Ostarine and Cardarine Stack: What to Expect

Ostarine is a selective androgen receptor modulator (SARM), and Cardarine is a peroxisome proliferator-activated receptor delta (PPARD) agonist. Both substances are utilized by weightlifters to stimulate anabolism and lipolysis.

For men, an Ostarine and Cardarine stack is commonly administered during a cutting phase, with Ostarine producing mild increases in muscle hypertrophy, up to 10 pounds.

Women may also use this stack to enhance fat reduction. However, Ostarine is an effective muscle builder for females, with novices often adding up to 20 pounds of fat-free mass from a cycle.

Ostarine and Cardarine Stack

For Men

Moderate Cycle:

• Weeks 1–8: Ostarine 15 mg/day, Cardarine 10 mg/day

Aggressive Cycle:

• Weeks 1–8: Ostarine 20 mg/day, Cardarine 20 mg/day
• Weeks 9–12: Cardarine 20 mg/day

For Women

Moderate Cycle:

• Weeks 1–8: Ostarine 10 mg/day, Cardarine 10 mg/day
• Weeks 9–12: Cardarine 10 mg/day

In our experience, Ostarine does not cause virilization side effects in women when administering moderate dosages, such as 10 mg/day or less.

Disclosure: We do not accept any form of advertising on Inside Bodybuilding. We monetize our practice via doctor consultations and carefully chosen supplement recommendations, which have given our patients excellent results.

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The above user published his results on Reddit, where he reported losing 20 pounds after an 8-week cycle consisting of 10 mg/day of Cardarine and 20 mg/day of Ostarine.

A male Facebook user also shared his progress from this stack.

After 8 weeks on an Ostarine/Cardarine cycle, 25 pounds of fat lost and about 10 pounds of muscle added. I stuck to my diet and worked my butt off in the weight room. I’m going to crush it with RAD 150 in the fall.

Below are further before and after transformations following Ostarine-only and Cardarine-only cycles. This allows researchers to estimate the potential for results when combining the two substances.

Ostarine Gains

The outcomes from an Ostarine and Cardarine stack will be more notable than those from individual cycles. Consequently, users can anticipate more prominent fat reduction relative to the images below; nevertheless, no additional muscle development will occur since Cardarine is not anabolic.

The combination of Ostarine with a modest caloric deficit can provide significant fat reduction, as shown by the following Reddit user who consumed 20 mg daily for 45 days.

• This individual decreased his total body weight by 3 kg (7 lbs) while increasing his lean body mass.
• Consequently, the outcomes can be excellent when Ostarine is integrated with consistent weight training and a rigorous diet.

Cardarine Gains

The before and after picture illustrated below details a Reddit user’s results following a 12-week Cardarine cycle.

• This user’s body weight decreased by 40 pounds.
• During the first week, he consumed 10 mg/day, followed by 20 mg/day for the remaining 11 weeks.

Consequently, the concurrent use of Ostarine and Cardarine has significant impacts on body composition, including:

1. Subcutaneous and visceral adipose tissue reductions
2. Moderate hypertrophic muscle development

For women, the muscle gains from Ostarine and Cardarine will be comparable to the level of fat loss, resulting in a significantly lower body fat percentage and substantially larger musculature.

We have found Ostarine and Cardarine to be among the most powerful PED stacks for rapidly transforming a woman’s body composition.

Cardarine also has a profound effect on muscular endurance. Therefore, athletes or those performing regular cardiovascular exercise often experience vast improvements in their maximal oxygen uptake (VO2 max).

Side Effects

Our tests suggest that Ostarine and Cardarine are generally well-tolerated compounds and do not typically cause excessive adverse effects in either men or women. However, users should be cautious of the following side effects:

Testosterone Suppression

It has been established in our SHBG testing that Ostarine stimulates AR (androgen receptors), which results in a reduction of endogenous testosterone.

Some Ostarine users do not experience any obvious low testosterone symptoms in regard to mood, sex drive, and energy. However, these same individuals can exhibit 60–70% reductions in total testosterone following bloodwork analysis. Such decreases may be ascribed to free testosterone levels remaining within a normal range while total testosterone levels decline. This is not inherently harmful since free testosterone is the essential metric due to it being active and unbound.

We find testosterone levels typically recover several weeks after cycle cessation. For researchers who observe harsh testosterone suppression from Ostarine, they may administer a post-cycle therapy, such as Nolvadex or Clomid, to accelerate hypothalamic-pituitary-testicular axis (HPTA) recovery.

