01 · PROGRESSIVE OVERLOAD
History becomes the target.
Every exercise carries a LAST line: what you did last time, sitting above the sets you're about to do. The session isn't a blank form; it's a number to beat.
Progression is chosen per exercise, as a module, and each method changes how the logger behaves and how progress is measured. Myo-reps get their own model: an activation set to about one rep short, then mini-sets of three to five, pushing the session total past last time. Top out, add load. A log that takes myo-reps as free text measures progress as though every set were straight; Delta models the method, and the measure follows it.
Incline Press
STRAIGHT · 3 SETS
LAST
155×10 · 155×10 · 155×10 · 155×7 · ★ PR
Straight
Top / back-off
Drop
Myo-reps
Rest-pause
Myo-reps in one line: 42.5 lb · activation 15 · minis 4·4·4·3 = total 30. Next session, beat 30.
02 · WORKOUT PROGRAMS
The next session is already loaded.
Your program's days sit next-up on top, last-done at the bottom. Drag to reorder, or log an off-program session. Pick from 4-Day Upper / Lower, 3-Day Full Body, Push / Pull / Legs, 2-Day Upper / Lower, or build your own, or import a shared program from a code with a preview before you run it.
Switching programs never loses your numbers.
Upper ANEXT UP8 exercises · 3 myo
6 days ago
Lower A
5 exercises · 2 myoUpper B
7 exercises · 3 myoRename days, reorder exercises, set a backup per lift, choose the method, set the rest: all in the day editor.
03 · WORKOUT LOGGING
Effort goes on the record.
Sets are logged at one to two reps in reserve, the program's target, or marked as taken to failure. Rest timers adjust per exercise. A lift can be held at maintenance without breaking the record. And when the machine's taken, the backup you pre-chose is one tap away.
Discard a bad day without ceremony. Finish and the Coach reads the session before you've racked the plates.
1
lb155
reps10
✓
+ add set
−⏱ Rest 2:00+
⇄ Machine taken? Use DB Press
○ Mark as maintenance / hold
04 · EXERCISE LIBRARY
The right lift, not just a lift.
The picker filters by equipment and body part, and custom exercises are first-class. The catalogue reconciles every lift you've ever logged, so history never splits across two names for the same movement.
There's a joint-friendly filter, too, for lifters training around what the years left behind. It selects machine and cable movements.
Barbell
Dumbbell
Machine
Cable
Bodyweight
Joint-friendly
Belt SquatMACHINE · QUADS
Machine Chest PressMACHINE · CHEST
+ Create a custom exercise
05 · WORKOUT HISTORY
History follows the lift.
Rename a lift, switch to the machine variant, or change programs, and a conventional log starts a fresh record. Years of lineage quietly fork. Delta reconciles the catalogue instead: every session you save in Delta keeps its date, exercises, duration and PRs, and each lift's Delta history follows it through renames, variants and program switches. Every number you've earned here comes with you.
Lower B
Aug 21 · 2:14 PM · 6 exercises · 48:32 · 2 PRs
Upper B
Aug 20 · 6:05 AM · 7 exercises · 55:10
Upper A
Aug 17 · 6:12 AM · 8 exercises · 58:41 · 2 PRs
Sample figures.
06 · STRENGTH PROGRESS TRACKING
Beating the logbook is the only streak.
Not sessions completed. A streak measures attendance, not strength. Delta counts the proportion of lifts you trained recently that set a new best. Weekly volume by muscle is counted in hard sets against a hypertrophy landmark, with the counting rules for myo-reps and drop sets stated, and a note that muscle mapping is approximate.
A readiness-driven lighter week counts as on-plan, not a miss.
4 of 11
lifts with a pre-break best are past it; 7 still re-establishing
Avg +27.6% across all 15 loaded lifts since this athlete started Delta · 82 times the logbook was beaten · 24 movements trained
On plan 7 of the last 8 weeks. The lighter week was readiness-driven and counted as on-plan.
Belt Squat≈ 238 lb · 8 sessions+98.3%
Seated Cable Rows≈ 256 lb · 15 sessions+50.9%
Leg Press≈ 173 lb · 5 sessions+37.6%
Estimated 1RM, biggest movers first, since this athlete started Delta. Sample figures.
