Source comparison
Dosing Protocols: Single vs Multiple Daily Injections
Most research protocols fall into one of three categories: single daily injection (100–200mcg before sleep), twice-daily injection (100–200mcg pre-workout and pre-sleep), or three-times-daily injection (100–200mcg upon waking, pre-workout, and pre-sleep). The
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- Most research protocols fall into one of three categories: single daily injection (100–200mcg before sleep), twice-daily injection (100–200mcg pre-workout and pre-sleep), or three-times-daily injection (100–200mcg upon waking, pre-workout, and pre-sleep). The total daily dose ranges from 100mcg at the conservative end to 600mcg at the upper research boundary, but dose escalation doesn't scale linearly with GH output. Frequency matters more than total quantity.
- Single daily dosing at 100–200mcg is the minimalist approach, typically timed 30–60 minutes before sleep to coincide with the nocturnal GH pulse window. The body naturally releases the largest GH pulse of the day during slow-wave sleep (stages 3–4), and pre-sleep GHRH administration amplifies this endogenous surge. A study in The Journal of Clinical Investigation found that pre-sleep GHRH analogue injection increased nocturnal GH secretion by 3.2-fold compared to placebo without affecting daytime GH patterns. This protocol works well for researchers prioritising recovery and lipolysis over acute anabolic signalling.
- Twice-daily protocols split the dose into two 100–200mcg injections: one pre-workout (60–90 minutes before training) and one pre-sleep. This approach captures both the exercise-induced GH pulse and the nocturnal pulse, extending the anabolic window across the day. Pre-workout GH elevation enhances lipolysis during training and increases post-exercise IGF-1 synthesis in skeletal muscle. Research from the European Journal of Applied Physiology showed that GHRH administration 90 minutes before resistance training increased post-workout serum IGF-1 by 28% compared to training alone, suggesting enhanced anabolic signalling in muscle tissue.
- Three-times-daily protocols. Typically 100–200mcg upon waking, pre-workout, and pre-sleep. Represent the upper range of research dosing. Morning administration targets the smaller post-awakening GH pulse, midday or pre-workout dosing aligns with training windows, and evening dosing amplifies nocturnal secretion. Total daily doses in this range (300–600mcg) approach the threshold where receptor desensitisation becomes a concern: continuously elevated GHRH receptor occupancy can downregulate receptor density over weeks, blunting GH response. This is why we recommend cycling protocols rather than continuous administration beyond 12–16 weeks.