88C H A P T E R

Physiological Adaptations to Anaerobic and Aerobic Endurance Training Programs

Physiological Adaptations to Anaerobic and Aerobic Endurance Training Programs

William J. Kraemer

Chapter Outline

Anaerobic training

Detraining

Endocrine responses to anaerobic and aerobic exercise

Aerobic endurance exercise training

Overtraining

Performance gains typically are related to

changes in more than one physiological system.

The training program must train each

physiological system in careful balance with

specific performance goals in mind.

Key Concepts of Physiological Adaptations to Exercise Training

Each person responds differently to each training program.

There is a psychological component to training.

The magnitude of the physiological or performance gain is related to the size of an athlete’s adaptational window.

The amount of physiological adaptation depends on the effectiveness of the exercise prescriptions used in the training program.

Training for peak athletic performance is different from training for optimal health and fitness.

Relationship Between Energy Delivery Systems and Exercise DurationRelationship Between Energy Delivery Systems and Exercise Duration

Anaerobic Training: Two Primary Energy Systems

The phosphagen system provides immediate ATP energy for fast and powerful movements. This system is used during short-duration, high-intensity activities with long rest periods.

The glycolytic system breaks down glucose to lactic acid and is the next most readily available source of ATP. This system is used during longer, less intense exercise with shorter rest periods.

The oxidative system also plays a role in maintaining power output and recovering energy stores.

Table 8.2 Comparison of Physiological Adaptations to Resistance Training and Aerobic Endurance Training

Variable Results following Results following aerobicresistance training endurance training

Performance

Muscle strength Increases No change

Muscle endurance Increases for high power Increases for low poweroutput output

Aerobic power No change or increases Increasesslightly

Maximal rate of Increases No change or decreasesforce production

Vertical jump Ability increases Ability unchanged

Anaerobic power Increases No change

Sprint speed Improves No change or improvesslightly

(continued)

Table 8.2 (continued)

Variable Results following Results following aerobicresistance training endurance training

Muscle fibers

Fiber size Increases No change or increases slightly

Capillary density No change or decreases Increases

Mitochondrial Decreases Increasesdensity

Fast heavy-chain Increases in amount No change or decreasesmyosin in amount

Type II muscle Almost all to Type IIa With spring interval, afiber subtype majority to Type IIaconversion

(continued)

Table 8.2 (continued)

Variable Results following Results following aerobicresistance training endurance training

Enzyme activity

Creatine Increases Increasesphosphokinase

Myokinase Increases Increases

Phospho- Increases Variablefructokinase

Lactate No change or variable Variabledehydrogenase

(continued)

Table 8.2 (continued)

Variable Results following Results following aerobicresistance training endurance training

Metabolic energy stores

Stored ATP Increases Increases

Stored creatine Increases Increasesphosphate

Stored glycogen Increases Increases

Stored May increase Increasestriglycerides

(continued)

Table 8.2 (continued)

Variable Results following Results following aerobicresistance training endurance training

Connective tissue

Ligament strength May increase Increases

Tendon strength May increase Increases

Collagen content May increase Variable

Bone density No change or increases No change or increases

Body composition

% body fat Decreases Decreases

Fat-free mass Increases No change

Graphic Representation of the Size PrincipleGraphic Representation of the Size Principle

With heavy resistance training, all muscle

fibers get bigger because they are all recruited

in consecutive order by their size to produce

high levels of force. In advanced lifters, the

central nervous system might adapt by allowing

these athletes to recruit some motor units not in

consecutive order, but by recruiting larger ones

first to help with greater production of power or

speed in a movement.

Changes in Muscle Fiber SubtypesChanges in Muscle Fiber Subtypes

RM Continuum of Training EffectsRM Continuum of Training Effects

Theoretical Interplay Between Neural and Muscle-Tissue Factors

Theoretical Interplay Between Neural and Muscle-Tissue Factors

Incorporating resistance training into an

aerobic endurance training program can

improve the ability of the heart, lungs, and

circulatory system to function under conditions

of high pressure and force production.

Resistance exercise, however, is not effective in

increasing maximal oxygen consumption.

Endocrine Responses to Anaerobic and Aerobic Exercise

During high-intensity exercise, the concentrations of hormones in blood and other body fluids can increase 10 to 20 times over their levels at rest. Exercise-induced mechanisms contribute to changes in hormone concentrations, including

changes in clearance rates in the liver,

shifts in blood volume,

receptor interactions.

hormone degradation, and

Results of Aerobic Endurance Exercise Training

Reduced body fat

Increased maximal oxygen uptake

Increased respiratory capacity

Lower blood lactate concentrations

Increased mitochondrial and capillary densities

Improved enzyme activity

Combining resistance and

aerobic endurance activities

appears to interfere primarily with

strength and power performances.

Responses of Muscle Fibers With Maximal Simultaneous Training for Strength and Endurance

Responses of Muscle Fibers With Maximal Simultaneous Training for Strength and Endurance

Overtraining (defined as excessive

frequency, volume, or intensity of training,

resulting in fatigue) can cause dramatic

performance decreases in athletes of all

training levels.

Markers of Anaerobic Overtraining

Psychological effects: decreased desire to train; decreased joy from training

Acute epinephrine and norepinephrine increases beyond normal exercise-induced levels

Performance decrements, although these occur too late to be a good predictor

Markers of Aerobic Overtraining

Decreased performance

Decreased percentage of body fat

Decreased maximal oxygen uptake

Altered blood pressure

Increased muscle soreness

Decreased muscle glycogen

Altered resting heart rate

Increased submaximal exercise heart rate

Decreased lactate

(continued)

Markers of Aerobic Overtraining (continued)

Increased creatine kinase

Altered cortisol concentration

Decreased total testosterone concentration

Decreased ratio of total testosterone to cortisol

Decreased ratio of free testosterone to cortisol

Decreased ratio of total testosterone to sex hormone-binding globulin

Decreased sympathetic tone

Increased sympathetic stress response

Relative Responses of Physiological Variables to Training and Detraining

Relative Responses of Physiological Variables to Training and Detraining