Field note
A training streak counts weeks that hold at least one recorded session. It is a record of showing up, not a claim about how fit you are.
Forty weeks of one gentle walk each is a real attendance record and says nothing about fitness on its own. The reads that speak about your body are elsewhere.
This week is the plain sum of sessions recorded since your week began, with their total time, distance, and climb. Your week starts on the day your phone says it does, Monday in most of Europe and Sunday in the United States, because that is the week you already live in. A session in progress is not counted until it is finished.
Weeks in a row counts weeks with at least one recorded session. Not two, not a minimum length. Any higher threshold invents a rule about what deserves to count as training, and a short walk on a hard week is exactly the kind of thing a streak should be able to hold.
| Read | Plain meaning |
|---|---|
| This week | Sessions finished since your phone's week began |
| Weeks in a row | Consecutive weeks with at least one recorded session |
| Best so far | Longest run inside the history the app can see |
The week you are in is still being lived, so it can only ever add. Without that, the number would fall to zero every Sunday midnight and read as a punishment for the calendar turning over. Best so far is not a lifetime record if the history only goes back about a year of recorded sessions.
How hard a finished session felt is a different question. That lives in What is workout effort? How much whole-day motion adds up lives in How much daily movement matters?
Michie and colleagues (2009) and Harkin and colleagues (2016) find that self-monitoring, especially paired with a goal and feedback on progress, is among the more reliable ingredients in interventions that move physical activity. Counting your weeks back to you is that ingredient and nothing more.
The research is about the act of monitoring your own progress. It is not evidence that a large streak makes you fitter. Compernolle and colleagues (2019) reach a similar conclusion for sedentary-behavior interventions that use self-monitoring: the effect belongs to the counting habit, not to a magic number on a tile.
Engagement features tend to work while they are running and fade when they stop. Patel and colleagues (2019), in the STEP UP trial, found a twenty-four-week gamified step programme with social support raised daily steps by roughly six hundred to nine hundred over control. In the twelve weeks after it ended, activity fell in every arm. Only one of the three designs still beat the control group. A number on a tile is a nudge, not a training effect.
The known failure of streaks is what happens when one breaks. Marlatt and Gordon (1985) describe how, after a slip, the harsh explanation people give themselves is what turns one missed day into abandoning the whole thing. That work is about substance use, not exercise apps, so treat it as a warning rather than a finding about training. It is still the reason an honest streak never draws a missed day in red, never announces a broken run, and never counts down to one.
An app can only count what reached the phone. A session your watch missed, a ride you forgot to start, a week of hard physical work with nothing recorded: all of that is invisible, and none of it means you did nothing. This is a record of recordings. Heart-rate load against your recent base is a separate read in What is cardio load?
I write these because I build Aera, an iPhone app that reads Apple Health against your own baseline and puts the research and the error bars underneath every number it shows you, including this one. You do not need it to use anything above.