When exercise decreases in intensity

When exercise is performed under a glycogen depleted state

During prolonged exercise at a constant intensity

When exercise is performed after high fat loading diet

When exercise intensity increases 

Inhibits myosin ATPase activity and increase extracellular potassium [K⁺]

Increases in calcium phosphate and inhibiting myosin ATPase activity

increase in extracellular K⁺ and increases in calcium phosphate

Blocking Ca²⁺ binding to troponin C and combining Ca²⁺ with Pi

Decreases Ca²⁺ availability from the sarcoplasmic reticulum and blocks Ca²⁺ binding troponin C

Failure of muscles to respond to an electrical impulse and produce force

Failure of the muscle contractile apparatus (myosin & actin) to function and produce force

Inability of a muscle to complete a task

Any exercise-induced reduction in force generating capacity, reversible by rest

Failure of the CNS to maintain electrical activation of muscle motor units

~70%

~25%

~90%

~60%

~40%

25% and 35%

10% and 50%

40% and 20%

30% and 30%

20% and 40%

Calcium availability is increased after the sarcoplasmic reticulum receives stimulus from an action potential

Calcium [Ca++] concentration is lower in the sarcoplasmic reticulum, resulting in decreased Ca++ availability and therefore binding to troponin C

Calcium phosphate is degraded releasing calcium into the sarcoplasmic reticulum inhibiting contraction of myosin and actin

Calcium causes pH to decrease resulting in insufficient buffer availability 

Calcium is blocked from combining with tropomyosin and contractions are inhibited

Convective and conductive zones

Conductive and respiratory zones

Conducive and respiratory zones

Convective and respiratory

Bronchioles and alveoli 

K⁺ and HPO₄2-

Cl^- and Na⁺

HPO₄^2- and Na+

Ca²⁺ and HCO₃^-

Na⁺ and K⁺

Cell proteins

Kidney buffering

Bicarbonate-Carbonic acid buffering

Cellular buffering

Respiratory compensation

Facilitated diffusion

Active diffusion

Diffusion 

Active transport

Osmosis