IGF-1 LR3 for Bodybuilding

IGF-1 LR3 for Bodybuilding: Dosage, Side Effects, Dangers

Last updated on November 22nd, 2023 at 07:07 am

IGF-1 LR3, also known as Long R3 Insulin-like Growth Factor-1, is a powerful peptide hormone that has become popular among bodybuilders and athletes for its muscle-building and fat-burning effects. However, IGF-1 LR3 is also one of the most controversial bodybuilding drugs due to its potential side effects and legal status. If you’re considering the purchase of peptides like IGF-1 LR3, it’s crucial to thoroughly research their benefits and risks and make an informed decision.

This in-depth guide will cover everything you need to know about using IGF-1 LR3 for bodybuilding, including:

  • What is IGF-1 LR3 and how does it work?
  • Benefits of IGF-1 LR3 for muscle growth
  • Proper dosage and cycle length
  • How to inject and stack IGF-1 LR3
  • Side effects and safety concerns
  • Is IGF-1 LR3 legal? Laws and regulations
  • Alternative options to IGF-1 LR3

We’ll also compare IGF-1 LR3 to other popular performance-enhancing drugs like human growth hormone (HGH) to help you make an informed decision about whether IGF-1 LR3 is right for your bodybuilding goals.

What is IGF-1 LR3?

IGF-1 LR3 is a modified and more potent version of insulin-like growth factor-1 (IGF-1), which is a hormone produced primarily in the liver that plays a key role in childhood growth and continues to have anabolic, or muscle-building, effects in adults.

The IGF-1 produced in your body is regulated by growth hormone (GH) released by the pituitary gland. It’s actually GH that stimulates your liver to produce IGF-1 to promote muscle growth, which is why GH is often abused by athletes and bodybuilders.

IGF-1 LR3 has been synthetically altered to enhance its anabolic properties. The modification to the IGF-1 protein prevents it from being degraded by your body, which greatly extends its half-life and allows it to remain active in your tissues for up to 20-30 hours.

Regular IGF-1 has a half-life of less than 15 minutes, so very little ends up reaching your muscles. But IGF-1 LR3 is able to build up to much higher concentrations, providing consistently elevated IGF-1 levels for improved nutrient partitioning and protein synthesis.

IGF-1 LR3 for Bodybuilding

How IGF-1 LR3 Works for Muscle Growth

To understand how IGF-1 LR3 builds muscle, it helps to first understand the effects of normal IGF-1. The basics are:

  • Increased Protein Synthesis: IGF-1 stimulates muscle protein synthesis and inhibits protein breakdown, leading to an overall increase in muscle protein content.
  • Nutrient Uptake: IGF-1 makes your cells more sensitive to insulin’s effects on nutrient uptake. So your muscles can absorb more amino acids, glucose, and other nutrients needed for growth.
  • Muscle Cell Differentiation: IGF-1 causes immature muscle cells to differentiate into mature muscle cells that are capable of fusion and growth.
  • Anti-Catabolic Effects: IGF-1 counteracts muscle-wasting hormones like cortisol to reduce muscle protein breakdown.
  • Boosts Growth Hormone: IGF-1 increases GH receptors on your cell surfaces. This makes your tissues more responsive to the GH you produce.

When you buy IGF-1 LR3, you’re investing in a powerful tool for amplifying all of these muscle-building processes. By sustaining higher IGF-1 concentrations for longer periods, IGF-1 LR3 magnifies all of these muscle-building processes. The constant flood of IGF-1 in your muscles boosts protein synthesis 24/7, reduces catabolism, enhances nutrient delivery, and primes your cells for growth.

IGF-1 LR3 also increases the uptake of other amino acids and sugars which further boosts muscle growth. It’s particularly effective when combined with growth hormone.

Many bodybuilders use IGF-1 LR3 to break through plateaus and maximize their genetic potential when natural growth hormone production starts to decline.

