How a cycle is structured - and what to track across it

Q: What are the phases of a steroid cycle?

Most structures come down to time-boxed windows people give names to. A blast is a higher-output window; a cruise is a lower, maintenance-level window between blasts; an on-cycle followed by a full off period is the more traditional pattern; and the recovery or post-cycle phase is the window after compounds clear, when the body's own production is meant to come back. These are labels for dated windows, not fixed recipes - the point of naming them is so that anything you track (labs, weight, side effects) can be read against the phase you were in rather than as one undifferentiated blur.

Q: Why does compound half-life determine when PCT starts?

Post-cycle recovery only makes sense once the suppressive compounds have actually left your system. Each ester clears on its own schedule - a short ester like a propionate is largely gone within days, while a long ester like a decanoate or undecanoate can take weeks. As a rule of thumb, a compound is considered mostly cleared after about three half-lives and effectively cleared after about five. The longest-clearing compound in a stack sets the earliest sensible starting point, which is why timing is calculated from the slowest ester's last dose, not from the end of the cycle on the calendar. Actual timing is a clinical decision; this page explains the mechanism, not a protocol.

Q: What should you track during a cycle?

The high-value things are the ones you cannot reconstruct later from memory: which compounds ran and when, doses and injection dates, bloodwork over time (so you can see markers move rather than guess), weight and body-composition changes, and any side effects as they appear. Keeping these on one timeline is what lets you answer the two questions that actually matter next time - what did I run, and how did it go - and lets a clinician read your labs in the context of what you were taking when the blood was drawn.

Q: What bloodwork matters across a cycle?

A baseline panel before or at the start gives every later reading a personal reference point. A mid-run check (often around weeks 6-8) commonly looks at hematocrit and lipids alongside hormone levels, because those are the markers that tend to drift under higher androgen load. An end-of-run panel captures peak-exposure values, and a recovery panel several weeks after everything clears shows where your own baseline actually settled - the LH, FSH, and testosterone picture that indicates whether the axis has come back. The specific markers and timing are between you and a clinician; the value of tracking is putting labs on the same timeline as the protocol.

Q: Is blast and cruise the same as a traditional cycle?

No. A traditional cycle runs compounds for a fixed number of weeks and is then followed by a full off period and a recovery phase, with the goal of returning to natural production. Blast and cruise instead alternates higher-output blasts with lower, maintenance-level cruises without a true off period - so natural production stays suppressed continuously. That is a meaningfully different risk profile, and the trade-offs (ongoing suppression, cardiovascular and lipid load, fertility) are exactly the things worth tracking and discussing with a clinician rather than treating as settled.

People who run anabolics tend to think in phases - a blast, a cruise, an off period, a recovery window - but the phases only become useful when the things you track are tied to them. This is a plain, educational overview of how those windows fit together, what is worth logging across a run, why compound half-lives decide when a recovery phase can even begin, and which bloodwork tends to matter. It contains no doses, schedules, or protocols - it explains structure and mechanism so the decisions you make with a clinician are better informed.

By OptiPin Editorial·Last updated July 2026

Phases are

Dated windows

PCT timing from

Slowest ester

Mostly cleared

~3 half-lives

Track on

One timeline

TL;DR

• Phases are just named, dated windows. Blast, cruise, off, recovery - the value of naming them is that labs, weight, and side effects can be read against the phase you were in.
• Half-lives drive recovery timing. A recovery phase only makes sense once the suppressive compounds clear; the slowest ester's last dose sets the earliest sensible start, not the calendar end of the run.
• Track what you can't reconstruct later. Compounds and dates, bloodwork over time, weight, and side effects - on one timeline.
• Bloodwork carries the whole thing. Baseline, a mid-run check, end-of-run, and a recovery panel - each answers a different question.
• This is educational. No doses or protocols here. Anabolic use carries real cardiovascular, hormonal, and fertility risk; decisions belong with a clinician.

Phases are named windows, not recipes Framing

Almost every way of running anabolics comes down to time-boxed windows that people give names to. A blast is a higher-output window. A cruise is a lower, maintenance-level window that sits between blasts. The more traditional structure is an on-cycle for a set number of weeks followed by a full off period. And the recovery or post-cycle window is the stretch after compounds have cleared, when the body's own production is meant to come back.

The names matter less than the fact that each one is a dated window. On its own, "my testosterone read high in April" tells you little; "my testosterone read high in April, six weeks into a blast" tells you something you can act on. That is the whole reason to structure a run into phases: so every data point you collect - a lab value, a weight change, a side effect - can be read against the context it happened in rather than as one undifferentiated blur. A tool that tags those windows is doing the same job as the phase labels on this page, just with dates attached. In OptiPin, that is what a cycle is - a container that groups a run's compounds and phases onto one timeline.

Why half-lives decide when recovery can start Strong mechanism

The single most misunderstood part of cycle structure is timing - specifically, when a recovery phase can begin. The intuitive answer, "when the cycle ends," is wrong, because the compounds do not leave your body when the calendar says the run is over. They leave on their own schedule, set by the ester attached to each one.

An ester is a chemical chain that slows how fast a compound releases after injection - the longer the ester, the longer the tail. A short ester such as a propionate is largely gone within a few days; a long ester such as a decanoate or an undecanoate can take weeks to clear. The standard way to reason about this is the half-life: the time for roughly half of what is present to be eliminated. After about three half-lives a compound is considered mostly cleared, and after about five it is effectively gone.

