Energy pacing

Who it is for#

The mode is written for people whose symptoms can get worse after too much effort, often hours or days later (in ME/CFS this is called post-exertional malaise). For them the usual fitness defaults pull the wrong way: a steps goal, missions that pay for movement and a coach that says "train". NICE guideline NG206 (2021) took graded exercise therapy out of its advice for ME/CFS and puts energy management first: staying within the person's own limits. Pacing with a heart-rate limit is one way people do that.

What the mode does:

• It shows your measured heart rate against a ceiling you choose.
• It counts the minutes of your day above that ceiling.
• It turns the day to rest after you went over, after a crash you report, or when your HRV stays low.
• It takes out the parts of the app that ask for more movement.

What it does not do: it does not diagnose anything, it does not tell you which ceiling is right, and it cannot warn you in real time. Data reach us after a sync, so for an instant alert use the high heart-rate alert of the watch itself. On some watches that alert only watches after a while without movement, so check the watch's manual.

With POTS heart-rate pacing often does not work, because the pulse can pass the ceiling just from standing up or light activity (German ME/CFS Society). Agree with your doctor whether a ceiling makes sense for you. The same applies to any heart condition or medicine that changes your pulse.

Switching it on#

Open Settings, section "Goals" ("Cíle"), card "Energy pacing" ("Šetření energií"). The card says: "For people who need to pace their energy (for example chronic fatigue syndrome ME/CFS, long COVID, or POTS, where the heart rate jumps when you stand up)." Then:

1. Type a ceiling in "Heart-rate ceiling (60 to 180 bpm)" ("Hranice tepu (60 až 180 tepů/min)"), or take the suggestion (see below).
2. Press the switch "Turn on energy pacing mode" ("Zapnout režim Šetření energií"). Without a ceiling it will not turn on: "Enter a heart-rate ceiling first; the mode cannot be turned on without one."
3. The card answers "Energy pacing mode is on", and the tab bar renames Performance to "Body reserve" at once.

"Save ceiling" ("Uložit hranici") changes the ceiling later. With the mode off it says "Ceiling saved. The mode is still off." Turning the mode off keeps the ceiling for next time: "Energy pacing mode is off. We keep your ceiling; the step goal, movement missions and biological age come back."

Saving the ceiling needs the consent to health data that the app asks for, because a heart-rate limit kept for a condition is health data. Only the account itself can change the mode, not a paired device.

If your device does not send heart rate minute by minute, the card says so: "Your device does not send us heart rate by the minute, so we cannot count the minutes above your ceiling. The rest of the mode (with no push to move) works."

The heart-rate ceiling#

The ceiling is a whole number of beats per minute from 60 to 180. The range is wide enough for a resting rate of 45 plus 15, and narrow enough that a typo (15, 1150) is refused: "Please enter a heart-rate limit from 60 to 180 bpm."

Your own number comes first. Best from your doctor, or from an exercise test if you have had one. The card says: "The suggestion from resting heart rate + 15 is a rule of thumb from practice, not a measurement, and its evidence is thin."

The suggestion: resting rate plus 15#

"Suggest from resting heart rate" ("Navrhnout z klidového tepu") offers the rule used in practice: the mean resting heart rate of the last 7 days (today included) plus 15 beats. It needs resting rates from at least 4 of those 7 days, otherwise the button is not offered. A day without a reading does not count as a zero.

The rule is widely used and thinly supported. A survey of 488 people with ME who pace with a heart-rate monitor (Clague-Baker and colleagues, 2023) found one earlier study of it and asked for more research. So we offer it as a starting point and never set it for you. If the suggestion falls outside 60 to 180, it is not offered.

When you took the suggestion and your resting rate later moves, the card offers a new one once today's suggestion is 5 beats or more away from your ceiling: "Your resting heart rate from 5 nights of the last 7 days is 58; the suggested ceiling is now 73 instead of 66 bpm." If the new suggestion is higher, it adds: "A higher resting rate can also mean an illness or a worse stretch, so raise the ceiling with care." It is only offered, never applied. A ceiling you typed yourself is never compared.

The chart and the three bands#

The Health tab card "Heart rate through the day" draws the day against your ceiling in three bands. A caution band of 10 beats sits under the ceiling, so the line is not the first warning.

The example is a ceiling of 115. A pulse of exactly 115 is still "Careful", 116 is "Over". Heart-rate zones and the stress bars are replaced by these bands (see Heart-rate zones).

Under the chart one line says how the day went, for example "Over the ceiling 34 min of 612 min measured · longest stretch 20 min · highest heart rate 131", or, when nothing was over: "All measured time under the ceiling of 115, 640 min measured · highest heart rate 108". For a day still running it reads "So far all measured time under the ceiling of 115".