Benefits of IGF-1 LR3 for Bodybuilding

Here are some of the major benefits that make IGF-1 LR3 so popular for building muscle mass:

1. Dramatic Muscle Growth

Numerous studies have found that IGF-1 LR3 can rapidly increase lean body mass and muscle cross-sectional area. Anecdotal evidence from bodybuilders suggests gains of 10-15 pounds in 6-12 weeks are possible with proper IGF-1 LR3 dosing.

The rapid muscle-building effects of IGF-1 LR3 come mainly from the amplification of protein synthesis and nitrogen retention. However, the enhanced nutrient shuttling also provides muscles with the raw materials needed for accelerated growth.

Users often report their muscles feeling pumped 24/7. Even resting muscle appears fuller. The intense muscle-building effects are maximized when combining IGF-1 LR3 with weight training.

2. Fat Loss

IGF-1 LR3 also offers powerful fat loss benefits. By increasing your body’s sensitivity to insulin, IGF-1 LR3 promotes better nutrient partitioning so more calories are shuttled towards muscle growth rather than fat storage.

The peptide puts your body in an anabolic state so that the meals you eat are more likely to be stored as glycogen in muscle tissue rather than body fat. IGF-1 LR3 stacks well with growth hormone (GH) and anabolic steroids for further body recomposition benefits.

3. Enhanced Recovery

Many athletes, not just bodybuilders, use IGF-1 LR3 because the boosted protein synthesis enhances muscle repair. IGF-1 LR3 speeds up recovery between workouts so you can hit it hard more frequently.

Users also report accelerated recovery from sports injuries when applying IGF-1 LR3 locally to the injured site. General soreness is reduced allowing you to smash through plateaus.

4. Improved Collagen Synthesis

IGF-1 is one of the key regulators of collagen synthesis. Increasing IGF-1 via administration of IGF-1 LR3 has been shown to attenuate age-related declines in collagen production. This results in benefits like improved skin elasticity, faster wound healing, and joint support.

5. Long-lasting Effects

A major advantage of IGF-1 LR3 over natural IGF-1 is its extended half-life of 20-30 hours. This means far fewer injections are needed compared to growth hormone or insulin. IGF-1 LR3 is typically injected every day or every other day.

The lengthy half-life provides a consistent flow of IGF-1 to your muscles. This leads to steady muscle building rather than spikes and crashes.

IGF-1 LR3 for Bodybuilding

Proper IGF-1 LR3 Dosage & Cycle

Since IGF-1 LR3 is not approved for human use, there are no official guidelines for therapeutic dosing. Bodybuilders have experimented over the years to find optimal IGF-1 LR3 doses for muscle growth and fat loss.


The most common IGF-1 LR3 dosage ranges from 40-80 mcg per day. While its anabolic effects have been shown in studies using doses around 20-30 mcg, most bodybuilders report preferring 50-100 mcg for the best muscle-building results.

IGF-1 LR3 doses above 100 mcg per day often don’t provide additional benefits, but will increase the risk of side effects. Because IGF-1 LR3 has systemic effects, it’s considered less dose-dependent than SARMs or steroids.

Start at the low end of the dosage range and assess your tolerance and results before increasing the dose. Never take more than 100 mcg daily.

Since IGF-1 LR3 has a half-life of around 20-30 hours, it only needs to be injected once or twice per day. Most users inject their full daily IGF-1 LR3 dose all at once either in the morning or post-workout. But you can also split the dose into two smaller injections.

Women are often more sensitive to the effects of IGF-1 LR3 and may want to stay on the lower end of the dosage range.

Cycle Length

Common IGF-1 LR3 cycles range from 4-12 weeks. Short cycles of 4-6 weeks are recommended for beginners to assess tolerance. More advanced users might do 8-12 week cycles to maximize muscle building.

Longer IGF-1 LR3 cycles increase the risks of developing insulin resistance and other side effects. It’s best to keep cycles under 12 weeks even when using breaks in between. Most users report the benefits taper off after 8-10 weeks anyway.

