Strength and Conditioning Week 18
Cardiorespiratory training
CONDITIONING EXERCISES WHICH COLLECTIVELY STRESS THE CARDIAC, VASCULAR,
RESPIRATORY AND METABOLIC SYSTEMS AND MANIFEST SPECIFIC ADAPTATIONS
THROUGH CHANGES IN FREQUENCY, VOLUME, INTENSITY AND RECOVERY OF
TRAINING INTERVENTIONS
Primary energy systems
● ATP-PCR system
● Anaerobic glycolytic
● Aerobic (oxidative) system
The myosin filament within a muscle myofibril binds to ATP and releases an enzyme ATPase
which hydrolyses ATP into ADP and a phosphate group producing energy
The ATP-PCr system is predominant in the first 10 seconds of exercise activity. ATP in muscle
tissue is extremely limited and the human body contains around 40-50g which could sustain 2-4
seconds of high intensity exercise.
The human body needs to be able to constantly resynthesize ATP. ADP can be reformed back
into ATP immediately by phosphocreatine (PCr) which donates its phosphate in the presence of
another enzyme creatine kinase de-phosphorylating into creatine.
Creatine can be re-phosphorylated into PCr by ATP produced in the mitochondria during
aerobic recovery in the presence of oxygen. This process is enhanced when blood flow is
maximised to the muscle cells as a consequence this is why the need for active recovery is
crucial between high intensity bouts.
,The anaerobic glycolytic system is predominant from 10-45 seconds of exercise activity. During
this phase of muscular contraction ADP can be reformed back into ATP by muscle glycogen
and (to some extent) blood glucose.
This process has number of by products associated with it most notably lactic acid and lactate
(which are not the same thing). When lactic acid is produced it is quickly ionized and releases a
hydrogen ion which in turn causes muscular acidosis. The remaining compound by product,
lactate, can be shuttled between tissues and used to resynthesize ATP.
The aerobic/oxidative system is predominant from 45+ seconds of exercise activity. During this
phase of muscular contraction ADP can be reformed back into ATP the complete oxidation of
glucose and free fatty acids in the presence of oxygen within the mitochondria.
Aerobic activities occur at much lower exercise intensity due to the fact that the rate of ATP
production via CHO and lipid metabolism is much slower than the previous two systems.
, The 3 energetic pathways for skeletal muscular contraction are highly dependant on duration
and intensity of the exercise performed.
This is not only regulated by the above but also the amount of time each process takes to
produce ATP. PCr generation of ATP is a singular reaction, anaerobic glycolysis entails 10
reactions whereas the aerobic system requires 26 reactions for glucose oxidation and 90-100
reactions for fatty acid oxidation.
Cardiorespiratory training
CONDITIONING EXERCISES WHICH COLLECTIVELY STRESS THE CARDIAC, VASCULAR,
RESPIRATORY AND METABOLIC SYSTEMS AND MANIFEST SPECIFIC ADAPTATIONS
THROUGH CHANGES IN FREQUENCY, VOLUME, INTENSITY AND RECOVERY OF
TRAINING INTERVENTIONS
Primary energy systems
● ATP-PCR system
● Anaerobic glycolytic
● Aerobic (oxidative) system
The myosin filament within a muscle myofibril binds to ATP and releases an enzyme ATPase
which hydrolyses ATP into ADP and a phosphate group producing energy
The ATP-PCr system is predominant in the first 10 seconds of exercise activity. ATP in muscle
tissue is extremely limited and the human body contains around 40-50g which could sustain 2-4
seconds of high intensity exercise.
The human body needs to be able to constantly resynthesize ATP. ADP can be reformed back
into ATP immediately by phosphocreatine (PCr) which donates its phosphate in the presence of
another enzyme creatine kinase de-phosphorylating into creatine.
Creatine can be re-phosphorylated into PCr by ATP produced in the mitochondria during
aerobic recovery in the presence of oxygen. This process is enhanced when blood flow is
maximised to the muscle cells as a consequence this is why the need for active recovery is
crucial between high intensity bouts.
,The anaerobic glycolytic system is predominant from 10-45 seconds of exercise activity. During
this phase of muscular contraction ADP can be reformed back into ATP by muscle glycogen
and (to some extent) blood glucose.
This process has number of by products associated with it most notably lactic acid and lactate
(which are not the same thing). When lactic acid is produced it is quickly ionized and releases a
hydrogen ion which in turn causes muscular acidosis. The remaining compound by product,
lactate, can be shuttled between tissues and used to resynthesize ATP.
The aerobic/oxidative system is predominant from 45+ seconds of exercise activity. During this
phase of muscular contraction ADP can be reformed back into ATP the complete oxidation of
glucose and free fatty acids in the presence of oxygen within the mitochondria.
Aerobic activities occur at much lower exercise intensity due to the fact that the rate of ATP
production via CHO and lipid metabolism is much slower than the previous two systems.
, The 3 energetic pathways for skeletal muscular contraction are highly dependant on duration
and intensity of the exercise performed.
This is not only regulated by the above but also the amount of time each process takes to
produce ATP. PCr generation of ATP is a singular reaction, anaerobic glycolysis entails 10
reactions whereas the aerobic system requires 26 reactions for glucose oxidation and 90-100
reactions for fatty acid oxidation.