That is why a recovery phase is timed from the last dose of the slowest-clearing compound in the stack, not from the end of the cycle on paper. If a run finishes on a long ester, the suppressive signal is still present for weeks afterward - starting recovery before it clears means working against a compound that is still telling the axis to stand down. You can see how any given ester decays with our half-life calculator, and the axis-recovery side of this is covered in depth in coming off TRT - how a restart works. The exact timing is a clinical decision; the mechanism is what makes the decision make sense.

What's worth tracking across a run Practical

The useful rule is to track the things you cannot reconstruct from memory later. Six months on, you will not accurately recall which week you added a compound, what your hematocrit was mid-run, or when a side effect first showed up - and those are exactly the details that make the next run better informed. In practice that means:

• Compounds and dates - what ran when, doses, and injection dates, so the timeline is real rather than remembered.
• Bloodwork over time - readings on a timeline so you watch markers move, instead of comparing two isolated numbers.
• Weight and body composition - the outcome side, read against the phase it happened in.
• Side effects as they appear - a short running log beats trying to remember, and it is what a clinician can actually use.
• Injection sites - so rotation is deliberate rather than accidental.

Keeping these on one timeline is the point. It is what lets you answer the two questions that actually matter for the next run - what did I run, and how did it go - and it is what turns a folder of screenshots and a notes app into something a doctor or coach can read. This is the job OptiPin's tracking is built for: compounds, doses, labs, weight, and phases on a single screen.

The bloodwork that carries a cycle Strong evidence

If you track only one thing, track bloodwork - and track it at the right moments, because the same panel means different things at different points in a run. Four checkpoints tend to matter, each answering a different question:

Baseline

A panel before or at the start gives every later reading a personal reference point. Without it, you are comparing mid-run numbers to population ranges instead of to your normal, which is far less informative.

Mid-run

A check partway through - often around weeks 6-8 - commonly looks at hematocrit and lipids alongside hormone levels, because those are the markers that tend to drift under higher androgen load. This is the checkpoint that catches a problem while there is still time to respond to it.

End of run

A panel near the end captures peak-exposure values before things start to change - a record of where the protocol actually landed you.

Recovery

A panel several weeks after everything clears shows where your own baseline settled. This is the LH, FSH, and testosterone picture that indicates whether the axis has come back - the same recovery question covered in the restart guide. Our bloodwork guide goes through the individual markers.

Blast-and-cruise vs a traditional cycle Trade-offs

These two structures get talked about interchangeably, but they carry different risk. A traditional cycle runs compounds for a fixed number of weeks, then a full off period, then a recovery phase, with the explicit goal of returning to natural production. Blast and cruise instead alternates higher-output blasts with lower, maintenance-level cruises and never fully comes off - which means natural production stays suppressed continuously, and the recovery phase that a traditional cycle builds in simply does not happen.

That is not a small distinction. Continuous suppression changes the fertility, cardiovascular, and lipid picture, and it is the reason ongoing tracking matters more, not less, for anyone cruising - the markers that a traditional cycle would let reset between runs are instead under constant load. None of that is a reason to treat one structure as safe; it is a reason to know which one you are running and to watch the things it stresses. These are conversations for a clinician, informed by your own data.

The honest part

Anabolic use carries real risks - cardiovascular strain, lipid and hematocrit changes, hormonal suppression, and fertility effects that are not always reversible. This page explains how cycles are structured and what is worth tracking; it is not medical advice, and it deliberately contains no doses or protocols. Tracking your own data well is a harm-reduction step, not a substitute for a clinician. If you are running or planning to run compounds, do it with medical supervision and serial bloodwork.

Track a cycle on one timeline

OptiPin groups a run's compounds, phases, doses, and bloodwork onto a single timeline - with estimated clearance windows from each compound's half-life and a phase-aware lab checklist. It is your own data, on your device, ready to hand to a clinician. iOS only.

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Frequently asked questions

What are the phases of a steroid cycle?

Most structures come down to time-boxed windows people name: a blast (higher-output window), a cruise (a lower, maintenance-level window between blasts), an on-cycle followed by a full off period, and a recovery or post-cycle window after compounds clear. They are labels for dated windows, not fixed recipes - naming them lets anything you track be read against the phase you were in.

Why does compound half-life determine when PCT starts?

Post-cycle recovery only makes sense once suppressive compounds have cleared. Each ester clears on its own schedule - short esters within days, long esters over weeks. A compound is considered mostly cleared after ~3 half-lives and effectively cleared after ~5, so timing is calculated from the slowest ester's last dose, not the calendar end of the run. Actual timing is a clinical decision.

What should you track during a cycle?

The things you cannot reconstruct later: which compounds ran and when, doses and injection dates, bloodwork over time, weight and body-composition changes, and side effects as they appear. On one timeline, this answers "what did I run and how did it go" and lets a clinician read your labs in context.

What bloodwork matters across a cycle?

A baseline before/at the start, a mid-run check (often weeks 6-8, commonly hematocrit and lipids with hormones), an end-of-run panel at peak exposure, and a recovery panel several weeks after everything clears to see where your baseline settled (LH, FSH, testosterone). Specific markers and timing are between you and a clinician.

Is blast and cruise the same as a traditional cycle?

No. A traditional cycle runs for fixed weeks, then a full off period and recovery phase aimed at returning to natural production. Blast and cruise alternates blasts with maintenance cruises without a true off period, so natural production stays suppressed continuously - a different risk profile worth tracking and discussing with a clinician.

Coming off TRT / restart · Half-life calculator · Bloodwork to monitor · TRT protocols · Estradiol in men · Side effects · Medication library