Aerobic Training Adaptations

Adaptations to Aerobic Training

• Aerobic training induces metabolic and physiological adaptations.
• VO2max increases.
• Increases in mitochondrial density and energy-based enzymes improve muscle energy production
• Cardio-respiratory adaptations improves.
• Overall function improves in clinical populations.
• Muscular strength may increase for low power output.
• Muscular endurance may increase based on initial fitness.
• Aerobic power either doesn't change or decreases.
• Maximal rate of force either doesn't change or decreases.
• Vertical jump, anaerobic power, and sprint speed are unchanged.
• Fibre size either doesn't change or increases slightly.
• Capillary and mitochondrial density increase.
• Myofibrillar packing density and volume are unchanged.
• Cytoplasmic density is unchanged.
• MHC protein either doesn't change or decreases in amount.
• Aerobic training can increase VO2max by 5-30%.
• VO2 equals cardiac output multiplied by the arterial-venous oxygen difference.
• Stroke Volume increases with training
• Oxygen extraction increases with training.
• Capillarization increases.
• The amount of oxygen extracted increases with the number of mitochondria.
• The diffusion distance for oxygen and substrates decreases.
• Aerobically trained individuals extract and use oxygen better than untrained individuals.

Metabolic Response to Endurance Training

• Glycolysis decreases in trained individuals compared to sedentary individuals.
• CHO utilization decreases.
• Net glycogen degradation decreases.
• PCr hydrolysis decreases.
• ATP degradation products decrease, including ADP, Pi, AMP, and IMP.
• Blood lactate accumulation decreases.
• Fat oxidation increases.
• Mitochondrial enzyme activity is higher in trained individuals.
• Trained individuals have higher resting glycogen levels.
• Trained individuals exhibit less glycogen depletion after training.
• Blood glucose is spared through metabolic control.
• Blood lactate is reduced at the same intensity of exercise with training.
• Lactate threshold and OBLA both increase.
• Lactate accumulation decreases through metabolic control.
• ATP degradation products are lower following endurance training.
• Aerobic training leads to tighter metabolic control with more mitochondria.
• Lower ADP concentration changes are needed to stimulate oxidative phosphorylation.
• Aerobic energy production activates sooner at the start of exercise.
• Increased FFA oxidation leads to decreased need for ATP-PCr & glycolysis.
• Citrate production from FFA inhibits PFK.
• Pyruvate and lactate production decrease.
• More pyruvate aerobically converts.
• NADH moves into mitochondria effectively.
• Less lactate is produce, resulting in less inhibition on lipolysis.

Designing Programs

• Adaptations to exercise depends on a cardiorespiratory prescription

Designing Exercise Programs

• Client's needs and goals must be considered.
• Needs and goals related to considerations like health, performance/fitness (sport-specific), rehabilitation, or a combination.
• Client assessments and baseline fitness must be considered.
• Previous and current activities and experiences influence program design.
• Injuries or conditions affect the design of the program.
• A healthy, active 24 hours should include a variety of physical activity types and intensities:
• 150 minutes per week of moderate to vigorous aerobic exercise
• Muscle strengthening activities at least twice a week using major muscle groups
• Several hours of light physical activities, including standing
• 7 to 9 hours of good-quality sleep on a regular basis with consistent bed and wake-up times needed.
• Limiting sedentary time to 8 hours or less:
• Recreational exercise is capped at 3 hours per day
• Break up long periods of sitting as often as possible

Elements of a Cardiorespiratory Exercise Workout

• Warm-up: to minimize injury & abnormal cardiac rhythms.
• The heart rate, blood flow to muscles, and body temperature elevate.
• A 5-10 minute warm up at low to moderate intensity is recommended.
• Endurance conditioning consists of 20-60 minutes per day in bouts of 10 minutes or greater.
• Cool-down: allows the body returns to baseline & recover.
• Continue at low intensity for 5-10 min, along with flexibility exercises to reduce blood flow.
• A cool down will lower the heart rate & blood pressure to baseline, prevents pooling, reduces risk of dizziness and fainting and speed recovery, increasing lactate uptake and decreasing DOMS.

FITT-VP Principle - Elements of the Cardiorespiratory Prescription

• Frequency: Exercising greater than 3-5 days/week is recommended.
• Intensity: Exercise at a moderate, vigorous or both.
• Time: Moderate exercise for 30-60 minutes/session; Vigorous exercise for 20-60 min/session or combo.
• Type: Aerobic exercise done in a continuous or intermittent manner using large muscle groups is recommended.
• Volume: Greater than 500-1,000 MET min/wk, exceeding 7,000 steps/day, is suggested.
• 3,000 steps/day are to be covered at a brisk pace (exceeding 3METs/100 steps/min).
• Progression: Gradually adjusts the prescription.

Elements of Prescription - Frequency

• Frequency relates to the total number of sessions per week.
• Frequency depends on exercise duration, intensity, goals, client preference, and client fitness level.
• Exercise type affects frequency.
• Frequency also depends on interval training, steady-state, etc.

Elements of Prescription - Intensity

• Exercise intensity dictates the improvements that occur.
• Intensity depends on client (age, fitness level, preferences).
• Poor CRF: 30-45% VO2R is recommended.
• Most people: 55-80% VO2R is needed.
• Highly fit: Greater than 70% VO2R is suggested.
• Prescribed exercise intensity has to be lower than the intensity of assessment.

