Adaptations to Aerobic and

Anaerobic Training

Adaptations to Aerobic Training:Adaptations to Aerobic Training:Cardiorespiratory EnduranceCardiorespiratory Endurance

• Cardiorespiratory endurance– Ability to sustain prolonged, dynamic exercise– Improvements achieved through multisystem

adaptations (cardiovascular, respiratory, muscle, metabolic)

• Endurance training– Maximal endurance capacity = VO2max

– Submaximal endurance capacity• Lower HR at same submaximal exercise intensity• More related to competitive endurance

performance

Figure 11.1Figure 11.1

Adaptations to Aerobic Training:Adaptations to Aerobic Training:Major Cardiovascular ChangesMajor Cardiovascular Changes

• Heart size• Stroke volume• Heart rate• Cardiac output• Blood flow• Blood pressure• Blood volume

Adaptations to Aerobic Training:Adaptations to Aerobic Training:CardiovascularCardiovascular

• O2 transport system and Fick equation– VO2 = SV x HR x (a-v)O2 difference

– VO2max = max SV x max HR x max (a-v)O2 difference

• Heart size– With training, heart mass and LV volume – Target pulse rate (TPR) cardiac hypertrophy

SV– Plasma volume LV volume EDV

SV– Volume loading effect

Adaptations to Aerobic Training:Adaptations to Aerobic Training:CardiovascularCardiovascular

• SV after training– Resting, submaximal, and maximal– Plasma volume with training EDV

preload– Resting and submaximal HR with training

filling time EDV– LV mass with training force of contraction– Attenuated TPR with training afterload

• SV adaptations to training with age

Figure 11.3Figure 11.3

Table 11.1Table 11.1

Adaptations to Aerobic Training:Adaptations to Aerobic Training:CardiovascularCardiovascular

• Resting HR– Markedly (~1 beat/min per week of training)– Parasympathetic, sympathetic activity in heart

• Submaximal HR– HR for same given absolute intensity– More noticeable at higher submaximal intensities

• Maximal HR– No significant change with training– With age

Figure 11.4Figure 11.4

Adaptations to Aerobic Training:Adaptations to Aerobic Training:CardiovascularCardiovascular

• HR-SV interactions– Does HR SV? Does SV HR?– HR, SV interact to optimize cardiac output

• HR recovery– Faster recovery with training– Indirect index of cardiorespiratory fitness

• Cardiac output (Q)– Training creates little to no change at rest,

submaximal exercise– Maximal Q considerably (due to SV)

Figure 11.5Figure 11.5

Figure 11.6Figure 11.6

Adaptations to Aerobic Training:Adaptations to Aerobic Training:CardiovascularCardiovascular

• Blood flow to active muscle

• Capillarization, capillary recruitment– Capillary:fiber ratio– Total cross-sectional area for capillary exchange

• Blood flow to inactive regions

• Total blood volume – Prevents any decrease in venous return as a result

of more blood in capillaries

Adaptations to Aerobic Training:Adaptations to Aerobic Training:CardiovascularCardiovascular

• Blood pressure– BP at given submaximal intensity– Systolic BP, diastolic BP at maximal intensity

• Blood volume: total volume rapidly– Plasma volume via plasma proteins, water

and Na+ retention (all in first 2 weeks)– Red blood cell volume (though hematocrit may

)– Plasma viscosity

Cardiovascular Adaptations to Cardiovascular Adaptations to Chronic Endurance ExerciseChronic Endurance Exercise

Adaptations to Aerobic Training:Adaptations to Aerobic Training:RespiratoryRespiratory

• Pulmonary ventilation– At given submaximal intensity– At maximal intensity due to tidal volume and

respiratory frequency• Pulmonary diffusion

– Unchanged during rest and at submaximal intensity– At maximal intensity due to lung perfusion

• Arterial-venous O2 difference– Due to O2 extraction and active muscle blood

flow– O2 extraction due to oxidative capacity

Adaptations to Aerobic Training:Adaptations to Aerobic Training:MuscleMuscle

• Fiber type– Size and number of type I fibers (type II type I)– Type IIx may perform more like type IIa

