WORKOUT TIMERS

Running interval timer

Hard and easy segments by time, cues in your ears and heart rate on your wrist

Running intervals alternate faster segments with easy jogging or walking. Timing them, rather than measuring distance, works anywhere: on the road, on trails or on a treadmill.

Running interval sessions
SessionHardEasyRounds
Run-walk1 min run2 min walk8
4×4 14 min3 min4
30/3030 s fast30 s jog10 to 20
Pyramid1, 2, 3, 2, 1 minEqual to the hard part1

Key study

Four 4-minute intervals beat steady running for fitness

  • Randomized trial
  • 40 healthy men
  • 8 weeks

Running 4 minutes at 90 to 95% of maximum heart rate, with 3 minutes of easy jogging between, four times, improved VO2max more than long slow running or threshold running.

Source 1

How to set it up in Cero

  1. Create a new simple timer with your hard time, easy time and rounds.
  2. Add a warm-up and a cool down.
  3. Turn on voice cues, so you hear every change through your headphones.
  4. Take it on your Apple Watch, and follow your heart rate as you run.
  5. For pyramids, build each step as its own interval in the advanced timer.

With Adaptive HR, Cero can warn you during a hard interval if your heart rate is below or above your target, and extend the easy part until you’ve recovered.

Free toolTry a running interval timerSet your intervals in the browser, free.

Sources

  1. Helgerud J, Høydal K, Wang E, et al. Aerobic High-Intensity Intervals Improve VO2max More Than Moderate Training. Med Sci Sports Exerc. 2007;39(4):665-671. doi.org/10.1249/mss.0b013e3180304570

YOUR NEXT SESSION STARTS HERE

Bring the effort.
We’ll keep the time.

Cero is free to download for iPhone, iPad and Apple Watch.

Download Cero
Cero’s simple timer on iPhone 18 Pro, with the green wave about half full during a high-intensity interval

Cero is a timer, not a medical device. If you’re new to hard exercise, are pregnant or have a health condition, check with your doctor first, and stop if you feel unwell.