Phys Exam III Exercise

muscle need atp for crossbridge movement, Ca2+ reuptake , and for Na+K+ ATPase

phosphocreatine

Anaerobic glycolysis

Beta-oxidation

• glycolytic
• anerobic "white"
• large diameter fibers
• Fewer blood vessels
• Little myoglobin

• Red
• Intermediate

• oxidative
• small diameter
• many blood vessels
• high myoglobin

• Increases fat and glycogen stores within muscle
• Increases the activity of Beta-oxidation enzymes
• CHanges the relative composition of muscle fibers

Continued oxygen consumption after exercise stops

• Metabolize lactate
• Restore muscle ATP
• Restore phosphcreatine
• Replenish myoglobin O2

is an estimated of the maximum sustained oxygen consumption

The ratio of VO2max to oxygen consumption at rest

10

• LOW pO2
• LOW pH
• HIGH pCO2
• sensed by the glomus cells
• high [H+] sensed by central chemoreceptor

Increase lactate threshold, which is the exercise intensity where lactate will accumulate in the blood

• exercise intensity at which lactate starts accumulates in the blood
• Reduces energy production

• Increasing pCO2
• Increasing temperature
• Increasing 2,3DPG
• Increased acidity (dcreased pH)

Results in more unloading of oxygen in tissues

It is shunted from the gut and kidneys and perfused to the muscle

Cardiac output (CO)= (Heart rate [HR])(stroke volume [SV])

HR= (SA node rate + autonomic input)

SV=(venous X force of contraction)

INcreases via changes in HR and SV

• 100bpm
• Caused by a release of parasympathetic inhibition of the sinoatrial node

Sympathetic control

Mean arterial pressure (MAP)= (2/3)(Diastolic) +(1/3)(Systolic)

• total peripheral resistance (TPR) =
• (Mean arterial pressure)/
• (Cardiac output)

• Arteriovenous oxygen difference =
• (oxygen consumption)/
• (cardiac output)

• By increasing the force of contraction
• End-DIastolic volume (venous return)

• By skeletal and respiratory pumps
• Peripheral vasocontriction

• CO increases
• TPR decreases

• The motor cotext resets baroreceptor threshold
• Baroreceptor afferents are inhibited
• Muscle chemoreceptor (responding to metabolites) trigger CNS to override the baroreceptor

INcreasing cardiac output through effects on stroke volume

• Leads to a large left ventricle volume (increasing the venous return)
• Raise lactate threshold

raise lactate threshold

• Can increase HDL:LDL ratio
• Increase HDL
• Decreases LDL
• Lowering resting blood pressure
• Increase maximal oxygen uptake

• They can remove glucose from the blood more quickly and with much less insulin (=increased insulin sensitivity) than people who are sedentary
• Thus regular exercise can reduce your risk of developing type II diabetes