Bodybuilders use a range of anabolic-androgenic steroids, typically combining oral and injectable compounds in structured cycles that last 6 to 16 weeks. The specific drugs vary by goal: some are chosen for building mass, others for cutting fat while preserving muscle, and a few serve as a foundation for nearly every cycle. Here’s a breakdown of the most common compounds, how they’re combined, and what they do to the body.
Testosterone: The Foundation
Almost every steroid cycle starts with some form of testosterone. It’s the base compound because the body’s natural testosterone production shuts down when you introduce external steroids, and without replacement, you’d experience fatigue, muscle loss, and hormonal dysfunction. Bodybuilders choose between different “esters,” which are chemical modifications that control how quickly the drug releases into the bloodstream. Testosterone enanthate and testosterone cypionate are long-acting versions injected once or twice per week. Testosterone propionate is a short-acting version that requires more frequent injections but clears the body faster.
In a bulking context, testosterone is often run at higher doses to drive muscle growth directly. During a cutting phase, it’s kept at a lower “replacement” level to maintain muscle while other compounds handle fat loss. This flexibility makes it the single most widely used steroid in bodybuilding.
Oral Steroids for Mass
Oral steroids are popular for kickstarting a cycle because they take effect quickly, often within the first week or two, while slower injectable compounds are still building up in the bloodstream.
Dianabol (methandrostenolone) is probably the most iconic bulking oral. It promotes rapid weight gain through increased protein synthesis and water retention. Users commonly report gaining 10 to 15 pounds in the first four to six weeks of a cycle, though a significant portion of that is water. It’s almost always run for short periods because it stresses the liver.
Anadrol (oxymetholone) is the other heavyweight oral, prescribed medically at a starting dose of 0.5 to 1 mg per kilogram of body weight per day for conditions like anemia. In bodybuilding, it’s valued for dramatic strength and size gains, but it’s also one of the harshest compounds on the liver and blood pressure. Most users limit it to four to six weeks.
Both of these oral steroids pass through the liver before entering the bloodstream, which is why they carry a higher risk of liver strain compared to injectables. Blood work showing elevated liver enzymes is common during oral cycles.
Injectable Compounds for Bulking
Nandrolone (Deca-Durabolin) is a long-standing favorite for off-season mass building. It’s known for promoting joint lubrication and steady, quality muscle gains with somewhat less androgenic activity than testosterone. The downside is that it suppresses natural hormone production heavily and can take months to fully clear the body, making recovery more difficult.
Boldenone (Equipoise) is another injectable used in longer bulking cycles. It increases appetite and red blood cell production, which improves endurance and nutrient delivery to muscles. It’s considered a milder compound, but it requires long cycle lengths (often 12 weeks or more) to show full results because of its slow-acting ester.
Trenbolone: The Most Potent Option
Trenbolone stands apart from other steroids in terms of raw potency. It has strong anabolic effects with a limited androgenic profile relative to its muscle-building power. What makes it unique is its direct impact on body composition: research has shown that trenbolone induces fat breakdown by increasing the expression of enzymes involved in fat metabolism in the liver. This means it can build muscle and strip fat simultaneously, which is why competitive bodybuilders use it during both bulking and contest prep.
Trenbolone comes in two common forms. Trenbolone acetate is a short-acting version injected every other day, preferred because it clears the body quickly if side effects become intolerable. Trenbolone hexahydrobenzylcarbonate (sold under the brand name Parabolan) is a longer-acting version requiring less frequent injections. The side effects of trenbolone are notoriously harsh: insomnia, night sweats, elevated heart rate, aggression, and a persistent cough immediately after injection are all commonly reported.
Cutting and Contest Prep Compounds
When the goal shifts from building size to getting lean, bodybuilders rotate in compounds that preserve muscle on a calorie deficit without adding water weight.
Winstrol (stanozolol) is available in both oral and injectable forms. It gives a hard, dry look by not converting to estrogen, which means no water retention. It’s a staple in the final weeks before a competition. The trade-off is significant joint discomfort, since the lack of water retention extends to the joints, and additional liver stress from the oral version.
Masteron (drostanolone) is an injectable that provides a similar cosmetic hardening effect. It’s typically used by bodybuilders who are already fairly lean, since its visual benefits only become apparent at lower body fat levels. It also acts as a mild estrogen blocker, which reduces the need for separate anti-estrogen drugs.
