Cortisol
Hormone Stress response Energy balance
Cortisol is a glucocorticoid hormone. It rises with context, is naturally higher in the morning, and supports energy provision, load tolerance and recovery. In massing, cortisol acts as a signal within the system of training, energy availability, sleep and stress control—not a “gains killer” per se.
Note
Term and System Context
Short take Cortisol is produced in the adrenal cortex, follows a circadian rhythm (higher in the morning, lower at night) and responds in pulses to stressors—including training. It mobilizes energy, modulates inflammation and influences recovery. Always interpret it in system with Testosterone and Growth hormone, steered by training quality and sufficient energy intake.
- Signal, not an enemy: Acute rises are normal and sometimes necessary. The issue is chronic, context-free stress during a deficit.
- Hardgainer trap: High NEAT + low calories + high volume = fatigue up, massing flat.
- System over single value: Progress comes from training within MEV–MRV, guided by RIR/RPE and stable sleep.
Measurement and Operationalization
Single readings without context mislead. Patterns, time of day and symptoms are more informative.
- Diurnal curve: Higher in the morning, lower at night. Always record the sampling time.
- Load & sleep: Hard sessions, sleep loss and prolonged diet stress can transiently raise cortisol—this is a steering signal, not a verdict.
- Training effect: Acute post-training peaks are normal; long-term, the SRA cycle with adequate recovery is what matters.
Guardrails for Massing
- Sleep: 7–9 hours consistently. Sleep stabilizes daytime energy and training quality—see Myth #6.
- Energy availability: Avoid chronic deficit while massing. Let Rate of Gain guide fine-tuning.
- Volume & deloads: Keep volume within MEV–MRV; deload when fatigue flags rise.
- Timing & carbs: Carbohydrates around training can ease load processing.
- Partner hormones: Consider context with Testosterone & Growth hormone.
Practice – 14-Day Orientation
- Day 0: Set the base: protein, calorie corridor, stable sleep window, clear plan (loads, reps).
- Daily: Morning bodyweight, sleep duration/quality, steps (NEAT), log training with RIR. Use weekly averages.
- Day 14: If fatigue ↑ or RoG ↓, co-adjust volume, NEAT and energy (deload if needed; raise around-training carbs).
Hardgainer Calorie Calculator
- BMR → TDEE: Mifflin–St. Jeor × activity factor
- HG Boost: +0–15% for high NEAT/TEF
- Targets: Maintenance, Lean Bulk (+10%), Aggressive (+20%)
- Macros (g/kg): Adjustable protein and fat
- Carbs: Auto from remaining kcal
- Meal split: 3–6× per day (P/F/C per meal)
- HUD/Dashboard: Target kcal, intensity, pie stack
- Hydration target: roughly 35 ml per kg bodyweight
- Guides: Pro tips & glossary links
Common Misconceptions
- “Cortisol is always bad.” No—it’s a regulatory signal. Dose, duration and context (sleep, calories, volume) decide the effect.
- “Cardio kills gains because of cortisol.” Dose and timing matter. With systemic control (energy, recovery), conditioning complements lifting—see Myth #3 and SRA.
- “One high value = chronic stress.” Single numbers without time/context say little. Use trends and symptoms—see the series.
- “Supplement X lowers cortisol and fixes everything.” Foundations first: protein, creatine, sleep, volume control—see Myth #10.
Studies and Evidence (PubMed)
If you want to dive deeper into the science of cortisol, here is a small selection of studies on PubMed:
- Circadian rhythmicity of cortisol and body temperature – Chronobiology International, 2001
- Resistance exercise order and hormonal responses (including cortisol) in normal-weight and obese men – Asian Journal of Sports Medicine, 2016
Note: These papers are written for professionals. They do not replace personal medical advice.
“Five to six hours of sleep are enough for muscle growth”
Too narrow. Sleep drives recovery, training quality and daytime energy. A stable sleep window often beats short-term product promises. Details in Myth #6.