A lot of guys have been asking me to clarify the theory behind this cycling technique, so here's a basic explanation.
What is "pulse" cycling? Pulsing is a method of dosing that is intentionally designed to avoid potential long-term side effects such as HPTA suppression and liver stress. This technique was originally developed in an effort to prevent the usual HPAA suppression experienced during long-term corticosteroid therapy in children. With pulse therapy, it was observed that the serious long-term side effects of chronic oral treatment were often prevented, and the short-term side effects like acne and mineral retention were typically much milder. This can also allow for higher doses to be used since the dosing is less frequent. Starting with this template, if one normally takes a product at 30 mg/day, that equals a total intake of 210 mg/week. While pulsing, one might typically take 40 mg of that same product on work out days only, 3 times per week. That calculates to 120 mg/week total, which is 90 mg less than usual. This provides the needed benefits of the product at arguably the most crucial metabolic times, which are just before and just after a work out. This offers a means of possibly attenuating the endocrine suppression that one might otherwise encounter on a standard cycle. In many cases, a conventional post cycle therapy should not be required after a typical 4 week pulse. However, while pulses of 6-8 weeks are permissible, a conventional post cycle therapy may still be prudent for some individuals. Idiosyncrasy seems to play a big role in regard to tolerance of duration, so general predictions obviously become tricky as duration increases.
Theoretically, if one doses every day in perfectly spaced intervals, one should achieve 100% effects, 100% short-term sides, and 100% long-term sides. If one doses every other day like the pulse protocol, one might better anticipate 60% effects, 75% short-term sides but only about 40% of the long-term sides. This means that if one would have gained 10 pounds on a standard 1 month cycle, one might instead only gain about 6 pounds per month pulsing. Since the time on is roughly only half when pulsing, the total length of the cycle can be doubled to basically 2 months. Using the same calculation, the net result would be a gain of 12 pounds over 2 months, instead of the 10 pound gain expected from the 1 month standard cycle. That means a greater net gain of 2 pounds per cycle, and perhaps a more permanent gain due to the slower rate of acquisition and longer time of reinforcement! For this reason, pulsing can be very economical on the body as well as the wallet, and offer a desirable alternative for conservative veterans just looking to stay in shape, or potential new comers exploring additional safety measures.
There are three common types of pulse:
1) EOD dosing (3-4 times per week)
2) 2 days on / 2 days off
3) 2 weeks on / 2 weeks off (2 wks is the longest viable on time consideration, no longer)
Depending on one's workout schedule, one of these options may offer optimal pulsing efficiency. On average, effective doses may typically be around 1.5x the normal daily dose of a standard cycle, and these doses are taken very close to one other. It's not essential that the last dose be administered before 6 pm, but the earlier the better for reducing suppression potential. Half the total dose can be taken pre work out, and the other half taken post work out. If an odd numbered dose is used, the greater of the 2 doses might best be taken pre work out. However, when pulsing non-methylated or fast acting supplements, the greater dose would instead be best utilized post work out based on half-life considerations. Individuals who are extremely sensitive to shutdown may even prefer to take the entire dose pre work out. When pulsing, dosing at least 3 day per week but not more than 4 day per week should foster optimal results.
There are a few miscellaneous nutrition considerations that would be wise to keep in mind. Having a quality, high carb/calorie post work out meal (or shake) is important to proper recovery, and ingesting sufficient protein especially on the off days doesn't hurt either. A cortisol antagonist like low dose DHEA (25-50 mg) may be helpful for slow healers or hard gainers. Some studies show that cortisol peaks in the morning and again in the mid afternoon, which might therefore be the ideal times for an anti-cort. An herbal or AI based test-boosting supplement used nightly (or at least on one's off nights) might prove very effective as additional insurance to discourage the possibility of suppression. SERMs with long half-lives probably require extra consideration and caution. One may observe that testicular volume and/or testosterone levels reset slightly above previous baseline at the end of 2 consecutive off days, or at the end of the cycle itself. This phenomenon is called 'bounce' back. This seemingly paradoxical bounce appears to reflect the body's short-term homeostasis effort, and acts somewhat like a built-in pct with this method. It's also good to remember that the smaller number of dose exposures likely means faster liver clearance of your supplement. Liver ancillaries (like healthy oils and anti-oxidants) are not contraindicated, but Milk Thistle in high doses could act counter productive to gains. Therefore, if you elect to use liver protectants, reserving them for off days only might be good middle ground. As always, I suggest that one only consider using legal, commercially available nutritional supplements, and always consult a physician prior to use of any supplement. Cycle safe!
Example of a 3x/wk pulse M,W,F:
Example of a 4x/wk pulse Sat, Sun, Wed, Thur: