Chapter 11: Cardiorespiratory Training-Programming and Progressions Flashcards
Fundamental Physiological Adaptations of the Muscular System
- during low intensity endurance exercise, there are adaptations in the type I (slow muscle twitch) fibers
- these involve increasing the size and number of the mitochondria within the cell to augment aerobic adenosine triphosphate (ATP) generation
- there is a growth of more capillaries around the recruited muscle fibers, which enhances the delivery of oxygenated blood to the muscle fibers. If the recruitment is near the upper limit of a muscle fibers capacity to generate force, there may also be adaptions in the contractile mechanism (the actin and myosin filaments), leading to hypertrophy of those muscle fibers
- during higher-intensity endurance, the type II (fast twitch) muscle fibers may be recruited. They adapt primarily by increasing the number of anaerobic enzymes so that anaerobic energy production will be enhanced (may also be hypertrophy of the contractile proteins within the muscle fiber)
Fundamental Physiological Adaptations of the Cardiovascular System
- due to expansion of blood volume that occurs with endurance training, the heart muscle will hypertrophy, enlarging its chambers and becoming a bigger and stronger muscle that is able to deliver a higher cardiac output to the muscle
- these adaptions are primarily in the form of a larger stroke volume (amount of blood pumped per beat)
- maximal heart rate (MHR) does not increase with training
- increase in stroke volume is doe to chamber enlargement, greater amounts of chamber filling (end-diastolic volume), and greater chamber emptying (ejection fraction) of the heart with each beat
- some evidence that redistribution of the cardiac output to the active muscles (via vasodilation) may improve after training, thus, making the increase in cardiac output more effective in terms of delivering oxygen where it is needed
Fundamental Physiological Adaptations for Time Required for Anaerobic Power
- VO2 Max increases with training, but reaches a peak and plateaus within about 6 months
- changes in ventilatory threshold (VT), a significant marker of metabolism that permits prediction of lactate threshold (LT) from the minute ventilation (Ve) response during progressive exercise may continue for years. This change is attributed primarily to capillary growth and increase mitochondrial density (size and number) in active muscles
- to support these cardiorespiratory adaptations, the capacity of the muscle to store additional glycogen increases and the ability to mobilize and use fatty acids as a fuel source is also enhanced
Fundamental Physiological Adaptations to Steady-State and Interval-Based Training
- primary adaptations to exercise training occur during steady state exercise at moderate intensity. Steady state refers to that intensity of exercise where the energy and physiological demands of the exercise bout are met by the delivery of the physiological systems in the body
- at steady state, the rate of O2 uptake (VO2), HR, Cardiac output, ventilation, blood lactate concentration, and body temperature reach stable (although elevated) levels after a short period of exercise
- when an exercise bout begins or intensity changes, the body takes between 45s and 3-4min to achieve steady state. The time needed to achieve this level (aka “second wind”) depends on the fitness level (fitter people get to it faster) and intensity (higher intensity require longer periods to achieve it)
- interval training promotes similar or greater improvements in VO2 max and fitness than steady state exercise
- intervals provide anaerobic adaptions to improve an individual’s tolerance for the buildup of lactate that may continue to increase leg after VO2 max adaptations have reached their maximal extent. This adaptation enhances one’s ability to sustain higher intensities of exercise for longer periods
Fundamental Physiological Adaptations to Steady-State and Interval-Based Training
- primary adaptations to exercise training occur during steady state exercise at moderate intensity. Steady state refers to that intensity of exercise where the energy and physiological demands of the exercise bout are met by the delivery of the physiological systems in the body
