx. 12-24 hours after muscular overexertion. Most severe after repetitive high intensity eccentric exercise. Intensifies and usually peaks by 24-48 hours after exercise
Define Vo2 max
A measure of the body’s capacity to use oxygen. The maximum amount of oxygen consumed per min when the person has reached maximal effort. Usually expressed relative to body weight
Define cardiac output
Volume of blood pumped by the heart per min.
Calculate cardiac output
Stroke volume X heart rate
Define stroke volume
Volume of blood pumped by one ventricle in 1 heart beat
3 types of muscle in the human body
Skeletal muscle, smooth muscle, cardiac muscle
Acute cardiovascular response to exercise
Sympathetic
Nervous system - vasoconstrict blood vessels to non-exercise muscles- vasodilate blood vessels to exercising muscles. - increase cardiac output by increasing heart rate and increasing stroke volume - increase systolic blood pressure. Result is deliver more oxygen to the working area/muscles
Long-term cardiovascular response to exercise
At rest: decreased resting heart rate, decrease blood pressure increase blood volume and hemoglobin
During exercise: decreased exercise heart rate, increased stroke volume and increase cardiac output, increase extraction of oxygen by a the working muscles
Result: more efficient cardiovascular function during exercise
Acute respiratory response to exercise
Occurs before exercise starts, increased respiratory rate, increase O2 and CO2 exchange in the lungs, increase muscle metabolism
Long-term respiratory response to cardiovascular exercise
At rest: larger lung volumes, greater alveolar-capillary surface area
During exercise: greater oxygen/CO2 exchange, lower respiratory rate with the same oxygen consumption, increased maximal RR
Health benefits to cardiovascular exercise
Reduced risk of high blood pressure, stroke and coronary heart disease, reduce percentage of body fat, decreased risk of obesity, reduced risk of some forms of cancer, reduce stress, increased sense of well-being, improve sleep
Aerobic exercise
Uses oxygen. Continuous long duration such as swimming or a long distance running, 15 to 60 minutes.
Anaerobic exercise
Does not require oxygen. Short duration high intensity interval’s typically 90 seconds or less 1:3 work/ rest ratio.
Heart rate is affected by
Genetics, age, temperature, emotions, medications, general health
How to measure your heart rate
Do not use them as a has a pulse of its own, press gently using one or two fingers when measuring Paul’s, measure using carotid or radial sites, measure for 10secsX6, or for 15secsX4, 30secsX2
Calculating target heart rate training zones : method 1
Lower limit = 170-age
Upper limit = 200 -age
Calculating target heart rate: method 2
Lower limit = (220-age) x 60%
Upper limit = (220-age) x 90%
Calculating target heart rate: method 3
% intensity + resting HR
How will hyperthermia affects the body’s response to physical activity
The body produces more heat than it can dissipate and may not be able to adequately cool secondary to dehydration excessive heat or humidity
Levels of hyperthermia
Heat cramps heat exhaustion and heat stroke
Hypothermia effects on the body’s response to physical activity
When exercising in cold weather, the body continues to lose heat through sweating, decreased core body temperature accord temperature of less than 27°C can result in unconsciousness and death
Hi altitudes effects of the body’s response to physical activity
Less oxygen available, labored breathing, increased heart rate, headaches, longer recovery times
