Why 90 minutes
Sleep researcher Nathaniel Kleitman proposed that the body runs on roughly 90-minute cycles during the day as well as at night. The idea has been popularised as a way to plan work: one deep block that lasts about an hour and a half, followed by real recovery.
The science behind daytime cycles is less settled than the advice suggests, but the format works well in practice for tasks that take a long time to get into, such as writing, research or complex code.
The long break is not optional. Twenty minutes away from the task lets you return with fresh eyes, and it is often during the break, while walking or making tea, that a stuck problem quietly resolves itself. If you only manage one 90-minute block a day, put it where your energy is highest and protect it like a meeting.
Planning a day around 90-minute blocks
- Two or three blocks a day is a realistic ceiling for most people.
- Put the hardest task in the first block, before messages and meetings start.
- Spend the 20-minute break moving or resting, away from screens if you can.
How to use it
- Press Start. The 90-minute countdown runs in the ring, and a soft chime marks the end.
- Add sound from the Mix or Sounds tab. A steady background such as rain or brown noise makes it easier to stay in the session.
- Open focus mode (the expand button, or press V) for a large, distraction-free countdown that keeps the screen awake.
- Change any length in the timer settings; the next session uses it.
Questions
- Is 90 minutes too long to concentrate?
- It can be at first. Build up from 50-minute sessions, and allow yourself a short pause inside the block if you need it.
- What sound helps with long sessions?
- Steady, low-detail sound is easiest to listen to for a long time: brown noise, steady rain or a distant café.
- Will the timer keep time if I switch tabs or lock my phone?
- Yes. The timer counts against the real clock rather than ticking in the background, so it stays accurate when the tab is hidden or the screen is off. Turn on notifications in the timer settings to be told when a session ends.
- Does the timer work offline?
- Yes. Once Focuship has loaded, or is installed to your home screen, the timer, the chime and the generated noises all work without a connection.