Liver Toxicity

Our anecdotal data suggests that Ostarine may elevate alanine transaminase (ALT) levels by 30% over the maximum typical range. This signifies moderate amounts of hepatotoxicity. To inhibit hepatic stress, the following supplements may be taken:

1. Tauroursodeoxycholic acid (TUDCA)
2. Silymarin (milk thistle)
3. N-acetyl cysteine (NAC)

In Dr. Thomas O’Connor’s experience with patients on Cardarine, he concludes that it is “hepatotoxic” and “more so than some anabolic steroids.”

Dr. O’Connor likens a standard Cardarine dose to causing “the same hepatic stress as a high dose of Anavar.”

Consequently, both men and women must exercise caution while combining Cardarine with Ostarine, since this combination will undoubtedly exert stress on the liver. By monitoring ALT and aspartate transferase (AST) levels during a cycle, users can more accurately calculate tolerable dosages.

The liver is a robust and resilient organ; thus, most individuals should have no difficulties with this stack. Nevertheless, those with compromised hepatic health should refrain from utilizing this cycle to prevent fulminant hepatic failure.

Blood Pressure

Ostarine, despite its reputation as a benign SARM, has the potential to induce labile hypertension.

We have seen Ostarine decrease high-density lipoprotein (HDL) cholesterol by 30% on mild dosages of 3 mg/day for 12 weeks. Research also indicates that blood lipids may be negatively affected by Ostarine in the short term (1).

Carcinogenic

A 2009 study found that administering large amounts of cardarine for extended periods of time can induce cancer proliferation in rodents (2). The rodents were given 5 mg/kg per day for 3 years, which translates to 500 mg/day for a 100 kg human.

However, this protocol is incomparable to the common doses that humans will take for cosmetic purposes, being 10–20 mg per day for a period of 3 months.

Dr. Anthony Hughes states that the researchers gave the rodents “megadoses.” He also says that in two decades, there has not been a single study demonstrating Cardarine to possess carcinogenic effects in humans. Dr. Hughes revealed that he has been utilizing Cardarine for 15 years and has personally noticed “no adverse effects.”

In order to more accurately evaluate the potential implications of cardarine-induced cancer proliferation, additional human research is required.

How to Consume

Ostarine and Cardarine are not FDA-approved compounds, and thus there is no established dosage guideline for men or women.

Typically, we administer ostarine orally at a concentration of 25 mg/mL.

For optimal bioavailability, users commonly let the liquid remain under the tongue for 15 seconds. This sublingual delivery method enhances bioavailability by enabling a more direct route into the bloodstream.

Ostarine has a half-life of 24 hours; thus, one dose per day is required.

Ostarine’s fast-acting nature allows for its use one hour before exercise. In such an instance, users may observe enhancements in:

• Muscular strength
• Aggression
• Energy levels
• Motivation

Similar to Ostarine, people frequently acquire Cardarine in liquid solution form (20 mg/mL) and administer it orally. Nevertheless, Cardarine is a stimulant to the central nervous system (CNS), so it may be beneficial for consumers to take their doses earlier in the day to prevent insomnia and nonrestorative sleep.

Given that Cardarine has a half-life of 16 hours, one dose per day is also acceptable.

Researcher Reviews

Those who have utilized an Ostarine and Cardarine stack posted these reviews on our private SARMs Facebook group.

I ran ostarine and cardarine as my first-ever cycle together; endurance improved a lot, muscle hardness improved, and I could eat very little without losing any gains. The only downside was that my libido dropped. I upped the ostarine to 20 mg; I was using 10 mg of both, but once I went to 20 mg ostarine, my desire ceased.

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Needed very little sleep. Felt great on about 6 hours.

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I’ve been stacking ostarine and cardarine for almost 3 weeks now. I’m on a light bulk, so my goal is basically to gain lean mass while maintaining or even losing some of my body fat. Conditioning went skyrocket, and according to other people, I look “bigger” even though they are not aware of my SARM cycle. I had 3 people say I look bigger, so I guess it’s working. I would suggest 20 mg cardarine/15 mg ostarine, increasing periodically until 25 mg (it’s working well for me, though each person is different, of course).

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Conclusion

An Ostarine and Cardarine stack is a potent fat-burning combination.

However, men are unlikely to build significant amounts of muscle hypertrophy on this stack, especially if adopting a calorie deficit diet. However, we have seen women build large amounts of lean muscle on Ostarine and Cardarine in conjunction with dramatic fat loss (3).

The risks of Ostarine and Cardarine appear to vary depending on the individual, with some users experiencing modest testosterone suppression, cholesterol, and liver enzyme fluctuations. However, other users can experience harsh effects causing hypertension, hepatotoxicity, and transient hypogonadism.

Therefore, further human research is necessary to fully understand the safety of both of these drugs in the short and long term before reaching definitive conclusions.

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