Elements of Prescription - Time and Type

• Duration is typically inversely related with intensity.
• A client should perform exercise for less than or equal to 60 minutes.
• Duration is increased before intensity during initial programming stages.
• Activity type must be considered.
• Activity type should be specific for optimal fitness outcomes or the clients goal.
• Clients interests should be reflected during program design.
• It's often necessary to implement multiple activities to achieve goals.

Elements of Prescription - Exercise

• Group A exercises: endurance activities needing minimal skill or physical fitness to perform, like walking, cycling, and dancing.
• Group B exercises: vigorous intensity endurance activities needing minimal skill, like jogging, rowing, or elliptical training.
• Group C exercises: endurance activities needing skill to perform, like swimming, cross-country skiing and skating.
• Group D exercises: recreational sports performed by adults with a regular exercise program, such as racket sports, basketball, skiing, and hiking.

Elements of Prescription - Volume

• Calculating volume
• Determined by the frequency x duration x intensity.
• Expresses as MET·min/wk or kcal/wk.
• MET-min equals the number of minutes of exercise at a given MET.
• To calculate the volume per session, a person runs at a speed corresponding to 7 METs for 30 minutes, which is 7 METS x 30 min = 210 MET-min
• Example: If you do this 5 days/week, the volume per week is 210 MET-min x 5 sessions/week, equaling 1,050 MET·min/wk.

Elements of Prescription - Volume & Energy Expenditure

• Express volume relative to energy expenditure.
• First, convert METS to VO2 expressed in mL/kg/min
• 1 MET equals 3.5 ml/kg/min.
• Second, convert oxygen consumption to L per minute: L O2 consumed/min = VO2 (in ml/kg/min) x body weight divided by 1000mL/L
• Third, convert oxygen consumption to energy expenditure in kcal per minute, where 1 L O2 consumed = 5 kcal.
• Consequently, kcal/min = L O2 consumed/min x 5 kcal/L O2.
• Lastly, energy expenditure is estimated by multiplying energy expenditure rate (kcal/min) by the length of exercise (min).

Elements of Prescription - Progression

• Progressive overload applies, and periodic increases in duration, intensity and frequency are required.
• Adaptations must occur one element at a time and gradually.
• Duration should be increased before intensity in older clients or beginners.

Stages of Programming

• Progression is split into 3 stages: initial, improvement, and Maintenance.

Stages of Progression - Initial Conditioning

• Initial conditioning: 4-6 weeks of familiarization with training and avoid injury.
• Must become part of routine; though avoided with non-beginners who are adjusted to the planned type of exercise.
• 55-60% HRR at 3 or more days a week is recommended.
• Aim for around 30 minutes a week and progress as soon as this is reached.

Stages of Progression - Improvement & Maintenance

• Improvement: this stage consists of progressing over 4-8 months.
• Develop a planned method and systematic method of progression for duration, intensity, frequency, and overload.
• Prioritize increases in duration or frequency before intensity.
• Increase duration based on the 10% rule.
• Increase frequency to 4-5 days per week.
• Increase intensity once desired duration and frequency are reached.
• Intensity cannot increase more than 5% HRR every 6th session (ACSM).
• Continue until goal is reached where VO2max may increase by 5-20% average.
• Improvements relies on initial fitness, age, and health, from 5% to 40% improvement.
• Older adults show slower rates of improvement.
• Maintenance: the level of fitness achieved at end of improvement is maintained.
• Long-term progression is beneficial to maintain goal activity that's 2-3 days per week performing the same efforts or the same.

Components of Well Rounded Routine

• Beginners should aim for 3 days a week
• 30-45% VO2R should be the starting intensity
• Group A type exercises are recommended and should progress to 55-60% VO2R.
• Aim for 15-20 minutes to start
• Progress to 30min/session.

Methods to Monitor Exercise Intensity

• Heart rate (%HRmax or %HRR)
• Percent VO2max or % VO2 Reserve
• Exercise velocity/work rate
• Ratings of Perceived Exertion (RPE)
• Monitoring intensity is important to maintain the stimulus, improve and monitor motivation, and track comparisons in training.

Prescribing Exercise Intensity using Heart Rate (HR)

• HRmax refers to Maximal Heart Rate
• HRR refers to Heart Rate Reserve
• HR indicates exercise capacity during cardiorespiratory endurance
• HR metrics are relevant during light, moderate, vigorous activity
• Max HR may be achieved before VO2 max.
• A rating on the Rate of Perceived Exertion Scale can also determine exercise output
• % HR max is always higher than %VO2 max.
• Heart rate is a linear function of exercise intensity.
• Typical range of intensity is 60-90% HRmax.
• An assumed Max HR of 200 bpm and Training Intensity of 75% results in THR75 = 150 bpm
• Karvonen Method calculates THR is calculated by THR = % exercise intensity x HRR + HRrest
• Max HR, medication, environment and variability in max HR contribute to the affect HR performance

High Intensity Training

• High Intensity Intermittent Training should perform activity 1-2 times per week
• Performance should be near maximal for 1-4 minutes
• The above metrics improve endurance, lactate threshold, VO2 max and anaerobic metabolism

Sprint Training

• Sprint Interval Training should perform high reliance activity 1 day per week
• Intensity activity is greater then VO2 max
• Maintain duration of 30-90 seconds

Fartlek Training

• Fartlek Training is a Swedish approach of "speed play"
• It is a Form of interval training
• Training varies a client's workrate throughout the workout for 5-90% VO2R

Effects of Concurrent Training

• Training adaptations are specific stimulus
• Combined training has adverse effects on Heavy Restraints and mRNA
• Concurrent training is beneficial for a variety of activity
• VO2 max has increased effect in untrained and trained settings