Finals: AEROBIC EXERCISE Flashcards
Defined as any bodily movement produced by skeletal muscle contraction resulting in increased energy expenditure over resting levels.
Utilizes energy and requires regular participation for fitness.
Physical Activity
Measure of the body’s capacity to use oxygen, typically expressed in mL/kg per minute.
Determined by factors including oxygen transport, cardiac function, and muscular oxidative potential.
Maximum Oxygen Consumption (VO2 max)
Planned and structured physical activity aimed at improving or maintaining physical fitness.
Goal-directed and involves intentional efforts to enhance fitness levels.
Exercise
The ability to perform physical work, encompassing cardiorespiratory functioning, muscular strength and endurance, and musculoskeletal flexibility.
Achieved through regular participation in activities challenging the cardiorespiratory system.
Physical Fitness
Cardiorespiratory endurance training aimed at augmenting muscle energy utilization through a structured program.
Improvements in endurance are achieved through increased oxidative enzymes, mitochondrial density, and muscle fiber capillary supply.
Aerobic Exercise Training
Ability to work for prolonged periods and resist fatigue, including muscle and cardiovascular endurance.
Guidelines involve using large muscle groups and challenging the cardiovascular system.
Endurance
Overload vs Specificity Principle
Overload principle: Cardiovascular system adapts over time with consistent challenge.
Specificity principle: Tailoring exercise to the individual’s fitness level to elicit significant improvements.
Rapid decreases in maximum oxygen consumption, cardiac output, and muscular strength due to extended acute illnesses or chronic conditions.
Mitigated through active engagement in upper extremity activities and avoidance of prolonged bed rest.
Deconditioning
Highlighting fuel sources, aerobic vs anaerobic processes, types of activities supplied, and their roles in exercise.
Energy Systems Overview
Phosphagen (ATP-PC) System
Fuel Source: Phosphocreatine.
Anaerobic; supplies short, quick bursts of activity.
Activity duration: first 30 seconds.
Anaerobic Glycolytic System
Fuel Source: Glycogen through glycolysis.
Anaerobic; supplies moderate intensity, short-duration activities.
Duration: 30th to 90th second.
Measure of oxygen consumed by the myocardial muscle.
Determinants include heart rate, systemic blood pressure, myocardial contractility, and afterload.
Myocardial Oxygen Consumption
Aerobic System
Fuel Source: Utilizes oxygen; glycogen, fats, and proteins.
Aerobic; supplies longer duration activities.
Predominant after 2nd minute of exercise.
Goal of Energy Systems
Produce ATP, the cell’s energy currency.
Phosphagen: short bursts of activity.
Anaerobic Glycolytic: moderate intensity, short duration.
Aerobic: longer duration activities.
Process of activating motor neurons and associated muscle fibers.
Essential for muscle contraction and force production.
Recruitment of Motor Units
Functional Implications of Muscle Fiber Types
Burst of Intense Activity: ATP-PC system.
Intense Activity lasting 1-2 minutes: Anaerobic and ATP-PC.
Large Muscle Activity: All energy systems.
Submaximal Activity lasting 20-30 minutes or more: Aerobic system.
Often expressed in kilocalories, categorized as light, moderate, or heavy.
Factors affecting energy expenditure include mechanical efficiency and body mass.
Energy Expenditure
Classification of Activities
Light Work: 2.0-4.9 kcal/min, 1.6 to 3.9 METs.
Heavy Work: 7.5-to 9.9 kcal/min, 6.0 to 7.9 METs.
Work Output (W = F x D) vs. Work Input (W= VO2max (used) - VO2max (rest)).
Expressed as a percentage.
Efficiency
Quantification of Energy Expenditure
Kilocalorie: Measure expressing energy value of food.
MET: Oxygen consumed per kilogram of body weight.
Conversion of METs to Kilocalories.
Characteristics: Slow to contract, rich in myoglobin and mitochondria.
Functional Implications: Suited for endurance activities, such as long-distance running or cycling, due to high oxidative capacity.
Slow-twitch fibers (Type I):
Characteristics: Fast contractile responses.
Functional Implications: Adapted for power activities like sprinting or weightlifting due to high glycolytic capacity.
Fast-twitch fibers:
Characteristics: Fast contractile response, low myoglobin content.
Functional Implications: Utilized for quick bursts of energy, such as jumping or throwing, due to high glycolytic capacity.
Type IIB - Fast:
Characteristics: Intermediate characteristics between Type I and Type IIB fibers.
Functional Implications: Recruited for both anaerobic and aerobic activities, contributing to activities of moderate intensity and duration.
Type IIA - Fast:
Ideal for activities requiring endurance, as they can sustain contractions over prolonged periods without fatigue.
Slow-twitch fibers (Type I):
Examples of Activities for Each Muscle Fiber Type: Slow-twitch fibers (Type I):
Long-distance running, cycling.
Fast-twitch fibers:
Type IIB - Fast: Suited for short, explosive movements due to rapid contractile responses.
Type IIA - Fast: Versatile fibers recruited for a range of activities, including both anaerobic bursts and sustained aerobic efforts.
Examples of Activities for Each Muscle Fiber Type :Type IIB - Fast:
Sprinting, jumping.
Examples of Activities for Each Muscle Fiber Type: Type IIA - Fast:
Activities requiring both endurance and bursts of power, such as soccer or basketball.
Determinants of Aerobic Exercise
Frequency and intensity
Frequency: Varied based on health and age; 3-4 sessions/week for cardiovascular changes.
Intensity: 60-90% HRmax or 50-85% VO2 max; determined using HR reserve or percentage of HRmax.
Determinants of Aerobic Exercise
Time and Type
Time: Optimal duration is 20-30 minutes/session at 70% MHR; varies based on intensity.
Type: Large muscle groups rhythmic and sustained; follows the reversibility principle.
General Recommendations for Aerobic Activity
for each age groups
Children (6–17): 60 minutes/day of moderate to vigorous activity.
Adults (18–65): 30 minutes/day of moderate or 20 minutes/day of vigorous activity, 5 days/week.
Older Adults (65+): Same as adults; activity can be accumulated in bouts of 10 minutes.
Children: Varied HR, stroke volume, BP; endurance increases with age.
Younger Adults: Stable HR, increased stroke volume, BP; peak muscle mass between 18-25 years.
Older Adults: Decreased HR, stroke volume, cardiac output; decreased arteriovenous oxygen difference.
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