Stress shows how far your heart rate ran above your usual resting heart rate, and your HRV below your usual HRV, while you were awake and outside a workout. It runs from 0 to 100. Time at or calmer than your usual reads 0, and higher numbers mean more estimated physiological strain. The day score is the average since midnight.
01How each 5 minutes is scored
Titan splits the day into 5-minute blocks. For each block, it divides your average heart rate by your usual resting heart rate. When your watch recorded HRV in that block, Titan also divides your usual HRV by the block's average HRV and averages the two ratios. Stress is how far the result sits above 1, times 100, kept between 0 and 100.
| Block | Usual | Block reading | Stress |
|---|---|---|---|
| Heart rate only | 55 bpm resting | 72 bpm | 31 |
| With an HRV reading | 55 bpm, 50 ms | 72 bpm, 40 ms | 28 |
In the first row, 72 divided by 55 is 1.31, which gives 31. In the second, 50 divided by 40 is 1.25. The average of 1.31 and 1.25 is 1.28, which gives 28.
A block with no heart rate reading is a gap. Titan never counts a gap as zero.
02What counts toward the day score
The day score is the time-weighted average of your waking blocks since midnight. Blocks inside sleep count as sleep stress instead. Blocks inside a workout are drawn on the chart but left out of the score.
A walk, stairs or chores outside a workout raise your heart rate, so they read as stress. Start a workout on your watch to leave that time out.
The word under the score names its level.
| Score | Level |
|---|---|
| 0 to 25 | Low |
| 26 to 50 | Moderate |
| 51 to 75 | Elevated |
| 76 to 100 | High |
03Your usual resting heart rate and HRV
Your usual resting heart rate is the median of Apple Health's daily resting heart rate over the last 60 days. Your usual HRV is the median of your daily average HRV over the same 60 days. Each needs readings on at least 36 of those days. The window is fixed. No setting changes it, and it does not follow the Recovery window. Until both baselines exist, there is no Stress score. See personal baselines.
04The Stress screen
Tap the Stress card on Today to open the Stress screen. The ring shows the day score and its level. The Today card shows the same score with a line of your last 7 day scores.
The day chart
The chart runs from last night's bedtime to now, or to midnight for a past day. The line is grey while Low, a lighter grey while Moderate, and red above 50. Thin lines across the chart sit at 25 and 50. A shaded band marks sleep and a faint band marks each workout. The dot is your latest reading. Tap the chart to read a block's stress and heart rate. A break in the line means no heart rate reading.
Time at each level
Each row shows the share of your waking time outside workouts at that level, and how long it lasted. High covers everything above 50, so it includes Elevated. The total next to the heading counts only time with a heart rate reading.
Sleep and workouts
Each row shows the average stress across that sleep or workout. Neither counts toward the day score. A workout usually reads high, as you would expect.
Stress history
The history has a 7 Days, 30 Days and 60 Days picker and one bar per day. The trend table below compares your 7-day rolling average today with the same average 3, 7, 14, 30 and 90 days earlier. Lower stress shows as an improvement.
When there's no score
"No waking heart rate yet today" means your watch has not recorded heart rate since midnight outside sleep and workouts. The score starts once it does. "Needs more days of heart rate and HRV for a baseline" means Titan does not yet have 36 days of both in the last 60. Check that Titan can read Heart Rate, Resting Heart Rate and Heart Rate Variability in Apple Health, and keep your watch on.
05Stress alerts
Titan can send a notification when your Stress score reaches a level you choose. Tap your avatar on Today, then the bell on You.
- Turn on Allow Notifications.
- Turn on Stress Alert. It is off by default.
- Set Stress Alert Level with the minus and plus buttons. It moves in steps of 1 from 0 to 100 and defaults to 75.
The alert fires when your day score is at or above the level. Titan skips it for 30 minutes after a workout ends and sends at most one Stress alert per hour. The message reads "Stress is elevated at" followed by your score. The day score is an average since midnight, so it moves slowly. Lower the level for earlier warnings. For a routine to act on those alerts, see managing recovery and stress and notifications.
