It has been the biggest month since launch. Here is what changed since the March update.
IntervalCoach is now on iPhone
The most-requested feature since day one is live. The native iOS app gives you the full daily briefing with push notifications, Coach+ chat, activity analysis, the dashboard and calendar, and one-tap post-workout feedback — all optimized for the phone with instant loading. Sign in with Intervals.icu and everything carries over: data, settings, and subscription.
Download from the App Store → — or read the launch post for the full tour. Universal Links also mean tapping any intervalcoach.app link from Mail, Messages, or Safari opens the app directly if you have it installed.
Apple Health is now a first-class data source
With the latest iOS app update, HRV, resting heart rate, respiratory rate, blood oxygen, wrist temperature, sleep phases, VO₂ Max, heart rate recovery, body weight, body fat, and menstrual phase all flow into the same readiness pipeline Whoop has always driven. You get recovery-aware coaching with just an Apple Watch — no Whoop strap required. If you have both, Whoop stays primary and Apple Health fills the gaps. Anything compatible also mirrors back to Intervals.icu so your wellness history there stays complete. Read more →
Three new signals come along for the ride:
- Heart rate recovery slowing vs your 14-day baseline — a subtle overreaching cue HRV alone can miss.
- VO₂ Max declining vs your 30-day peak — an early burnout warning.
- Menstrual phase auto-detected from Apple Health and surfaced as info-level context (phase-aware signal interpretation is next on the roadmap).
A new Biometrics section in the Health Details sheet shows tiles for resting HR, HRV, sleep, wrist temperature, SpO₂, and respiratory rate — each with a baseline gauge and a Normal / Higher / Lower pill, so you see today's number and where it sits relative to your personal 30-day baseline.
Public profiles, milestone badges, and peer benchmarks
You can now share your training with a public profile. Toggle it on in Settings > Account, customize your handle, and share the link. Your profile shows earned badges, peak fitness, training stats, and a GitHub-style heatmap colored by your primary sport.
Training milestones: earn badges for volume (Century Day, Big Week, Monster Week), consistency (7-day and 30-day streaks, Plan Follower), fitness gains (FTP Bump, New Peak CTL, Power Surge), recovery, and multi-sport training. Repeatable challenges include Monthly Century, Perfect Month, and Annual Warrior, plus tenure milestones at 3 months through 2 years. Unearned badges show progress bars; earned ones show what percentage of athletes have unlocked them. You get an email when you unlock a new one.
Performance Benchmarks is a new Max feature: toggle peer comparisons on the Analytics page to overlay P50 reference lines on your CTL, eFTP, power curve, weekly TSS, and running pace charts. Filter by age group and sex for a relevant peer group. Coach+ for Max subscribers can also answer benchmark questions directly — "how do I compare to riders my age?", "what's my percentile for 20-min power?".
Smarter daily adaptation
This is the biggest intelligence upgrade of the month. Daily workout adaptation now uses the full readiness signals engine. Previously only a big TSB drop or red recovery would change your workout — yellow recovery combined with short sleep, HRV instability, or training monotony went unaddressed even when the dashboard already recommended capping intensity. Now when signals cap your day, the coach swaps the workout type (VO2max → Tempo, Threshold → Sweet Spot) instead of just scaling TSS, extends your warmup by 5 minutes for high soreness, extends your cooldown with structured box-breathing work when HRV is suppressed, and swaps to easy endurance when aerobic efficiency is declining or workouts have felt consistently harder than expected. High training monotony triggers an endurance swap too — a genuinely different stimulus, not just a lighter version of the same thing.
A few things that stop firing too eagerly: a one-day HRV dip, RHR bump, bad night of sleep, or skin-temp/respiratory-rate spike no longer changes today's workout on its own. Single readings surface as observations (a small "Monitor" chip on the dashboard tells you what), but the scheduler only acts on patterns: 2+ consecutive days, or pattern + corroborating sustained metric. Respiratory rate is now compared against your personal baseline rather than a fixed 18 bpm floor; deep-sleep deficit fires against your personal baseline rather than a 1.5h global floor.
The dashboard got a matching redesign. Three activity rings show Readiness, Form, and Week TSS at a glance (with a track marker pointing to where your weekly progress should be by now). Below the rings, a color-accented Daily Outlook presents the AI coaching message, today's training recommendation, and any alternative — flowing seamlessly into today's planned workout in the same card. Wellness is now four quick-stat tiles (Recovery, Sleep, HRV, RHR); tap any tile to open the full Health Details sheet with every metric, every signal grouped by category, and the reasoning behind today's readiness. An always-visible Health card surfaces warning count, category dots (Recovery / Sleep / HRV / Load / Bio), and inline cards for anything that needs attention.