IGF-1 LR3 is almost always cycled rather than used as a constant base. Time off between cycles allows your body’s natural IGF-1 production to return to normal. This minimizes desensitization and ensures future cycles remain effective.

Time on + PCT = Time off is a good rule of thumb. So run an 8-week cycle, follow it with 4 weeks PCT, and then take at least another 8 weeks off before cycling again.

How to Inject IGF-1 LR3

Because of its poor oral bioavailability, IGF-1 LR3 must be injected subcutaneously or intramuscularly. Here are some guidelines for properly injecting IGF-1 LR3:

  • Use an insulin syringe for precise measurement and easy subQ injections. A 0.5 mL or 1 mL syringe with a 29-31 gauge, 1/2 inch needle is recommended.
  • Injection sites include the abdominal area, obliques, thighs, hips, rear delts or biceps. Rotate sites to avoid lumps.
  • Reconstitute the IGF-1 LR3 powder with sterile water or bacteriostatic water. 2 mL per vial is common.
  • Inject shortly after mixing. Store reconstituted IGF-1 LR3 vials refrigerated if needed for a few weeks.
  • SubQ injections only require inserting the needle into the fat under your skin at a 45 degree angle. No need to go into muscle.
  • Apply pressure after withdrawing the syringe to avoid leakage. Gentle massage helps disperse the fluid.
  • Never share needles or vials. Use a clean needle and sterile technique for each injection.

IGF-1 LR3 can be injected on its own or in combination with other compounds like growth hormone or anabolic steroids.

Stacking IGF-1 LR3 For Best Results

Due to its synergistic effects, IGF-1 LR3 stacks very well with other growth hormones and anabolic steroids. Some effective stacks include:

  • IGF-1 LR3 & Growth Hormone – Growth hormone increases IGF-1 receptors to amplify results. 5 IU per day is a common GH dose.
  • IGF-1 LR3 & Testosterone – Testosterone boosts protein synthesis and androgen receptors for greater muscle growth.
  • IGF-1 LR3, GH & Test – This trio is one of the most potent anabolic stacks, boosting muscle growth on multiple fronts. But it also increases side effects.
  • IGF-1 LR3 & Trenbolone – The powerful bulking and nutrient repartitioning effects of trenbolone combine well with IGF-1 LR3’s muscle-building properties.
  • IGF-1 LR3 & Anavar – Anavar has direct anabolic effects and increases IGF-1 production for further growth promotion. Especially useful during cutting cycles.

When stacking multiple compounds, it’s best to start on the lower side of the dosage range for each to assess tolerance and potency. More advanced users might try running two compounds at standard dosage ranges.

Side Effects of IGF-1 LR3

Despite its impressive ability to build muscle, IGF-1 LR3 is not without side effects. Some users report no negative reactions, while others experience more pronounced side effects. Here are some of the most common:


Supraphysiological levels of IGF-1 LR3 can make you more sensitive to insulin, increasing the risk of low blood sugar when you go too long without eating carbohydrates. Symptoms like dizziness, sweating, trembling, and blurred vision are signs of hypoglycemia.

Having a carbohydrate source on hand at all times can counteract this side effect. Reducing your IGF-1 LR3 dosage often minimizes the risk of hypoglycemia.

Numb Hands

Tingling or numbness in your fingers or hands is another fairly common side effect of IGF-1 LR3. It’s referred to as carpal tunnel syndrome and results from fluid retention compressing the median nerve.

The numb hands usually subside shortly after ending the IGF-1 LR3 cycle. But for some, it may persist longer term. Lower doses under 50 mcg per day reduce instances of numb hands.

Water Retention

Due to its pro-anabolic effects and ability to increase insulin sensitivity, IGF-1 LR3 can cause noticeable water weight gain. This is from increased intramuscular water storage, but can make your muscles look smoother and less defined.

