Cardiovascular Fitness • The ability of the body to utilize oxygen efficiently.
Cardiovascular Fitness • In designing the exercise prescription, keep in mind that some people engage in aerobic exercise to improve their health status or reduce their disease risk, while others are primarily interested in enhancing their physical fitness and performance levels.
Cardiovascular Fitness • Given that the quantity of exercise needed to promote health is less than that needed to develop and maintain higher levels of physical fitness, you must adjust your exercise prescription according to your client’s primary goal.
Cardiovascular Fitness • Improvement is CV fitness is measured by assessing changes in VO2MAX
Cardiovascular Fitness • Increases in VO2MAX may range from 5 to 30%.
Cardiovascular Fitness • Individuals with low initial levels of fitness, cardiac patients, and those exhibiting large losses of body weight will demonstrate the greatest percent increase in VO2MAX.
Cardiovascular Fitness • Similarly, more modest increases may be expected from healthy individuals with high initial levels of fitness and those who exhibit little change in body weight.
Improved Health • When the primary goal for the exercise prescription is improved health, the following guidelines are recommended:
Improved Health • Mode: • Select endurance-type physical activities, including formal aerobic exercise training, house and yard work, and physically active, recreational pursuits.
Improved Health • Intensity • Prescribe at least moderate intensity physical activities (> 40 - 45% of VO2R or HRR, and 55-64% of HRMAX).
Improved Health • Frequency • Schedule physical activity for most, preferably all days of the week.
Improved Health • Duration • Accumulate at least 30 minutes of activity each day. • Duration varies depending on type of activity.
Optimal Fitness • When the primary goal for the exercise prescription is to attain optimal fitness, the following guidelines should be followed.
Mode • The greatest improvement in VO2MAX occurs when exercise involves the use of large muscle groups over prolonged periods and is rhythmic and aerobic in nature.
Mode • A wide range of activities provides for individual variability relative to skill and enjoyment, factors which influence compliance to the exercise program and thus desired outcomes.
Mode • It may be desirable to engage in several different activities to reduce repetitive orthopedic stresses and involve a greater number of muscle groups.
Mode • Because improvement in muscular endurance is largely specific to the muscles involved in exercise, it is important to consider unique vocational or recreational objectives of the exercise program when selecting activities.
Mode • Finally, it is important to consider other barriers that might decrease the likelihood of compliance with, or adherence to, the exercise program (travel, cost, spousal or parent involvement, etc.).
Intensity • Intensity and duration of exercise determine the total caloric expenditure during a training session, and are integrally related.
Intensity • That is, similar increases in CV endurance may be achieved by a low intensity, long duration session as well as a higher intensity, shorter duration session.
Intensity • The risk of orthopedic injury may be increased with the latter; however, programs emphasizing low-to moderate-intensity exercise with a longer training duration are recommended for most individuals.
Intensity • Part of the art of exercise prescription is being able to select an exercise intensity that is adequate to stress the cardiovascular system without overtaxing it.
Intensity • As a general rule, the more fit the individual, the higher the exercise intensity needs to be to produce further improvement in CV fitness.
Intensity • ACSM recommends that the intensity of exercise be prescribed as 65 to 90% of maximum heart rate, or 50 to 85% of VO2R or heart rate reserve.
Intensity • VO2R refers to maximum oxygen uptake reserve. • It is calculated by subtracting resting VO2 from VO2MAX
Intensity • However, individuals with a very low initial level of fitness respond to a low exercise intensity, for example 40 to 49% of VO2R
Intensity • Several important factors to consider prior to determining the level of exercise intensity include:
Intensity • Individual’s level of fitness. • Presence of medications that may influence heart rate
Intensity • Risk of cardiovascular or orthopedic injury. • Individual preferences for exercise. • Individual program objectives.
Intensity Factors that can impact intensity include: • Altitude • Humidity • Temperature • Terrain
Intensity • Exercise surface • Equipment
Intensity • Several methods may be used to determine exercise intensity.
HR Methods • Using HR as a guide to exercise intensity is useful, given the relatively linear relationship between HR and VO2
HR Methods • When prescribing exercise intensity based on HR, consideration must be given to potential influences.
HR Methods • Given exercise test data, there are several approaches to determining an exercise HR range for prescriptive purposes:
HR Methods • Using a straight percentage of HRmax • Using the HR reserve method. • Plotting HR vs VO2 or exercise intensity during the exercise test.
HR Methods • Go over each method: • HRmax • Karvonen • Plotting
HR Methods • It is important to note that the HR response to graded exercise is somewhat dependent on the mode of exercise testing.
HR Methods • For example, compared to treadmill testing, exercising on an electronic step ergometer elicits higher HRs, and stationary cycling typically results in somewhat lower HRs at the same relative exercise intensities.
HR Methods • When using the plotting method to obtain HRs for an exercise prescription, be sure to match the exercise testing and training modes by selecting a testing mode that elicits HR responses that are similar to those obtained for the training mode.
HR Methods • Using HR exclusively to develop intensity recommendations for your clients’ exercise prescriptions may lead to large errors in estimating relative exercise intensities for some individuals.
HR Methods • Medication, emotional states, and environmental factors such as temperature, humidity, and air pollution can affect your clients’ exercise training heart rates.
METS • Prescribing by METs is most logically applicable to the apparently healthy and those with high VO2MAX values
METS • It is less applicable for individuals with cardiac or pulmonary disease, or for individuals with low functional capacities.
METS • First, assess the client’s functional aerobic capacity using a graded exercise test.
METS • Use this value to determine the minimum, average, and maximum conditioning intensities.
METS • For example, if the VO2MAX is 35 ml . kg-1 . min-1 , the functional capacity is 10 METs. • 1 MET = 3.5 ml . kg-1 . min-1
METS • The minimum training intensity is 50% of this value or 5 METs; the average intensity is 60 to 70% or 6 to 7 METs; the maximum exercise intensity is 85% or 8.5 METs.
METS • Thus, the exercise prescription for an apparently healthy, active individual should include activities that produce an average intensity of 6 to 7 METs.
METS • The exercise intensities (METs) for walking, jogging, running, cycling, and bench stepping are directly related to the speed of movement, resistance, or mass lifted.