Cardiorespiratory Endurance Chapter 2

Kinesiology 2115

Cardiorespiratory Endurance

(also called cardiovascular endurance)

• • • Describes our energy output Most important component of physical fitness for longevity Cardiorespiratory endurance is the ability to supply oxygen to working muscles over a period of time

Function of the CR System

• • • • Four components of the CR System – Heart, blood vessels, blood and lungs Purpose – Take in and deliver oxygenated blood to the cells of the body – Remove deoxygenated blood and other waste products from the body Which side of the heart pumps deoxygenated blood to the lungs?

– ________ atrium and ventricle Which side pumps oxygenated blood to the body?

– _______ atrium and ventricle

Regulation of the CR System

• • • Cardiac Output: the volume of blood pumped per minute – Average adult volume?

– Stroke Volume: amount of blood pumped per beat – CO = dec HR X inc SV – When the body exercises, how much blood is pumped per minute?

With improved fitness, cardiac output will increase stroke volume and consequently decrease heart rate There is a maximum heart rate!

– HR max = 220 - age

Regulation (Continued)

• • Maximum cardiac output is effected by maximum Heart rate – HR max decreases with age – What happens to CO max with age? Blood Pressure is also a factor – Blood pressure: the force of blood against vessel walls – Arterial (contraction) pressure is the systolic pressure – Pressure when the heart relaxes (between beats) is the diastolic pressure – Normal BP? – Borderline hypertensive?

Energy Systems

• • Metabolism – ATP (Adenosine Triphosphate) – ATP-PC system 1- 10 seconds – Anaerobic system – Aerobic system 10 seconds-3 minutes >3 minutes – Most activities combine anaerobic and aerobic systems Maximal Oxygen Consumption (VO 2 max) – Ability to utilize oxygen while working and removing CO 2

Energy Systems (Continued)

• VO2 max is one of the best measures of cardiorespiratory endurance – The higher your VO2 max, the more you can delay fatigue-oxygen debt – (This means you’re more fit) – You can recover from oxygen debt more quickly – Can be measured in the lab or a field test (examples of lab test: treadmill or stationary bike)

Testing VO

2

Max

• • • • • • • • •

Physiological Benefits of CR Endurance

Greater CO: more blood, faster Longevity Improved VO2 max: produce more ATP Lowered blood pressure Reduced body fat, firm muscles Increased metabolism, remains elevated after exercise Increase HDL cholesterol, lower LDL Less bone mineral loss Curbing of appetite

•

Acute/Chronic Changes with Aerobic (Cardio) Exercise

Acute – Increased metabolism – Increase CO – Systolic blood pressure – Ventilation (respiratory rate) – Muscle hypertrophy resulting in the slowing of digestion • Chronic – Increased metabolism due to increase in lean muscle mass – Lower resting HR – Increased SV – Increased cellular activity – Increased capillarization of muscle – Improved oxygen utilization, muscle glycogen  All return to normal quickly after exercise ends  Must maintain over a lifespan or changes will revert back

• • • • • •

Aerobic Exercise Plan Considerations

Precautions Objectives Assess current fitness level Mode Selection Safety Concerns Staying Motivated

• • •

Mode of Exercise

Warm-up – 5-10 minutes LIGHT cardio followed by LIGHT stretching Activity Period – Overload principle – Intensity (how hard) • Rate of Perceived Exertion (RPE) or • Target Heart Rate range – [(220-age) – RHR] x % intensity range + RHR – % intensity range dependant upon current health status – Duration (how long) – Frequency (how often) Cool-down – LIGHT cardio and stretching

Types of Aerobic Exercise

High Aerobic Potential

Aerobic dance Aerobic walking Bicycling Cross-Country skiing Hiking uphill Jogging Rope jumping Rowing Running Stair climbing Swimming

Moderate Aerobic Potential

Basketball Calisthenics Downhill skiing Field hockey Handball Racquetball Soccer Squash Tennis (singles)

Low Aerobic Potential

Archery Baseball Bowling Football Golf Softball Volleyball

Implementing a Program

• • • • • Evaluate initial fitness level Schedule exercise as a part of your day Find a variety of modes Keep in target heart rate zone – Increase duration and frequency before intensity Be aware of overtraining – Start between 500-2000 calories per week • • You don’t want to lose more than 2 lbs per week 3500 calories = 1 lb

Benefit to Risk Ratio

• • • Health Risks (Consult a physician) Sudden illness, hidden heart problems Stop exercising and contact MD if: – Pain in the chest, under sternum, or radiating to the arm; also, any other unexplained pain – Irregular pulse rate (flutters or rapid rate changes) – Palpitations in the chest or throat – Dizziness, lightheadedness, confusion or fainting

Note: Anything out of the ordinary, even if you are in shape

Other Health Considerations

• • • Muscle soreness and injuries – Delayed onset muscle soreness is normal - 24-48 hours later – If it persists, the muscles have been worked too hard Basic musculoskeletal injuries – Rest – Ice – Compression – Elevation Most exercise injuries are caused by poor warm-up, mechanics, equipment, increasing intensity or duration too quickly

Preventing Injuries

• • • • • Warm-up thoroughly Gradual progression Listen to your body – RICE and ibuprofen Avoid poor biomechanical situations – Running in one direction – Running on slanted roads, downhill – Poor shoes – Avoid hard surfaces Substitute with lower impact exercises – Machines (elliptical, stationary bike), swimming, walking

Heat Illnesses

• • • • • Check temperature and humidity – Adjust duration and intensity – Exercise during cool times, in the shade and wear loose clothing Drink before, during and after exercise Replenish electrolytes (salt, potassium) Sedentary, overweight, older at greater risk Acclimatize