• Minutes over are the minutes with a reading above the ceiling.
• Minutes measured are the minutes with any reading. They are shown beside the count so an hour off the wrist is not read as calm.
• Longest stretch is the longest run of 5-minute slots whose average is above the ceiling. A string of single high minutes among calmer ones counts in "minutes over" but not here.
• Highest heart rate is the day's peak.

A day with no minute-by-minute heart rate gets no minute counts, and the card says so: "We have no minutes over the ceiling for this day: no minute-by-minute heart rate reached us for it." The chart keeps its line, but no number is made up.

What makes the day a day of rest#

The mode caps every day at "PACE" ("ŠETRNĚ", the pacing form of the easy day) and turns it to rest in four cases. The day's verb on the Overview (see Daily coach) is the lowest of them.

A day over the ceiling in the last two days#

If yesterday or the day before ended with more than 5 minutes above the ceiling, today is rest. The worsening after overexertion often comes with a delay of hours or days (NICE NG206), so a day over speaks again the day after next. The banner names the days: "34 minutes above your ceiling of 115 yesterday and 12 the day before." followed by "A crash after a day above it can come hours or days later, so make today mostly rest."

• Each day is judged against the ceiling that was in force on that day. If you lowered it during the day, the lower one applies, because lowering it is the safer direction. Raising it in the evening does not re-judge the hours already lived.
• A day that is not closed yet is read as it stands. The coach speaks in the morning, and later data can still move the count.
• A day with too little recorded still counts here when the minutes above the ceiling were measured, because minutes measured above the ceiling happened however little else was seen. A day without minute-by-minute heart rate says nothing.

HRV held under the band it had before it dropped#

The usual HRV band follows you: it is built from the last 60 days, so a drop that lasts is slowly taken in as the new normal. For an athlete that is right, because the body adapted. With a chronic illness a new low is not a healthy baseline. So in this mode, once your 7-day HRV (at least 3 nights in the week) falls under the band, the band is held where it was the day before, and the week is measured against it until it climbs back into it. Only overnight HRV counts.

The resting rate sits beside it: the 7-day mean against the 28 days before the drop (at least 14 days with a reading), and it counts as raised when it is more than half a spread of your single days higher and more than 2 bpm higher. A raised resting rate with low HRV means the body works harder at rest, and the day is rest. Low HRV alone keeps the gentle day, and the banner ends "Take more rest today."

The full banner reads, for example: "Since 12 Oct your 7-day HRV has been below its band from before the drop: now 38 ms, before around 52 ms. Your resting heart rate is 63 bpm against 58 before. Your body is working harder. Make today mostly rest." After 14 days it adds "even if this can look like a new normal". A held band can last up to about eleven months.

A crash you report#

See the next section. A reported crash makes today rest, whatever the numbers read.

What the body itself says#

A night with no restorative sleep, a Body Status of Alert or a low readiness gives rest on its own, as it does outside the mode.

A crash is not an illness#

In ME/CFS a crash is the expected cost of overexertion, not an infection. So the mode has its own answer.

• Where to say it. Under the verdict, next to "Fine", "Tired" and "Ill", the mode adds a fourth answer: "Crash" ("Propad"). The full daily check-in has a box "A crash today" ("Propad dnes") with the help "A worsening after overexertion, which can come with a delay. The day then turns to rest and does not count as an illness."
• What it does. Today becomes rest: "You report a crash today, so rest. Do not catch up, even if the afternoon feels better."
• Tomorrow too. Recovery from a crash can last hours, days or weeks (NICE NG206), so a crash reported for yesterday keeps today at rest: "You reported a crash yesterday. Recovery can take longer, so today is mainly rest as well." It is carried only while today's check-in has no answer. If you save "no crash" today, that is your word that it has passed.
• Not an illness. A crash does not turn the day into an illness day and does not print "see a doctor" over it.
• The safety line. A crash and an infection can coexist. When Body Alert is elevated (above 55) beside a crash you report today, the crash stays the headline and keeps the sentence "If a fever or other new symptoms appear, see a doctor." When Body Alert is high (above 70), the Body Alert banner stays the headline.
• Ill and a crash together. If you also report feeling unwell, the Body Status keeps its own sentence about that.

"Ill" is for an infection or another sickness. "Crash" is for your pacing. They do not replace each other.

What changes in the app#

The calculation of Body Status, recovery and sleep does not change. What changes is the words and the surfaces that ask for movement.

