Timing of HGH - tricky question

Research on timing of GH use in healthy, resistance-trained people (like bodybuilders) is very limited compared to studies in GH-deficient patients. Here’s what we know:

1. Natural physiology (how the body does it)

In healthy adults, the biggest GH surge happens shortly after sleep begins (deep slow-wave sleep).

Smaller pulses occur during the day, often linked to fasting or exercise.This suggests that the body is primed to use GH at night for tissue repair, fat mobilization, and recovery.

2. Studies in GH-deficient patients

In GH-deficient people, evening injections better mimic normal patterns and restore more natural hormone–metabolite relationships.

Morning injections disrupt circadian patterns, cause higher daytime insulin, and blunt some metabolic benefits.→ So, nighttime GH dosing comes closest to “natural” release.

3. Bodybuilder-focused studies

In healthy, trained men, short-term GH administration (morning vs. night) hasn’t shown a clear muscle-building benefit.

Most increases in “lean mass” are actually water retention rather than true muscle hypertrophy.GH does help with fat burning (higher fat oxidation, lower fat mass) and tissue recovery (collagen synthesis), but direct muscle growth is minimal unless combined with anabolic steroids (e.g., testosterone).

4. Practical timing strategies bodybuilders use (based on theory, not proof)

Before bed → to mimic the natural nighttime GH pulse, supporting recovery.

Pre-fast or morning fasted state → to maximize fat burning, since GH shifts metabolism toward fat use when insulin is low.Post-workout → sometimes used to pair with exercise-induced GH pulses, though data supporting this for hypertrophy is weak.

⚠️ Bottom Line

For pure muscle growth: GH timing doesn’t seem to matter much — GH alone isn’t a strong muscle builder in healthy bodybuilders.

For fat loss & recovery: Nighttime (before bed) dosing best mimics natural physiology and may support recovery. Morning (fasted) dosing is often used for fat-burning goals.For synergy with steroids: When combined with anabolic agents, timing is less critical — the combined effect is what drives size gains.