07 · TRAINING RECAP
See what eight weeks actually moved.
One card: sessions, the share of lifts beating the logbook, the recovery week you took on purpose, and your biggest mover. Built to screenshot and share.
DELTA · LAST 8 WEEKS
4 of 11 lifts past your pre-break best
31
sessions
60%
of lifts beat the logbook
82
times you beat your last
1
recovery week, on purpose
Biggest mover: Belt Squat +98.3%
No streaks. No vanity PRs. Just steady, honest work.
08 · BODY COMPOSITION TRACKING
Strength leads. Composition lags.
PRs are the leading signal that training is working; body composition is the lagging proof it's becoming muscle. A single scan swings with hydration. Read the line, not the dot. Add scans by hand, import CSV, or sync from Health.
Weight194.7 lb▲ 1.1 lb/wk
Body Fat18.4 %▼ 0.0 %/wk
Lean Mass142.2 lb▼ 0.5 lb/wk
28-day trend: weight up, lean mass down, fat flat. The scale is moving and the composition isn't. Delta says so instead of calling it a bulk.
09 · AI COACH
It reads your data, then makes a call.
Every other part of Delta shows you a number and leaves the judgment to you. Coach is the one surface that reads your readiness, your logged history, your recovery state and your program together, makes the judgment, cites what it used, and tells you what to do about today.
Here is a real answer, at full length.
Should I push or deload this week?
Your readiness is at 47, below your baseline of 50, and you're reporting soreness at a 3, well above your usual 1. The drivers: sleep came in short (6.3h vs your 7.3h average), resting HR is actually good, but HRV, wrist temp, and respiratory rate are all drifting off your normal. Mixed picture; the soreness signal is the loudest one here.
On the other side, you're beating the logbook at a 60% rate over the last two weeks, strong progress, and you haven't taken a lighter week in 8 weeks. That's the real tell: you're accumulating work without a break to consolidate it.
Deload this week. Not because you're broken; a lighter 4–5 days now lets you come back harder and actually cash in the momentum. Drop volume ~30–40%, drop loads slightly, keep the movements the same.
WHAT IT USED
readiness 47 vs baseline 50
sleep 6.3h vs 7.3h avg
soreness 3 vs usual 1
logbook rate 60% / 2 wk
8 wk since a lighter week
Every claim in the answer is cited from your own log and your own night. General advice never appears, because Coach has something better to reason from.
Coach proposes; it does not take over. Watch-list a lift and it tracks it. Post-session observations arrive as suggestions you accept or dismiss. Turn insights off entirely and off means off.
Watch-list a lift
Post-session observations
Injury-driven substitutions
After sessions · before & after · off
An optional profile shapes advice only; it never enters any number.
Coach comes with Delta Plus. If you're on a trainer's plan, you can add it by upgrading to Plus. What Coach sends to answer you is stated in Principles.
10 · DAY ONE
What day one looks like.
No history yet, no baseline yet. Each tab tells you what it is waiting for.
READINESS
No baseline yet
Delta learns your normal over the first week or two of nights. Until then, it says so instead of guessing.
PROGRESS
Nothing to beat yet
Your first session becomes the line every later session has to pass.
TRAIN
Pick a program
4-Day Upper / Lower is loaded to start. Change it, build your own, or import one. Your numbers follow the lifts either way.
11 · PRINCIPLES
What Delta does with your data and your progress.
YOUR DATAYours. On your device, in your iCloud backups, synced to your Delta account, and exportable as JSON. One exception: using Coach sends your training data to a model provider to answer you, and the app names everything it sends before you agree.
TRAINERSLink with a code, see exactly what a trainer receives before anything is shared, end it any time. Body data never reaches a trainer, whatever the settings say. The readiness score, and the signals behind it, never reach a trainer.
HEALTHDelta reads what you grant and says plainly what it can't see: iOS's own permission switches belong to iOS.
PROGRESSNo streaks and no dark patterns around progress. A lift counts as progress only when it passes your proven best.