- at steady state, the rate of O2 uptake (VO2), HR, Cardiac output, ventilation, blood lactate concentration, and body temperature reach stable (although elevated) levels after a short period of exercise
- when an exercise bout begins or intensity changes, the body takes between 45s and 3-4min to achieve steady state. The time needed to achieve this level (aka “second wind”) depends on the fitness level (fitter people get to it faster) and intensity (higher intensity require longer periods to achieve it)
- interval training promotes similar or greater improvements in VO2 max and fitness than steady state exercise
- intervals provide anaerobic adaptions to improve an individual’s tolerance for the buildup of lactate that may continue to increase leg after VO2 max adaptations have reached their maximal extent. This adaptation enhances one’s ability to sustain higher intensities of exercise for longer periods
Components of a Cardiorespiratory Workout Session: Warm-Up
- lighter exercise performed for 5-10 minutes (start low to moderate and gradually increase intensity)
- if there are higher-intensity intervals planned during the conditioning phase, the latter portion of the warmup could include some brief higher intensity exercise to prepare for that
- general rule: the harder the conditioning phase, the more extensive the warm-up should be
Components of a Cardiorespiratory Workout Session: Conditioning Phase
- should be planned in terms of frequency, duration, intensity (steady state or interval formats), and modality
- higher intensity elements should take place fairly early in this phase, and the session should be concluded with steady state exercise
- cardiovascular drift: cardiovascular phenomenon that represents a gradual increase in HR response during a steady state bout of exercise. Causes for this include: 1. small reductions in blood volume that occur during exercise die to fluid lost to sweat and fluid moving into the spaces between cells, which results in a compensatory increase in HR to maintain cardiac output, offsetting the small decrease in stoke volume (Cardiac output= HR x stroke volume) 2. increasing core temperature that directs greater quantities of blood to the skin to facilitate heat loss, consequently decreasing decreasing blood return to the heart and blood available for the excessing muscles
- aerobic interval training generally involves bouts of steady state performed at higher intensities for sustained periods (a min of 3min), followed by a return to lower aerobic intensities for the recovery interval (often utilize exercise-to-recovery ratios between 1:2 and 1:1- ex. a four minute steady followed by an 8 minute recovery with lower intensity when following a 1:2)
- higher intensity intervals of 15-30s may recruit typeII muscle fibers
Components of a Cardiorespiratory Workout Session: Cool-down
- approx. same duration and intensity as warmup (5-10min of low to moderate intensity)
- directed primarily toward preventing the tendency for blood to pool in the extremities, which may occur when exercise ends
- lack of cool down can cause blood to accumulate in lower extremity after muscle pump, reducing blood flow back to heart and out to vital organs like the brain (which could cause lightheadedness)
- active cool down helps remove metabolic waste from the muscles so that it can be metabolized by other tissues
- stretching after this can improve flexibility
General Guidelines for Cardiorespiratory Exercise For Health, Fitness, and Weight Loss: 2008 Physical Activity Guidelines for Americans by the US Department of Heath and Human Services
- Specific guidelines for ages 18-64
1. Perform 150min per week of moderate-intensity aerobic physical activity or 75min per week of vigorous-intensity aerobic activity or a combo of both
2. Additional health benefits are obtained from performing greater amounts of activity than those quantities
3. Perform aerobic bouts that last at least 10min, preferably spread throughout the week
4. Participate in muscle-strengthening activities involving all muscle major groups at least 2 days a week - Guidelines for children age 6 to 17
1. Perform at least 60min of moderate to vigorous physical activity every day
2. Include vigorous intensity activity a min of 3 days a week
3. Participate in muscle-strengthening and bone-strengthening activity a min of 3 days a week