Anavar (oxandrolone) is one of the milder oral steroids, often described as a “finishing” compound. It promotes modest strength gains and fat loss without dramatic size increases. Its relatively low liver toxicity compared to Dianabol or Anadrol makes it popular for longer oral runs of six to eight weeks.
Beyond Steroids: Growth Hormone and Insulin
At the professional level, steroid cycles are frequently combined with human growth hormone (HGH) and sometimes insulin. These aren’t steroids in the traditional sense, but they’re central to how elite bodybuilders build extreme size.
HGH promotes fat loss, recovery, and connective tissue repair. It works synergistically with steroids, amplifying their effects. Bodybuilders typically inject it daily for extended periods, sometimes six months or longer, because its effects on body composition develop gradually.
Insulin is the most dangerous compound in the bodybuilding pharmacology toolkit. It forces nutrients into muscle cells, creating a highly anabolic environment. Short-acting insulin, with an onset of about 5 to 30 minutes and a peak effect within 1 to 3 hours, is the type almost exclusively used in bodybuilding. Users consume at least 10 to 15 grams of fast-digesting carbohydrates for every international unit administered, because miscalculating can cause blood sugar to crash to life-threatening levels. Insulin-related deaths in bodybuilding, while not common, are well-documented.
How Cycles Are Structured
Bodybuilders don’t take steroids continuously at the same dose. The two main approaches are traditional cycling and “blast and cruise.”
Traditional cycling means running steroids for a set period (typically 8 to 16 weeks), then stopping entirely and using post-cycle therapy drugs to restart natural testosterone production. This approach is more common among recreational users.
Blast and cruise is a newer method favored by more serious competitors. The “blast” phase involves higher doses for roughly 6 to 12 weeks, followed by a “cruise” at a low testosterone-only dose for a similar length of time. The cruise phase gives the body partial recovery without fully coming off. Many competitive bodybuilders stay on this protocol year-round, sometimes for years.
Estrogen Control and Support Drugs
Several steroids convert to estrogen in the body, which can cause breast tissue growth (gynecomastia), water retention, and fat accumulation. To prevent this, bodybuilders use anti-estrogen medications alongside their cycles.
Anastrozole (Arimidex) is the most common, typically introduced in the second week of a cycle at 0.5 mg twice per week and continued for the duration. It works by blocking the enzyme that converts testosterone into estrogen. Exemestane (Aromasin) serves the same purpose but permanently deactivates the enzyme rather than temporarily blocking it. Tamoxifen (Nolvadex) takes a different approach by blocking estrogen at the breast tissue receptor specifically, and it’s used both during cycles and as part of post-cycle recovery to help restart natural hormone production.
Health Risks of Steroid Use
The cardiovascular damage from long-term steroid use is the most serious and well-documented risk. A study published in Circulation by the American Heart Association compared steroid users to non-users and found that users had significantly thicker heart walls and greater heart mass. The left ventricle, the chamber responsible for pumping blood to the body, weighed an average of 245 grams in steroid users versus 192 grams in non-users. This kind of enlargement forces the heart to work harder and increases the risk of heart failure, arrhythmias, and sudden cardiac death over time.
Steroid use also wrecks cholesterol levels. In the same study, 23% of steroid users had dangerously elevated LDL (“bad”) cholesterol above 160 mg/dL, compared to 13% of non-users. Many steroids, particularly oral compounds and trenbolone, suppress HDL (“good”) cholesterol to single-digit levels during a cycle, dramatically accelerating arterial plaque buildup.
Liver damage is primarily a concern with oral steroids that pass through the liver. Elevated liver enzymes during oral cycles are nearly universal, and prolonged use can progress to more serious conditions including bile duct obstruction and, rarely, liver tumors. Injectable steroids largely bypass this issue.
Other common side effects include acne, hair loss in those genetically predisposed, testicular atrophy from prolonged suppression of natural hormone production, mood disturbances, and fertility problems that can persist for months or years after stopping.
Legal Status
Anabolic steroids are controlled substances in the United States, the United Kingdom, Australia, and most other Western countries. Possessing them without a prescription is a criminal offense. The World Anti-Doping Agency bans all anabolic agents, including steroids, SARMs (such as ostarine, ligandrol, and RAD-140), and even compounds like clenbuterol, which is sometimes mistakenly considered “not a real steroid.” These bans apply both in competition and out of competition, meaning athletes are subject to testing year-round. In untested bodybuilding federations like the NPC and IFBB Pro League, steroid use is widespread and essentially assumed, even though the drugs themselves remain illegal to possess without a prescription.