What Is Growth Hormone and Why Is It Important?
Growth hormone (GH, somatotropin) is one of the most important anabolic hormones in the body. It is produced by the pituitary gland, and its main functions include muscle growth, fat burning, maintaining bone density, skin regeneration, and strengthening the immune system. The greatest GH secretion occurs precisely during sleep!
📊 Sleep Stages and Growth Hormone Secretion
| Sleep stage | GH secretion | Duration per night | Importance for recovery |
|---|---|---|---|
| Light sleep (NREM 1-2) | Low | ~50% of sleep | Transitional stage |
| Deep sleep (NREM 3, SWS) | VERY HIGH — up to 70% of daily GH | ~20-25% of sleep | Critical for muscle recovery |
| REM Sleep | Medium | ~20-25% of sleep | Brain recovery, memory |
Key takeaway: Deep sleep (SWS — slow-wave sleep) is the golden hour for growth hormone. The first 2-3 hours of sleep, when deep sleep dominates, are critical — that is when the largest amount of GH is released throughout the night.
🌙 How to Optimize Sleep for Greater GH Release
⏰ Go to bed by 23:00
Deep sleep phases dominate in the first half of the night. The earlier you fall asleep, the more deep sleep you get. The ideal time to go to bed is 21:30-22:30.
🍽️ Do Not Eat Before Bed
The last meal should be 2-3 hours before sleep. Insulin released after a meal suppresses growth hormone secretion. Especially avoid carbohydrates before bed.
🌡️ Cool Bedroom Temperature
The optimal temperature for GH secretion is 18-20°C. An environment that is too warm interferes with deep sleep and reduces GH release.
📵 Darkness and Avoiding Screens
Blue light from screens suppresses melatonin production, which also indirectly affects GH secretion. 1 hour before sleep — no screens.
🏋️ Training and Growth Hormone
Physical exercise is the second most important natural GH stimulator (after sleep). Here are the most effective types of training:
- High-intensity training: HIIT (15-20 min.) can increase GH after training. The effect lasts 1-2 hours after exercise.
- Strength training with short rest periods: 6-10 reps, 3-4 sets, 60-90 sec. rest between sets. Multi-joint exercises (squats, deadlift) stimulate more GH.
- Evening workouts: Training at 16-18 h aligns best with the natural rhythm of GH secretion. After evening training, the GH response is stronger during sleep.
💊 Supplements for Growth Hormone Secretion
| Supplement | Dose before sleep | Mechanism of Action |
|---|---|---|
| Melatonin | 0.5-1 mg | Improves sleep quality, indirectly increases GH secretion |
| Glycine | 3-5 g | Reduces body temperature, improves deep sleep, may increase GH |
| Arginine | 5-10 g (on an empty stomach) | Suppresses the release of somatostatin (GH inhibitor) |
| GABA | 500-1000 mg | Calms the nervous system, may increase GH (research data limited) |
| Mucuna Pruriens | 300-500 mg (L-dopa equivalent) | Natural dopamine precursor, stimulates growth hormone-releasing hormone (GHRH) |
🛒 Recommended Sleep and GH Products
📈 Daily Rhythm of Growth Hormone Secretion
GH secretion occurs in pulses — every 3-5 hours the pituitary gland releases a wave of GH. The largest wave (up to 70% of daily GH) occurs in the first hours of sleep. After that — smaller waves during the day, especially after workouts and on an empty stomach.
- 22:00-02:00: Largest GH wave — deep sleep
- 04:00-06:00: Second wave — during REM sleep
- After the workout: 200-400% increase for 1-2 hours
- Fasting (12+ hours): GH levels can increase up to 2 — fasting is a powerful GH stimulator
❓ Frequently Asked Questions
Can growth hormone be increased naturally without injections?
Yes! Sleep, high-intensity training, intermittent fasting (intermittent fasting), and certain supplements (arginine, glycine, melatonin) can naturally increase GH secretion. The effect is not as dramatic as synthetic GH, but it is safe and sustainable.
When is the best time to measure growth hormone?
GH secretion is pulsatile, so a single blood test is often uninformative. It is better to measure IGF-1 (insulin-like growth factor-1) — it reflects the average GH level over the past 24 hours and is more stable.
Are carbohydrates before bed really bad?
Yes, especially simple carbohydrates. They cause an insulin spike, and insulin inhibits GH secretion. If you want to eat before bed, choose protein with a small amount of fat (e.g., a casein shake).