S4 Andarine

What is S4 (Andarine)

S4, also known as Andarine, is a selective androgen receptor modulator (SARM) being studied for its anabolic effects on muscle growth and fat loss. Originally developed for treating muscle wasting and osteoporosis, S4 is now widely used in research involving body recomposition. It binds selectively to androgen receptors in muscle and bone, making it a popular compound among bodybuilders and athletes seeking lean gains, improved vascularity, and enhanced definition without the water retention common with anabolic steroids.

Benefits of S4 (Andarine)

• Promotes lean muscle preservation and fat loss
• Improves vascularity, muscle hardness, and definition
• Enhances strength and endurance during training
• Supports muscle retention during cutting phases
• Does not convert to estrogen or cause water retention  

How to Use S4 (Andarine)

Previous Research Dosages Used: Common research protocols explore dosages of 25mg to 50mg daily, often divided into two doses due to its short half-life. Studies run for 6–8 weeks, focusing on muscle retention, strength output, and fat reduction. Some trials implement 5-days-on / 2-days-off schedules to mitigate vision-related side effects.

Frequently Asked Questions

1. Does S4 cause vision issues?  
Yes, some users in studies report mild visual side effects such as a yellow tint or difficulty adjusting to darkness. These effects are usually temporary and dose-dependent.

2. Can S4 be used during a bulking phase?  
While S4 is best known for cutting and recomposition, it can support lean bulking when paired with proper diet and training due to its anabolic effects.

3. Is post-cycle therapy (PCT) needed after S4?  
S4 may cause mild testosterone suppression. Many research protocols suggest a short PCT after an 8-week cycle to restore hormonal balance.

4. How quickly do results from S4 appear?  
Researchers note early changes in vascularity and muscle tone within 2–3 weeks, with more noticeable fat loss and definition improvements by week 4–6.

5. Can S4 be stacked with other SARMs?  
Yes, S4 is commonly stacked with SARMs like Ostarine (MK-2866) or Cardarine (GW-501516) for synergistic effects in cutting or recomposition protocols.