Productivity methods
52/17 and 90-minute rhythms, checked.
Two popular ideas about how long to work before a break, where their numbers come from, and how to use them sensibly.
· 3 min read · 5 steps
- 52/17 from
- DeskTime app data, 2014
- 90 minutes from
- Kleitman's sleep research
- Evidence
- Observations, not rules
- Best for
- Finding your own rhythm
What it is and where it began.
The 52/17 rule says to work for 52 minutes and then take a 17-minute break. It comes from DeskTime, a time-tracking company, which reported in 2014 that the 10% of its users it rated most productive worked about 52 minutes at a time and then took about 17 minutes off [1].
It is an observation from one company's own app data, not a controlled study, and it does not show that the rhythm caused the productivity. DeskTime's own later looks at its data found other patterns, including 112 minutes of work and 26 of rest in 2021 [1]. The useful lesson is that the most productive people took real breaks.
The 90-minute idea comes from sleep research. Nathaniel Kleitman proposed a basic rest-activity cycle of roughly 90 minutes that might continue through the day [2]. Evidence for such a cycle while awake is mixed [3], so "work in 90-minute sprints" is a popular extension of the idea rather than an established finding.
How to do it, step by step.
Pick a starting rhythm
Try 50 minutes of work and a 10-minute break, close to 52/17, or 90 and 20 for deep work.
Work on one task per session
As with any timer method, one task at a time.
Take a real break
Move, look away from the screen, get some air. Scrolling on your phone is not much of a break.
Notice when focus actually fades
Watch for drifting attention before the timer ends, or energy left when it rings.
Adjust after a week
Shorten or lengthen the rhythm to fit what you noticed, instead of following a number from someone else's data.
Who it suits, and its limits.
It suits you if
- You want longer stretches of focus than 25 minutes.
- You work on demanding tasks that take time to get into.
- You like experimenting and keeping notes on what works.
Where it falls short
- The 52/17 figure is a vendor's observation, not a peer-reviewed result, and the company's later data gave different numbers.
- A 90-minute daytime cycle is not well established, and people differ a lot.
- Long blocks are hard to fit into a day full of meetings.
Common mistakes to avoid.
Treating 52 or 90 as magic
The numbers come from limited data. Use them as a starting point and adjust.
Skipping the break
The one consistent message is that breaks matter. A 52-minute session without the 17 is just a long session.
Breaks on the phone
A break spent on email or social media rarely restores attention. Step away.
Forcing long blocks on short tasks
Small tasks do not need 90 minutes. Use long blocks for deep work only.
How to do it in thisflow.
Each step uses a feature that is in the app today.
Deep work, 50/10
The Deep work rhythm runs 50 minutes and a 10-minute break, close to 52/17. Add five minutes with +5 min when you need them.
Ultradian, 90/20
The 90/20 rhythm gives one long session and a 20-minute break, for the deepest work of the day.
Or let it count up
Flowtime counts up and suggests a break that fits the time worked, if you want to find your own rhythm.
Protect the time
Drag the task into the calendar and stretch it to 90 minutes, so the block is not split by a meeting.
Questions and answers.
Is the 52/17 rule scientifically proven?
No. It comes from DeskTime's 2014 analysis of its own users, not a controlled study. The company's later data showed other patterns, such as 112 minutes of work and 26 of rest.
What are ultradian rhythms?
Biological cycles shorter than a day. Kleitman proposed a roughly 90-minute rest-activity cycle, best documented in sleep; evidence for it during the day is mixed.
Does thisflow have a 52/17 timer?
Not as a preset. The closest is Deep work, 50 minutes and a 10-minute break, and +5 min adds time to a running session.
Which rhythm should I choose?
Start with one, keep notes for a week, and adjust. The right rhythm depends on you and the work, more than on any single study.
Sources
Numbers in the text, like [1], point to these sources.
- [1]DeskTime: Does the 52-17 rule really hold up?desktime.com/blog/52-17-updated/
- [2]Kleitman (1982): Basic rest-activity cycle, 22 years later. Sleep 5(4)pubmed.ncbi.nlm.nih.gov/6819628/
- [3]Wikipedia: Basic rest-activity cycleen.wikipedia.org/wiki/Basic_rest%E2%80%93activity_cycle
More methods to try.
Pomodoro technique
Short, timed rounds of focus on one task, with a break after each.
Time blocking
Give each task a slot in your calendar, so the day has a plan.
Eisenhower matrix
Sort tasks by urgent and important, and treat each of the four boxes differently.
Find your rhythm, then keep it.
Free during the beta. Pomodoro, Deep work, 90/20 and Flowtime in one timer.