Japanese Walking Explained: The Real Research Behind Interval Walking Training (and How to Track It)

Somewhere in the last year, "Japanese walking" went from a niche exercise-physiology protocol to a trend showing up on CNN, WebMD, and half of Instagram's fitness accounts - usually with a claim that it beats a flat 10,000-step goal. The method actually has a formal name researchers gave it years ago: Interval Walking Training, or IWT, and it comes with two real published studies behind it, not just a viral demo video. Here's what those studies actually measured, the protocol as it was originally designed, and how to run it on an iPhone or Apple Watch without a stopwatch in your hand.

What is Japanese walking, actually?

Interval Walking Training alternates a brisk-paced interval with an easy-paced interval, back and forth, for about 30 minutes. It picked up the "Japanese walking" nickname online because it was developed in Japan, but the substance is simpler than the trend name suggests: it's a change of pace on an ordinary walk, not a new piece of equipment or a running workout. The bigger difference from most walking advice is what it's built around. A goal like 10,000 steps a day is a volume target - how much you moved. IWT is an intensity target - how hard you moved during part of the walk. Those are different questions, and a session can be short on steps while still hitting the protocol correctly.

The two real studies behind it

The protocol comes out of the Shinshu University Graduate School of Medicine in Nagano, Japan, from exercise physiologists Hiroshi Nose and Shizue Masuki. In the original 2007 study, published in Mayo Clinic Proceedings, 246 middle-aged and older adults either did interval walking or walked continuously at a moderate pace over roughly five months. The interval group came out with larger gains in peak aerobic capacity and a bigger drop in resting blood pressure than the steady-pace group, despite covering similar overall distance.

A larger follow-up, also in Mayo Clinic Proceedings (2019), tracked 679 adults with an average age of 65 over another five-month period, specifically to see how much high-intensity walking time actually mattered. The amount of brisk-interval time each person logged in a week turned out to be the strongest predictor of how much their fitness and health markers improved - and most of that benefit was already captured by around 50 minutes of brisk walking spread across the week, not by hitting the intensity on every single outing. That's the version of "Japanese walking" worth trusting: two named, peer-reviewed studies from the same lab, not a single viral claim.

The exact protocol: three minutes fast, three minutes slow, five times

The structure researchers used is straightforward enough to run without any special gear. Walk briskly for 3 minutes, then drop to an easy pace for 3 minutes, and repeat that cycle five times - 30 minutes total, with a short easy warm-up and cool-down on either end if you want one. The original study design asked participants to aim for four or more sessions a week, though the 2019 follow-up found weekly high-intensity minutes mattered more than hitting a specific number of sessions. There's no required course or incline - a sidewalk, a treadmill, or a loop around a park all work the same way.

What "fast" and "slow" should actually feel like

You don't need a lab to find the right effort. The simplest gauge is the talk test: during the brisk 3 minutes, you should be working hard enough that a full sentence is a struggle - short phrases only. During the easy 3 minutes, you should be able to hold an ordinary conversation without catching your breath. If you'd rather check a number instead of a feeling, Stepzy's heart rate zone calculator gives you personalized zones from your age and resting heart rate: the brisk intervals should land you around your cardio zone, and the easy intervals should drop you back toward light or fat-burn. Stepzy's own heart rate zones view shows where a finished workout actually landed, which is a better check than guessing after the fact.

Steps and calories: the wrong number to chase

Neither of the studies behind this method measured steps or calories as the outcome - they measured aerobic capacity and blood pressure. So there isn't a verified "X calories per session" figure to hand you, and most numbers floating around online for this specific workout aren't sourced to anything checkable. What's true in general is that pushing part of a walk well above a steady stroll burns more than the same 30 minutes at one flat pace - but exactly how much more depends on your weight, your actual pace during the fast intervals, and the terrain, more than any generic chart can tell you. If you want your own estimate, Stepzy's steps-to-calories tool uses your own body weight rather than a one-size table. Your step count for the session still adds up normally either way - it's just not the number this particular method is built around.

Japanese walking vs. 12-3-30 vs. Zone 2 walking

Structured walking has produced a few distinct trends, and they're not interchangeable. The 12-3-30 workout holds a single elevated effort for a full 30 minutes on a steep incline - Zone 2 walking asks you to stay at one deliberately low, sustainable effort the whole time, building your aerobic base without ever getting out of breath. Interval walking training sits between them by design: it's the only one of the three where the effort level itself keeps changing, which is exactly the mechanism the Mayo Clinic Proceedings studies tie to the bigger fitness and blood-pressure gains over steady-pace walking at a matched average speed. None of the three is strictly "better" - they train different things, and rotating between them is a reasonable way to avoid a routine going stale.

Tracking intervals on your iPhone or Apple Watch

Start a regular outdoor walk workout on your Apple Watch (or iPhone) before your first fast interval, the same as you would for any tracked walk - Stepzy doesn't need anything special from you beyond that. During the session, a simple phone timer or even the Watch's own interval alerts can cue the 3-minute switches; there's no dedicated interval mode to hunt for, and the talk test works fine on its own if you'd rather not watch a clock. Once the workout ends, Stepzy reads it straight from Apple Health like any other session: the route and pace show up on the GPS workout map, the full entry lands in your Workouts tab with duration and heart rate intact, and AI Coach can read the pace swings across the session and summarize the effort in plain language afterward - a faster way to see whether your "fast" intervals were actually fast than eyeballing a pace number mid-walk.

Getting started: frequency, and who should ease in

You don't need to jump straight to five full cycles. Start with two or three rounds instead of five, keep the "fast" interval closer to brisk than all-out, and add a round every week or two as it starts to feel manageable - the original protocol's four-sessions-a-week target is a goal to build toward, not a starting point. If you're new to structured exercise, pregnant, or managing a heart or joint condition, treat this the way you would any new higher-intensity activity and check with a doctor before pushing the fast intervals hard; see Stepzy's guide for beginners for a gentler starting point either way. And if a couple of interval sessions a week means your step count looks uneven compared to your usual daily walks, Stepzy's adaptive goal engine adjusts your target from your real baseline instead of treating a lower-step, higher-effort day as a miss.

The short version: "Japanese walking" is a real, specifically defined protocol - three minutes brisk, three minutes easy, five times through - with two named studies out of Shinshu University behind it, not just a wellness-trend name. It's worth trying on its own merits, but it's not a replacement for whatever step goal already works for you; it's a different question about intensity, not distance. Whatever pace you actually walk, Stepzy reads it straight from Apple Health and logs the session honestly either way.