A missed week of the gym costs you nothing in Zyra Workouts: the program is a sequence of cycles, not a calendar, so no day is rescheduled, no target is regenerated and no penalty is applied. The only thing the app learns from is the next session you log — and if that session falls short of a target's rep floor, the progression engine steps the load down one increment for the time after. What a week costs in training terms is a separate question: in trials of short breaks, one to three weeks off cost no significant muscle size, while some strength and power measures dipped415. This page keeps the two apart.
Zyra Workouts is in development and not yet on the App Store; the screens described here may change before release.
What a week actually costs
The app cannot tell you what happens inside your body during a week off. Zyra Workouts is a training log; it measures what you lift, not what you are made of. What trials of short breaks found is in the research section further down.
What the log can tell you is what a week costs *in the plan*:
| What | Effect of a missed week |
|---|---|
| Program schedule | none — the next unfinished day of the current cycle is still next |
| Cycle targets | none — cycle 3's RIR is still cycle 3's RIR when you get there |
| Records (1-RM, volume, reps) | none — nothing expires |
| Weekly set counts | the missed week shows as zero sets; the current week starts fresh on Monday |
| Progression recommendations | unchanged until you log a session; then rebuilt from that session |
| Trajectory (30-day e1RM) | only sessions inside the window count; a gap simply leaves fewer of them |
That last row deserves a note: the dashboard's trajectory label needs at least two sessions of an exercise in the last 30 days to show a percentage. Come back after a long gap and it reads 0% until there is something to compare.
Why a cycle-based program does not punish you
A cycle is one pass through the program's days. The app advances to the next day when you finish the current one, and to the next cycle when you finish the last day. There is no clock behind it. If you trained day 1 and day 2 of a three-day cycle and then missed a week, day 3 is still waiting, with the same targets it had.
This is a deliberate design: the source notes say a missed workout does "nothing, programmatically" — programs are cycle-based, so skipped days do not reschedule, penalise or regenerate the program. Resuming needs no action; you start the next unfinished day.
The RIR ramp inherits this. Effort rises by *completed* cycles, so a week off in cycle 2 does not drop you into cycle 3's harder targets on return; it leaves you in cycle 2.
In plain terms: the app's answer to "what now?" is "the same next session as before, whenever you do it".
Coming back one step lower
The progression engine has no memory of the gap. It reads the last completed working sets of each exercise — from whenever they happened — and compares each to the cycle's target. Three outcomes:
- progress — reps above the ceiling (midpoint of the rep range + RIR): add one load step
- hold — reps inside the range, at or under the ceiling: same weight
- backoff — reps below the rep floor:
weight − step, reps reset to the floor
The step depends on the equipment: for a barbell it is two of your smallest plate (2.5 kg with 1.25 kg plates), for dumbbells, machines and cables it is a fixed 2 kg, and bodyweight exercises have no load step (reps are the only lever).
Suppose your last back squat before the break was 100 kg × 8 against a 6–10 @ RIR 2 target (ceiling 10). The recommendation on return is hold: 100 kg × 8, because 8 is inside the range. You squat, and it goes 100 kg × 5. Five is under the floor of six, so the next recommendation is backoff: 97.5 kg × 6 — one plate pair off, reps back to the floor. The session after that decides again from what you actually did. The same logic on a barbell bench press at 80 kg × 4 against the same target gives 77.5 kg × 6.
Nothing in that sequence is a punishment. It is the same rule that runs every session; a short first session back is just a set of numbers it responds to. A yellow wand on the set shows the rule it applied, in the form "Last time 100 kg × 5 · target 6–10 @RIR 2 (ceiling 10) → under the rep floor, backing off to 97.5 kg × 6".
If you would rather choose the first load back yourself, two options are built in. The first-cycle deload position makes the opening cycle of each block lighter (see how to deload), and any recommendation can be overridden by typing a different weight — the engine reads what you log, not what it suggested. This is arithmetic, not a trial result: it describes what the engine does with a short session, not what a week off does to a person.
What short breaks do, in the research
The research on time off is called detraining: stopping training after a period of doing it. The short answer from the studies is that muscle size holds up over one to three weeks, while some strength and power measures slip.
