Hormones
Cortisol, Total
What This Marker Tells Us
Measures the primary stress hormone your adrenal glands produce, which regulates metabolism, immune function, blood pressure, and your body's response to physical and psychological stress throughout the day
Why It Matters
Essential for survival, helping you respond to stress, maintain blood sugar between meals, regulate inflammation, and support circadian rhythm. Healthy cortisol follows a diurnal pattern: high in the morning to help you wake and face the day, then gradually declining toward evening. However, chronic stress, poor sleep, or illness can disrupt this pattern. Low cortisol may indicate adrenal insufficiency, chronic stress burnout, or HPA axis dysfunction, causing fatigue, low blood pressure, poor stress tolerance, and immune vulnerability. High cortisol suggests acute stress, Cushing's syndrome, or chronic activation of stress responses, promoting weight gain (especially abdominal), blood sugar dysregulation, bone loss, immune suppression, and mood disturbances. A single morning cortisol provides limited information since optimal levels vary by time of day and individual stress state.
How to Interpret Your Trends
Morning cortisol typically ranges from 10-20 μg/dL, supporting healthy wake-up and energy. Lower morning values (below 10 μg/dL) may indicate inadequate adrenal response, chronic stress, or poor sleep recovery. Higher values (above 20 μg/dL) might reflect acute stress, anxiety, or excessive stimulation. However, interpreting cortisol requires understanding timing; a single morning measurement misses the full diurnal pattern. Ideally, cortisol should be highest upon waking, then decline throughout the day. Consistently low or high readings, especially with symptoms, warrant deeper investigation including 4-point salivary cortisol testing to assess the complete rhythm.
What Influences This Marker
Cortisol rises with psychological stress, intense exercise, inadequate sleep, fasting, illness, inflammation, caffeine intake, and certain medications. Chronic stress can eventually lead to blunted cortisol responses. Cortisol decreases with effective stress management, adequate sleep, meditation, adaptogenic herbs, balanced nutrition, and appropriate recovery between workouts. Blood draw anxiety can elevate results. Cushing's syndrome, pituitary tumors, and chronic steroid use cause persistent elevation, while Addison's disease causes deficiency.
How Your Team Uses It
Your coach implements stress reduction techniques, recovery-focused training periodization that doesn't overwhelm your system, sleep hygiene protocols, and nutrition timing strategies to support healthy cortisol patterns throughout the day.
Related Signals We Also Review
DHEA-S, thyroid panel (TSH, free T4), fasting glucose, blood pressure, and symptoms to assess overall HPA axis and stress response function.