A new Beta Agent Log (Settings > Beta) gives you a timeline of every decision the coach makes — readiness assessments, workout selections, phase transitions, weekly plans, and post-workout analysis with full reasoning. Available for Pro and Max.
Coach+ levelled up
You can now run multiple conversations in parallel — start a new one with the +button, switch between them from the list, and each gets an AI-generated title (up to 30 are kept). Conversation starters are now context-aware, suggesting prompts based on your latest workout, upcoming race, fatigue level, or rest day. You can ask Coach+ to rebuild your weekly plan directly from chat, no need to navigate to the Training Plan page.
Coach+ pulls real numbers when you ask about analytics — fitness trends, weekly TSS history, eFTP progression, power curves, weight trend, peak benchmarks. It now reads the full unified signals report (with the actions the rules engine derived), so it can explain "today's TSS is capped at 70% with a Z3 ceiling because tsb-deep-fatigue fired" instead of guessing. It can also explain WHY you're "At Risk" or "Behind Target" with concrete numbers ("you're projected at 60 CTL but your target is 72, so you're 12 CTL short").
Other upgrades: a new command palette (Cmd+K / Ctrl+K) for instant access to every page, Coach+ chat, dark mode, and more. The coach now correctly replaces a workout when you say "swap" or "change" instead of silently adding a new one alongside. Date handling is reliable across multi-day conversations. Activities on your public profile are now clickable and link to a dedicated shareable activity page with rich preview cards on Twitter, Strava forums, and messaging apps.
Better plans and workouts
Several training plan fixes and additions:
- Taper Aggressiveness setting (Settings > Periodization > Advanced): Aggressive (~60% reduction, research-optimal), Standard (~45%, default), or Conservative (~25%).
- Taper weeks now schedule one short opener instead of two threshold sessions, the per-day TSS cap was tightened from 60% → 40% so a single Saturday ride can't dominate the week, and openers use tempo instead of full threshold.
- Intermediate A/B races now get the same Race Week / pre-race Taper TSS targets the goal does — phase derivation anchors to the nearest upcoming A/B race, so the ramp lands ahead of every race on the calendar, not only the goal.
- Expired goals now route through a 4-week maintenance plan instead of trying to project past the goal date — workouts keep generating after your A-race.
- D+1 and D+2 after any A/B race are protected as recovery (matching the symmetric pre-race taper).
- No single workout exceeds 60% of weekly TSS, even for athletes with very uneven availability.
Workout library:
- Five new Base-phase templates (Endurance + Microbursts, Tempo Pushes, Alt VO2max, Strength Blocks, Sprints) so busy athletes can hit a small intensity stimulus inside a Z2 ride/run instead of needing a separate intensity slot. Recency-aware selection rotates them so Base weeks stop cycling through the same three workouts.
- Swimming workouts rebuilt to match expert swim-coach prescriptions: classic CSS 100m repeats with 35s rest, cleaner pull and endurance set structures.
- Heart-rate-based cycling workouts if you ride outdoors without a power meter (Settings > Training).
- Power-based running targets for Stryd and Garmin running power meter users.
- Over-under workouts correctly straddle FTP at 95% / 105% (locked so TSS adjustments can't distort them).
- Post-workout analysis sees the full back half of long rides — up to 30 fully-itemised intervals plus bucketed totals beyond.
eFTP projection on Analytics
Your eFTP history chart now continues into the future as a dashed line with a widening "weather-plume" band — projected forward along your planned CTL trajectory using a per-athlete regression fit to up to a year of weekly snapshots. Requires at least 8 weeks of data and the band widens with horizon to honestly reflect uncertainty. Directional guidance, not a promise — actual FTP gains also depend on training specificity, not just volume.
Also new
- Wellness check-in in the daily briefing — rate stress and motivation with one tap.
- Chronic stress detection (HRV both suppressed and unusually stable — a pattern standard metrics miss).
- HRV stability trend in the daily coaching note (improving / worsening week-over-week).
- Mobile Sessions in Account settings — see and revoke iOS app sessions.
- Metric / Imperial unit preference, applied consistently across the app and all email types.
- Two new blog posts: The Science Behind IntervalCoach and HRV-CV: What Volatility Tells You That HRV Alone Does Not.
These are just the highlights. See all 250+ changes in the full changelog.
More coming soon. Questions or ideas? Just reply to this email.