The big picture. A 2013 meta-analysis pooled 103 studies of people who stopped resistance training3. Every part of muscular performance fell: submaximal strength (SMD −0.62), maximal force (−0.46) and maximal power (−0.20). SMD, the standardised mean difference, is the change divided by the spread between people. The losses grew with the length of the break, and were larger in people over 65 and in people who were otherwise inactive3. Those pooled numbers mix breaks of all lengths, so a single week sits at the small end.
Change in muscular performance after stopping resistance training · SMD
One week off, in trained lifters. In a 2024 randomised trial, 39 resistance-trained young adults followed a 9-week, high-volume program4. One group took week 5 completely off lifting; the other trained straight through. Muscle thickness, endurance and jump power ended up similar in both groups. Strength gains were probably smaller with the week off: the posterior probability that continuous training did better was 0.851 for the 1RM squat and 0.924 for isometric knee strength4. The deload page covers this trial in more detail.
Three weeks off, in young men. Two small trials in young men (previously untrained in the first) used bench press training12. After 6 weeks of training, one group stopped for 3 weeks and then resumed. Muscle cross-sectional area and 1RM did not drop significantly during the break, and after 15 weeks both groups had improved by similar amounts1. A 24-week version, with three 6-week training blocks separated by 3-week breaks, again ended with similar muscle size and strength gains to continuous training2.
Two weeks off, in elite powerlifters. A 2026 study measured 20 elite male powerlifters before and after a 14-day break5. Jump reactive strength, rate of force development in a pull and sprint performance fell significantly. Muscle thickness and cross-sectional area did not change significantly5.
What regrowth after a longer layoff looks like is covered in is muscle memory real, and the myth that muscle changes into fat in does muscle turn into fat.
In plain terms: in these studies a week or two off did not cost measurable muscle. What slipped first was strength and power, and in the week-off trial the gap in strength gains was modest.
The studies at a glance
| Study | Who was studied | Key result | Year |
|---|---|---|---|
| Ogasawara et al., *Clin Physiol Funct Imaging*1 | 15 untrained young men, bench press, 3 weeks off after 6 weeks | No significant loss of size or 1RM in the break; similar gains at 15 weeks | 2011 |
| Ogasawara et al., *Eur J Appl Physiol*2 | 14 young men, 24 weeks, 3-week breaks every 6 weeks | Similar muscle size and strength gains to continuous training | 2013 |
| Bosquet et al., *Scand J Med Sci Sports*3 | Meta-analysis of 103 studies of stopping training | All strength and power measures fell; more with longer breaks and in over-65s | 2013 |
| Coleman et al., *PeerJ*4 | 39 trained young adults, 9 weeks, week 5 off vs continuous | Similar muscle growth; strength gains probably smaller with the week off | 2024 |
| Yılmaz et al., *J Strength Cond Res*5 | 20 elite male powerlifters, 14 days off | Jump, pull and sprint measures fell; muscle size change not significant | 2026 |
Limits worth knowing
- Small samples. 14 to 39 people per trial; small changes in muscle size are hard to detect with groups this size.
- Different people. Young men in the 2011 and 2013 trials, trained young adults in 2024, elite powerlifters in 2026; results may differ in older adults, who lost more in the meta-analysis3.
- No control group in the powerlifter study. It measured one group before and after, as far as the abstract shows5.
- Abstracts only for the meta-analysis, the 2011 and 2013 trials and the powerlifter study; the 2024 trial was read in full.
- Funding. The 2024 trial was funded by a fitness company that had a role in its design and write-up4.
Latest research
The newest study we opened is the 2026 powerlifter study, published in September 20265. After 14 days off, 20 elite male powerlifters showed significant drops in jump reactive strength, force development in an isometric pull and sprint performance, along with changes in muscle activation. Muscle thickness and cross-sectional area did not change significantly. The authors call their reading, that early losses are more about the nervous system than about muscle size, "tentative". The full text is behind a paywall; we read the abstract only.
The short version
A missed week changes nothing in the program: cycles wait, records stand, targets stay. The progression engine rebuilds its recommendations from the first session you log on return; land under the rep floor and it takes one load step off (2.5 kg on a barbell, 2 kg on a stack or dumbbell) and resets reps to the floor. Prefer a gentler restart? Set the deload to the first cycle. In the research, breaks of one to three weeks cost no significant muscle size, while some strength and power slipped45. The rules the whole program runs on are in the program guide.
Educational overview only — training guidance, not medical advice.
