Cardiorespiratory adaptations to aerobic training include increased cardiac output and oxygen delivery through enlarged chambers, thicker walls, and higher stroke volume. Respiratory adaptations include higher tidal volumes and pulmonary diffusion. Metabolic adaptations include increased lactate threshold and utilization of fatty acids through enhanced oxidative enzymes and mitochondria. Resistance training provides some cardiovascular benefits like lower resting heart rate and blood pressure while negatively impacting aerobic endurance abilities. Factors like heredity, age, gender, and training specificity influence the degree of adaptation.

1. Cardiorespiratory Adaptations to
Training
-Dr. Diksha Gondkar, MPT (Neuro)

2. Cardiovascular Adaptations
From Aerobic Training
 Increased cardio-respiratory endurance
 Increased muscular endurance
 Decreased VO2 at rest and submaximal exercise
 IncreasedVO2 Max
 Increased heart weight, volume, and chamber size
 Increased left ventricle wall thickness “athletes heart”
 Increased left ventricle EDV
 Increased blood plasma
 Increased Stroke Volume
 from increased EDV and decreased ESV = increased EF
 Frank-Starling law: elastic recoil of the ventricle

3. Cardiovascular Adaptations
From Aerobic Training
 Decreased resting heart rate
 from increased parasympathetic activity and decreased
sympathetic activity.
 Decreased submaximal heart rate
 Decreased maximum heart rate of elite athletes
 if your heart rate is too fast the period of ventricular filling is
reduced and your stroke volume might be compromised.
 the heart expends less energy by contracting less often but
more forcibly than it would by contracting more often.
 Decreased Heart Rate Recovery

4. Cardiovascular Adaptations
From Aerobic Training
 Maintained cardiac output at rest and submaximal
exercise
 Increased cardiac output during maximal exercise
 Increased blood flow to the muscles
 increased capillarization of trained muscles
 greater opening of existing capillaries in trained muscles
 more effective blood redistribution
 increased blood volume
 decreased blood viscosity & increased oxygen delivery
 Decreased resting blood pressure, but is unchanged
during exercise
 from increased blood flow

5. Cardiovascular Adaptations
From Aerobic Training
 Increased blood volume (blood plasma) and is greater
with more intense levels of training
 increased release of antidiuretic hormone
 increased plasma proteins which help retain blood fluid
 increased red blood cell volume
 decreased blood viscosity

6. Respiratory Adaptations From
Aerobic Training
 Respiratory system functioning usually does not
limit performance because ventilation can be
increased to a greater extent than cardiovascular
function.
 Slight increase in Total lung Capacity
 Slight decrease in Residual Lung Volume
 Increased Tidal Volume at maximal exercise levels
 Decreased respiratory rate and pulmonary
ventilation at rest and at submaximal exercise
 (RR) decreases because of greater pulmonary efficiency
 Increased respiratory rate and pulmonary ventilation
at maximal exercise levels
 from increased tidal volume – Inc max O2 consumption

7. Respiratory Adaptations From
Aerobic Training
 Unchanged pulmonary diffusion
at rest and submaximal exercise.
 Increased pulmonary diffusion
during maximal exercise.
 from increased circulation and
increased ventilation
 from more alveoli involved during
maximal exercise
 Increased A-VO2 difference
especially at maximal exercise.

8. Metabolic Adaptations From
Aerobic Training
 Lactate threshold occurs at a higher percentage of
VO2 Max.
 from a greater ability to clear lactate from the muscles
 from an increase in skeletal muscle enzymes
 Decreased Respiratory Exchange Ratio (ratio of
carbon dioxide released to oxygen consumed)
 from a higher utilization of fatty acids instead of carbs
 however, the RER increases from the ability to perform at
maximum levels of exercise for longer periods of time
because of high lactate tolerance.
 Increased resting metabolic rate
 Decreased VO2 during submaximal exercise
 from a metabolic efficiency and mechanical efficiency

9. Metabolic Adaptations From
Aerobic Training
 Large increases in VO2 Max
 in mature athletes, the highest attainable VO2 Max is
reached within 8 to 18 months of heavy endurance
training.
 VO2 Max is influenced by “training” in early
childhood.
 from increased oxidative enzymes
 from increased size and number of mitochondria
 from increased blood volume, cardiac output & O2
diffusion
 from increased capillary density

10. Cardiorespiratory Adaptations
From Anaerobic Training
 Small increase in cardiorespiratory endurance
 Small increase in VO2 Max
 Small increases in Stroke Volume

11. Cardiorespiratory Adaptations
From Resistance Training
 Small increase in left ventricle size
 Decreased resting heart rate
 Decreased submaximal heart rate
 Decreased resting blood pressure is greater than from
endurance training
 Resistance training has a positive effect on aerobic
endurance but aerobic endurance has a negative
effect on strength, speed and power.
 muscular strength is decreased
 reaction and movement times are decreased
 agility and neuromuscular coordination are decreased
 concentration and alertness are decreased

12. Factors Affecting the
Adaptation to Aerobic
Training
 Heredity accounts for between 25% and 50% of the
variance in VO2 Max values.
 Age-Related decreases in VO2 Max might partly
result from an age-related decrease in activity levels.
 Gender plays a small role (10% difference) in the VO2
Max values of male and female endurance athletes.
 There will be RESPONDERS (large improvement)
and NONRESPONDERS (little improvement) among
groups of people who experience identical training.
 The greater the Specificity of Training for a given
sport or activity, the greater the improvement in
performance.

13. Bibliography
 Cardiovascular adaptations to exercise and training.
Vet Clin North Am Equine Pract. 1985 Dec;1(3):513-
31.
 Physiology of Sport and Exercise Jack Wilmore,
David Costill 3rd Edition 2004
 CARDIOVASCULAR ADAPTATIONS by M. Doug
McGuff, M.D.