• Capillary supply– Number of capillaries supplying each fiber– May be key factor in VO2max

• Myoglobin– Myoglobin content by 75 to 80%– Supports oxidative capacity in muscle

Adaptations to Aerobic Training:Adaptations to Aerobic Training:MuscleMuscle

• Mitochondrial function– Size and number– Magnitude of change depends on training volume

• Oxidative enzymes (SDH, citrate synthase)– Activity with training– Continue to increase even after VO2max plateaus– Enhanced glycogen sparing

Adaptations to Aerobic Training:Adaptations to Aerobic Training:MuscleMuscle

• High-intensity interval training (HIT): time-efficient way to induce many adaptations normally associated with endurance training

• Mitochondrial enzyme cytochrome oxidase (COX) same after HIT versus traditional moderate-intensity endurance training

Adaptations to Aerobic Training:Adaptations to Aerobic Training:MetabolicMetabolic

• Lactate threshold– To higher percent of VO2max

– Lactate production, lactate clearance– Allows higher intensity without lactate accumulation

• Respiratory exchange ratio (RER)– At both absolute and relative submaximal

intensities– Dependent on fat, dependent on glucose

Figure 11.10Figure 11.10

Adaptations to Aerobic Training:Adaptations to Aerobic Training:MetabolicMetabolic

• Resting and submaximal VO2

– Resting VO2 unchanged with training

– Submaximal VO2 unchanged or slightly with training

• Maximal VO2 (VO2max)– Best indicator of cardiorespiratory fitness– Substantially with training (15-20%)– Due to cardiac output and capillary density

Table 11.3Table 11.3

Table 11.3 Table 11.3 (continued)(continued)

Adaptations to Aerobic Training:Adaptations to Aerobic Training:MetabolicMetabolic

• Long-term improvement– Highest possible VO2max achieved after 12 to 18

months– Performance continues to after VO2max plateaus

because lactate threshold continues to with training

• Individual responses dictated by– Training status and pretraining VO2max

– Heredity

Adaptations to Aerobic Training:Adaptations to Aerobic Training:MetabolicMetabolic

• Training status and pretraining VO2max

– Relative improvement depends on fitness– The more sedentary the individual, the greater the – The more fit the individual, the smaller the

• Heredity– Finite VO2max range determined by genetics, training

alters VO2max within that range

– Identical twin’s VO2max more similar than fraternal’s

– Accounts for 25 to 50% of variance in VO2max

Adaptations to Aerobic Training:Adaptations to Aerobic Training:MetabolicMetabolic

• Sex– Untrained female VO2max < untrained male VO2max

– Trained female VO2max closer to male VO2max

• High versus low responders– Genetically determined variation in VO2max for same

training stimulus and compliance– Accounts for tremendous variation in training

outcomes for given training conditions

Adaptations to Aerobic Training:Adaptations to Aerobic Training:Fatigue Across SportsFatigue Across Sports

• Endurance training critical for endurance-based events

• Endurance training important for non-endurance-based sports, too

• All athletes benefit from maximizing cardiorespiratory endurance

Adaptations to Anaerobic TrainingAdaptations to Anaerobic Training

• Changes in anaerobic power and capacity– Wingate anaerobic test closest to gold standard for

anaerobic power test– Anaerobic power and capacity with training

• Adaptations in muscle– In type IIa, IIx cross-sectional area– In type I cross-sectional area (lesser extent)– Percent of type I fibers, percent of type II

Adaptations to Anaerobic TrainingAdaptations to Anaerobic Training

• ATP-PCr system– Little enzymatic change with training– ATP-PCr system-specific training strength

• Glycolytic system– In key glycolytic enzyme activity with training

(phosphorylase, PFK, LDH, hexokinase)– However, performance gains from in strength

Specificity of Training Specificity of Training and Cross-Trainingand Cross-Training

• Specificity of training– VO2max substantially higher in athlete’s sport-specific

activity– Likely due to individual muscle group adaptations

• Cross-training– Training different fitness components at once or

training for more than one sport at once– Strength benefits blunted by endurance training– Endurance benefits not blunted by strength training