• Performance tab becomes "Body reserve" ("Rezerva těla"). It is the same number as Training Readiness, named for a body that is not training: ring "reserve", card "What drives the reserve", "Reserve outlook", "Reserve-based guidance". The training cards, the fitness and fatigue curve, adaptation and the Training card are hidden (see Recovery and readiness). The tab is part of Premium.
• Coach. No session, no button, no picker. The verb is "PACE" or "REST" and the tip names your ceiling: "Split activities up and rest in between. Keep your heart rate under 115." The reason for a hard recent stretch reads "The last few days asked more of you than usual, so save your strength today." The training plan is paused (see Training plan).
• No step goal, no active-minutes goal. The card says "In energy pacing mode we do not set a step goal." The sleep goal stays.
• No biological age anywhere (Health tab, Overview, weekly digest e-mail), because steps, active minutes and fitness count in it.
• No Load & Recovery card on the Overview and no load ratio, load gauges, heart-rate zones, activity trend, Intensity minutes or Active Zone Minutes on the Activities tab. The session list and the counts stay (see Activities).
• Stress is called "body load" ("zátěž těla"), because the pulse can jump with no mental stress behind it, for example on standing up.
• Energy map. No peak chip and no highlighted training window. Only training blocks you set yourself are drawn (see Morning energy).
• Advice. The wordings that send you to walk, move or train are left out, including after an illness: "After an illness, return to everyday activities slowly and within your limits: keep your heart rate under your ceiling and put rest between activities." The day's outlook reads "Recovery after overexertion can take hours, days or longer, so let how you feel set the pace."
• Progress. The check-in streak tile and the "Streak continues" line are hidden (a day of rest must not read as a broken run), and there is no steps mission and no steps badges.
• Weekly report. Steps by day, WHO minutes and training balance give way to a card "Days within limits" (see Notifications).

Missions and badges#

On the Progress tab the mode has its own mission instead of the steps one: "A day within limits" ("Den v mezích"), worth 15 XP. A day is within limits when it had at most 5 minutes above the ceiling on a day with heart rate recorded for at least 12 hours. The card says: "At most 5 min above 115 bpm · settled after the day".

• The day is settled after it ends, once the finished day has synced, so not necessarily the next morning.
• A day with too little recorded counts neither way. It is not met and it is not failed.
• A day over the ceiling takes nothing away. Each day stands alone, there is no run of days that breaks.
• The mission is judged against the ceiling that was in force that day. The day counts for the mission once the app has drawn your day with the mode on.

The badge family "Weeks within limits" ("Týdny v mezích") counts calendar weeks (Monday to Sunday) with at least 5 days within limits, for 1, 4 and 12 weeks. It shows only when your device records heart rate by the minute. The "perfect week" badge asks, in this mode, for data, a check-in and a day within limits every day, instead of a high readiness. Tiers you already earned stay.

Weekly report: "Days within limits" shows each day as "within limits", "34 min above the ceiling" or "unknown", and the summary "Within limits on 5 of 6 days with enough heart rate recorded. Ceiling 115 bpm."

Free and Premium#

The mode, the ceiling, the banners about minutes over, a crash or HRV, and the heart chart against your ceiling are free. On the free plan the narrow Overview still draws the chart against your ceiling and keeps these banners. The "Body reserve" tab, like the Performance tab it replaces, is part of Premium.

Frequently asked questions#

Which ceiling should I choose?#

The one your doctor gives you, or one from an exercise test. If you have neither, the suggestion of resting rate plus 15 is a starting point with thin evidence, and you can change it any time. Do not set it by what you want to be able to do.

Why is today "rest" when I feel fine?#

Because yesterday or the day before ended with more than 5 minutes above your ceiling, you reported a crash, or your 7-day HRV is still below the band it had before it dropped with a raised resting rate. The worsening after overexertion often comes with a delay of hours or days, so the rest is for the day after next too. The banner on the Overview names the reason with the numbers.

Why does it say "unknown" for some days in the report?#

Because the day had less than 12 hours of heart rate recorded, or no minute-by-minute heart rate at all. We say "unknown" instead of guessing.

Can I switch the mode off and keep my history?#

Yes. Switching off keeps your ceiling. The step goal, movement missions and biological age come back, and nothing you recorded is lost.

Will the app warn me when I go over the ceiling?#

No, not in real time. Data reach us after a sync. Set the high heart-rate alert on the watch itself.

Does the mode treat or diagnose ME/CFS, long covid or POTS?#

No. It shows measured heart rate against a number you choose, and it removes prompts to move more. It is not a medical device or a treatment. Agree on your ceiling and your pacing with your doctor, and see a doctor if you get a fever or new symptoms.