Using low doses of an aromatase inhibitor or diuretic may help counteract the fluid retention. But avoiding rapid weight gain and maintaining a lean diet is more effective.

Joint & Back Pain

Some IGF-1 LR3 users report experiencing aches and pains in their joints, lower back, knees, wrists or elbows. This seems most common when using higher doses of IGF-1 LR3 for longer cycles.

It may be caused by the rapid weight gain putting more pressure on your joints and connective tissues. Reducing your dosage or shortening cycle length usually alleviates this side effect.


Supraphysiological levels of IGF-1 LR3 can make you more sensitive to insulin, increasing the risk of low blood sugar when you go too long without eating carbohydrates. Symptoms like dizziness, sweating, trembling, and blurred vision are signs of hypoglycemia.

Having a carbohydrate source on hand at all times can counteract this side effect. Reducing your IGF-1 LR3 dosage often minimizes the risk of hypoglycemia.

Increased Cancer Risk

One of the biggest concerns with IGF-1 LR3 is its potential to increase cancer risk. IGF-1 is known to play a role in tumor growth. Extended use could potentially promote cancer formation.

However, the cancer risk is considered low with short-term use of IGF-1 LR3. There’s no research showing cycles of 1-3 months increase cancer risk. But extended use without cycling off for long periods may be unwise.

Insulin Resistance

Since IGF-1 LR3 boosts insulin sensitivity during use, this effect can eventually trigger insulin resistance. Longer cycles without breaks can desensitize cells to insulin’s effects.

Symptoms like lethargy, brain fog, disrupted sleep, and sugar cravings may indicate the onset of insulin resistance. Cycling IGF-1 LR3 rather than continuous use reduces this risk.

IGF-1 LR3 for Bodybuilding

Is IGF-1 LR3 Legal?

In most countries, including the United States, IGF-1 LR3 is a prescription-only drug. But it’s not approved for medical use anywhere in the world. IGF-1 LR3 is only available through underground labs and black market suppliers.

Purchasing, using, and possessing IGF-1 LR3 can potentially result in criminal penalties. But it rarely attracts law enforcement attention since it’s not as well known as steroids or growth hormones.

There’s no drug testing for IGF-1 LR3 usage in professional, college, or Olympic sports. IGF-1 LR3 cycles are essentially undetectable since it’s an analog of the body’s innate IGF-1 hormone.

So while not explicitly illegal in most places, the legal status of IGF-1 LR3 is a very gray area. Use at your own discretion based on your location.

Health Risks & Dangers of IGF-1 LR3

Despite being promoted for bodybuilding purposes, IGF-1 LR3 has never been properly studied for long-term safety in humans.

Research doses are typically 20-40 mcg, while bodybuilders often take 80-100 mcg for months at a time. This supraphysiological dosing likely amplifies the health risks.

Here are some of the most serious potential dangers of using performance-enhancing doses of IGF-1 LR3:

  • Cancer Growth – IGF-1 is known to play a role in tumor development and the spread of cancers. Extended IGF-1 LR3 use could increase risks.
  • Organ Enlargement – Excessive doses of IGF-1 LR3 may cause abnormal growth in organs like your heart, kidneys and prostate. This is referred to as acromegaly.
  • CellMutation – Some researchers believe IGF-1 may cause DNA damage and cell mutations that could result in cancerous changes. More human research is still needed.
  • Insulin Resistance – High IGF-1 levels make cells less sensitive to insulin over time, resulting in diabetes-like effects.
  • Hypoglycemia – IGF-1 LR3 can induce episodes of dangerously low blood sugar, especially when used alongside insulin or oral diabetes drugs.

Make sure you get periodic health checkups and screenings if you use IGF-1 LR3 regularly. And limit cycles to 6-8 weeks to be on the safer side.