General Guidelines for Cardiorespiratory Exercise For Health, Fitness, and Weight Loss: Physical activity guidelines from American College of Sports Medicine and the American Heart Association
-use the FITT acronym to discuss cardiovascular programming guidelines (frequency, intensity, time (duration), type)-trainers should consider putting an E on the end to represent “enjoyable” or “experience”
General Guidelines for Cardiorespiratory Exercise For Health, Fitness, and Weight Loss: Frequency
- recommend physical activity for most days of the week
- Moderate-intensity aerobic exercise (40% to 60% VO2 R or HRR)= min of 5 days a week
- Vigorous-intensity aerobic exercise (greater than or equal to VO2 R or HRR)=min of 3 days a week
- Combo of both= 3-5 days
General Guidelines for Cardiorespiratory Exercise For Health, Fitness, and Weight Loss: Intensity and HR
- measure intensity through HR (% MHR; %heart rate reserve HRR), RPE, VO2 or metabolic equivalents (METs), caloric expenditure, talk test/VT1, blood lactate and VT2
- Note: can calculate MHR through 220-age, but factors can get in the way like genetics, exercise modality (can vary based on different machines and muscles used during them), medications, body size (MHR is generally higher in smaller people who have smaller hearts/lower stroke volumes), altitude (can lower MHR reached due to inability to reach higher intensity), age
- better to use Gellish et al. formula 206.9-(0.67 x age) or Tanaka, Monahan, and Seals formula 208-(0.7 x age)
- Recommended framework for exercise intensity for apparently healthy adults:
1. Activity/Exercise Level: Sedentary/no habitual activity to exercise extremely deconditioned; Fitness Classification: Poor; %MHR 57-67%; %HRR/VO2 max or VO2R: 30-45%
2. Activity/Exercise Level: Minimal activity/no exercise, moderately to highly deconditioned; Fitness Classification: Poor/Fair; %MHR 64-74%; %HRR/VO2 max or VO2R: 40-55%
3. Activity/Exercise Level: Sporadic physical activity/no or suboptimal exercise, moderately to mildly deconditioned; Fitness Classification: Fair/Average; %MHR 74-84%; %HRR/VO2 max or VO2R: 55-70%
4. Activity/Exercise Level: Habitual physical activity/regular moderate to vigorous intensity; Fitness Classification: Average/Good; %MHR 80-91%; %HRR/VO2 max or VO2R: 65-80%
5. Activity/Exercise Level: High amounts of habitual activity/regular vigorous-intensity exercise; Fitness Classification: Good/Excellent; %MHR 84-94%; %HRR/VO2 max or VO2R: 70-85%
General Guidelines for Cardiorespiratory Exercise For Health, Fitness, and Weight Loss: Karvonen Formula
-aka HR reserve formula
Target HR (THR) = (HRR x % Intensity) + RHR Where: HRR = MHR - RHR
General Guidelines for Cardiorespiratory Exercise For Health, Fitness, and Weight Loss: Ratings of Perceived Exertion
two scales to measure intensity subjectively
- the classical 6 to 20 scale
- more contemporary 0 to 10 scale
General Guidelines for Cardiorespiratory Exercise For Health, Fitness, and Weight Loss: VO2 or metabolic equivalents
many studies have shown that there are minimal improvements in VO2max if the intensity of training is below a threshold of 40/50% of VO2max or VO2R (reserve)
-overall, its not not very effective to use this to measure intensity
-METs: multiples of an assumed average metabolic rate at rest of 3.5mL/kg/min (good to note, though, that not everyone’s rest rate is this)
Examples:
LIGHT (<3 METs)=
1. Walking-walking slowly around home or store
2. Household and occupation-sitting, light hand tools, standing doing light work, making bed, cooking, dishes, etc.
3. Leisure time and sports- arts and crafts, cards, boating, croquet, playing instruments
MODERATE (3-6 METs)
1. Walking- walking 3mph or briskly 4mph
2. Household and occupation-cleaning, heavy, washing windows/car/garage, sweeping floors, vacuuming, stacking wood, mowing lawn
3. Leisure time and sports-basketball (shooting around), dancing (ballroom), badminton, cycling on flat 10-12mph, table tennis
VIGOROUS (>6 METs)
1. Walking, jogging, and running-walking very, very brisk 4.5 mph, walking/hiking at moderate pace with or without light pack, hiking at steep grades, jogging at 5mph, at 6mph, running at 7mph
2. Household and occupation-shoveling sand, coal, carrying bricks, heavy farming, digging ditches
3. Leisure time and sports-basketball game, soccer, swimming, volleyball competitive
