GLOSSARY

Hormonal Circadian Regulation coordinates hormonal signaling with biological time.

Circadian rhythms relate to biological clocks, while observed daily patterns also reflect sleep, food and activity. Sleep loss can alter appetite and food choice, but ghrelin and leptin do not change in the same direction in every study. Meal timing should fit training and intake needs. One timing experiment is not a universal rule to omit dinner or fast every athlete; total intake, schedule and individual tolerance still matter.

Synthesis, storage, secretion, transport and clearance are distinct processes. Blood concentration reflects entry and removal rather than directly measuring secretion; exercise-related plasma-volume changes can also affect it. Half-life depends on hormone form and method and is not identical to the duration of all effects. Comparisons therefore need sampling time, previous food and recent activity standardized or recorded rather than interpreting isolated concentration differences without context.

Cortisol supports fuel regulation, stress responses and other functions rather than simply destroying muscle. Secretion has rhythms and pulses; awakening, clock time, illness and exercise affect measurement. A temporary exercise rise is not equivalent to chronic hypercortisolism. The testosterone-to-cortisol ratio is not a standalone overtraining diagnosis either; symptoms, performance trends and standardized sampling conditions must accompany it rather than treating a transient value as proof of harmful catabolism.