The maxim “Eat for growth” is familiar to competitive bodybuilders. But what about “Cycle for growth”?

No, we aren’t talking about the Tour de France pedal-pushing crowd. In bodybuilding, cycling refers to the practice of using one or more nutritional supplements for a specified period, discontinuing them, and starting another set. Cycling is assumed to have three purposes: to optimize results in a given training phase; to prevent harmful side effects by giving the body a rest; and to overcome the body’s tolerance for the supplements. Typical supplementation cycles run between four and 12 weeks. There are hundreds of supplements available, and the choices can be dizzying. 

Supplements Can Complement Training Cycles

Whether you’re a competitive bodybuilder or you just want to have a great physique, your goal is to gain lean body mass. How much mass you can expect to gain is largely determined by training and genetics. In order to gain mass, you have to challenge the muscles to lift more weight. Incorporating cycles of training for muscle hypertrophy (reps of eight to 12 per set) with cycles of muscle strength (reps of four to six per set) will not only allow for greater muscle gains but also prevent injuries.

What to Stack

Creatine, glutamine, and beta-hydroxy beta-methylbutyrate (HMB) are the best-studied supplements used in this phase of training that appear to increase muscle mass associated with a resistance-training program. There is some evidence that using multivitamins and branched-chained amino acids (BCAAs) during this phase may be beneficial. Other supplements that are commonly cycled to improve lean muscle mass are testosterone-stimulating agents like DHEA, Tribulus terrestris (which you’ll find in Nutrex Research’s Vitrix and MHP’s T-Bomb II), and 6-OXO (4-Androstene-3,6,17-trione) (the active ingredient in ErgoPharm’s 6-OXO), and dietary elements like vanadyl. However, more study of these agents is needed to verify their effectiveness. 

To gain body mass, you have to increase your calories while maintaining adequate protein intake. If you have a tough time growing muscle, you may want to cycle weight gainers and protein supplements. Finally, the most difficult stage in competitive bodybuilding is the “cutting” phase, which is when bodybuilders shed body fat to reveal the results of their months of hard work. Caffeine (which is found in such popular supplements as Prolab Caffeine, PrimaForce Caffeine, and Mega-Pro International Caffeine Alert), aspirin, and synephrine are typical agents that are cycled into a cutting stack. These thermogenic agents are used to enhance weight loss. 

Cycling to Prevent Side Effects

Although supplements are generally safe for most individuals, they do carry some risk of side effects. Continual use may have harmful cumulative effects. Prolonged use of creatine, amino acids, protein products, and mineral supplements may cause kidney or gastrointestinal disturbances, especially if the amounts used exceed those recommended. If used for prolonged periods, prohormones such as DHEA may have a similar side-effect profile as anabolic steroids: namely, cholesterol elevation, liver dysfunction, baldness, and sterility. Continuous use of thermogenic supplements can cause dehydration, elevated blood pressure, insomnia, nervousness, irritability, and artery constriction in the brain and heart. 

Cycling to Prevent Tolerance

There’s a lot of talk among bodybuilders about changing supplements to “shock” the muscles into growth. What they’re referring to is the prevention of the buildup of supplement tolerance. This concept may be more urban gym myth than fact. It’s clear that more clinical research is needed in this area, and only careful experimental design will reveal whether or not athletes reach a level of tolerance with supplement use in the presence of progressive training. 

Some Recommendations

Although there are no standard recommendations among exercise physiologists with regard to supplement cycles, the following guidelines are based on sound drug physiology:

• Let your type of training, physique goals, and common sense dictate your supplement-cycle choices.


• Supplement cycles do not take the place of sound nutrition, hard training, and adequate rest to achieve increased muscle mass or a lean physique.


• A single cycle should not exceed a 12-week period, and a four-week period should be used between cycles.


• Review the list of banned substances before entering a sports competition. Many supplements are banned by sports organizations.


• Before using supplements, ask your health-care provider about them.
  

—Marie President, M.D.