MK-677, also known as Ibutamoren or Nutrabol, is a compound that has gained significant attention for its ability to increase levels of growth hormone (GH) and insulin-like growth factor 1 (IGF-1). It is a non-peptidic, orally active, and selective agonist of the ghrelin receptor. This means it can be taken as a pill and works by mimicking the action of the hormone ghrelin, which regulates appetite and energy use in the body. Unlike anabolic-androgenic steroids (AAS), MK-677 is non-hormonal and does not suppress the body's natural hormone production, meaning it does not require a post-cycle therapy (PCT).
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How MK-677 Works and Its Benefits
MK-677 functions as a growth hormone secretagogue, which means it signals the pituitary gland to increase the secretion of growth hormone. This, in turn, leads to a cascade effect, significantly raising circulating levels of IGF-1. A key advantage of MK-677 is that it achieves this without increasing cortisol levels, a stress hormone that can have catabolic effects.
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Human studies have demonstrated several notable benefits of MK-677:
Increased Muscle Mass: Research has shown it to be effective in increasing lean body mass.
Enhanced Bone Mineral Density: By raising GH and IGF-1 levels, it can contribute to stronger bones.
Significant IGF-1 Increase: A daily dose of 25mg has been shown to increase IGF-1 levels by 60% in just six weeks, with increases up to 72% after 12 months of consistent use.
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Dosage, Cycle Length, and Side Effects
The recommended dosage for MK-677 is typically 25mg daily. Due to its long half-life of around 24 hours, a single daily dose is sufficient. The compound is best utilized over a long cycle of at least three months, with some users increasing the dosage each month for greater effect. The optimal time to take MK-677 is at night, just before bed. This is because GH secretion is naturally at its highest during sleep, and the compound can promote deeper, more restful sleep.
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A common side effect that users may notice almost immediately is numb or tingly hands upon waking. This is a normal and expected side effect of the increased GH levels in the body and should not be a cause for concern.
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Other potential side effects include:
Increased Hunger: As MK-677 mimics ghrelin, it can significantly increase appetite.
Lethargy: Some users may experience fatigue or lethargy, which is why taking it at night is a popular choice.
Impaired Insulin Sensitivity: MK-677 can lead to a slight decrease in insulin sensitivity, which is a key consideration for long-term use.
Water Retention: Users may experience some water retention, which contributes to the increased body weight and fullness.