Natural Alternatives to IGF-1 LR3

Given the legal issues and health risks of IGF-1 LR3, you may want to consider some natural alternatives instead:

  • Creatine – One of the most studied sports supplements. Creatine enhances strength, power, muscle growth, and recovery without side effects for most people.
  • Branched Chain Amino Acids (BCAAs) – Essential amino acids like leucine directly stimulate muscle protein synthesis and slow protein breakdown.
  • HMB – HMB is a metabolite of the amino acid leucine that has been shown to increase muscle mass and strength in clinical studies.
  • Beta-hydroxy beta-methylbutyrate (HMB) – A metabolite of the amino acid leucine that has been shown to slow muscle protein breakdown and increase muscle mass and strength.
  • Whey Protein – A high-quality source of protein and amino acids ideal for supporting muscle growth when combined with training.
  • Citrulline – This amino acid boosts nitric oxide levels to enhance muscle pumps, endurance, and recovery. Citrulline also raises growth hormone levels.
  • Prohormones – Compounds that convert into active androgens and promote muscle growth. But prohormones come with side effects and are banned in sport.
  • Intense Training – Progressive strength training provides a natural stimulus for increased IGF-1 and growth hormone production.

You can maximize your natural IGF-1 production through proper resistance training, nutrition, sleep, and stress management. While the results may not be as dramatic as IGF-1 LR3, a natural approach is sustainable long-term.

IGF-1 LR3 vs. Growth Hormone

Growth hormone (GH) is probably the most comparable injectable peptide hormone to IGF-1 LR3 in terms of muscle building effects.

IGF-1 is actually stimulated by your body’s natural GH production. Both compounds boost protein synthesis, enhance recovery, reduce catabolism, and enable muscle gains.

However, there are some key differences between the two that are worth highlighting:

  • Strength Gains – GH promotes more significant increases in functional strength compared to IGF-1 LR3. IGF-1 LR3 is stronger for stimulating size/hypertrophy specifically.
  • Fat Loss – Growth hormone tends to be more effective than IGF-1 LR3 for targeted fat loss, especially visceral fat in the abdomen. GH speeds up lipolysis.
  • Half-Life – IGF-1 LR3 lasts much longer, with an active half-life of around 20-30 hours compared to just a few hours with growth hormone. Less frequent injections are needed.
  • Side Effects – The most common side effect issues seen with GH like water retention, joint pain, and insulin resistance tend to be lower with IGF-1 LR3.
  • Cancer Risk – IGF-1 administration likely elevates cancer risk more than growth hormone. But both can potentially promote tumor growth when used long-term.

For the best of both worlds, many bodybuilders stack IGF-1 LR3 with low doses of growth hormone (2-5 IU daily). This provides complementary benefits while mitigating the side effects of high GH dosing.

Is IGF-1 LR3 Worth Trying?

If you are an experienced bodybuilder looking to push your genetic limits, IGF-1 LR3 offers intriguing muscle-building properties unmatched by natural supplements. But it is one of the most potent SARMS and comes with more unknown risks.

Approach IGF-1 LR3 cautiously, start with conservative dosing, monitor health markers, and keep cycles short. And weigh whether the minimal extra gains are worth the potential side effects.

For most trainees focused on sustainable fitness, legal supplements provide sufficient support without jeopardizing your health. But at the end of the day, you must decide if IGF-1 LR3’s benefits outweigh the risks based on your bodybuilding objectives.


IGF-1 LR3 is considered one of the most anabolic compounds for rapid lean mass gains. But with its power comes additional side effects.

This guide covers everything you need to know about utilizing IGF-1 LR3 safely and effectively. While results can be significant, cycling-off periods are crucial to avoid desensitization.

Always start low with dosing and cycle length until you know how your body responds. And monitor for any warning signs like hypoglycemia, fluid retention, or joint pain.

With disciplined use, IGF-1 LR3 can help advanced weightlifters and physique competitors break through plateaus and reach new levels of muscular development. But natural muscle-building options may be the smarter choice for most.

Leave a Reply

Your email address will not be published. Required fields are marked *