TANAKA’S SLOW RUNNING: RUN SLOW TO RUN BETTER
What if, to improve as a runner, you had to learn to run slower? Slow jogging developed by the Japanese physiologist Hiroaki Tanaka proposes a simple training method: running at a very low intensity, almost at a brisk-walk pace, while maintaining a comfortable level of effort. An interesting strategy for both starting out in running and improving the aerobic base, accumulating minutes of activity, or performing recovery runs.
What is slow running?
Slow jogging or slow running is a form of low-intensity running popularized by the Japanese researcher Hiroaki Tanaka, professor at Fukuoka University. Its principle is simple: run slowly enough to be able to hold a conversation and even smile while you run.
Tanaka popularized the Japanese concept “niko niko”, which can be translated as “smile.” The idea is to use the smile and the ability to speak comfortably as practical signals that we are running at an appropriate intensity.
An article from Natural Running Center captures this philosophy precisely: If you can’t smile, speak easily, or even sing, you’re probably running too fast. (Natural Running Center)
It isn’t about setting a universal speed. The roughly 6-7 km/h often associated with the method are just a reference: for some people it will be a very easy jog and for others it might be even slower. The important thing is the relative intensity and the sense of comfort.
The Smile Test
Here is a very simple way to know if you’re doing slow running:
Can you run and maintain a conversation without running out of breath? Can you smile naturally?
If the answer is yes, you’re probably at an appropriate intensity.
If you’re watching the clock, gasping, or needing to concentrate to keep the pace, slow down.
And this concept has a small but interesting scientific backing. A study conducted with 24 trained runners found that smiling while running was associated with lower oxygen consumption and better running economy compared to frowning or a control condition. The authors proposed that smiling periodically could be used as an attentional cue to promote movement economy. (ScienceDirect)
It doesn’t mean that smiling will make you a better runner by itself, but it fits perfectly with Tanaka’s philosophy: relaxation, comfort, and absence of unnecessary tension.
How do you do it?
1. Start much slower than you think.
First forget about pace per kilometer.
2. Seek the “smile pace.”
You should be able to talk easily and maintain a sense of control.
3. Slightly shorten your stride.
The goal is to run lightly, relaxed, and without trying to move forward with large strides.
4. Keep your body relaxed.
Avoid tensing shoulders, arms, or jaw. The feeling should be of easy, fluid movement.
5. Walk when necessary.
For a beginner, alternating easy running and walking is perfectly valid.
6. Increase time first, then speed.
The priority is to build exercise tolerance, not to prove how much you can run on day one.
Should you run on your forefoot?
Here it’s useful to separate Tanaka’s philosophy from what science actually says.
The title of Tanaka’s book references “Run with Smile, Midfoot Strike”, and the slow jogging approach promotes light running with a soft landing of the foot. (Natural Running Center)
However, I would not recommend forcing a midfoot strike in the belief that it will prevent injuries.
Most long-distance runners land on the heel or rearfoot. A systematic review and meta-analysis found that around the 79% of distance runners initially landed on the rearfoot, a figure rising to 86% as distance increases. Moreover, the available evidence does not conclusively show that midfoot or forefoot striking provides a performance advantage. (PubMed Central (PMC))
Another review concluded that deliberately shifting from rearfoot to midfoot or forefoot has not demonstrated improvements in running economy nor a reduction in injury risk by itself. (PubMed)
Thus, the practical recommendation would be much simpler:
Don’t think first about where the foot lands. Think about running relaxed, with a comfortable stride, without artificially lengthening it and without striking the ground.
What benefits can it offer?
Slow jogging shares many benefits with low-intensity aerobic exercise: improved cardiorespiratory capacity, increased energy expenditure, and stimulation of leg muscles, in addition to allowing you to accumulate activity in a relatively comfortable manner.
In a trial with 81 adults around 71 years old, a 12-week program combining one-minute intervals of slow jogging and one minute of walking significantly improved aerobic capacity and performance on the chair-stand test. Improvements were also observed in various measures related to leg body composition.
The research specifically on Tanaka’s method remains limited, so we should not attribute miraculous properties. What it does have behind it is a solid principle: regular aerobic exercise is one of the best strategies to improve and maintain physical capacity.
A tool also for trained runners
Here is one of the most interesting applications for Sport Life readers.
Slow running is not only for beginners or older individuals. A trained runner can use it for:
The Natural Running Center’s philosophy also presents it as a recovery tool: the activity should ideally leave you better than you were before you started, not add more stress to what you already accumulate in daily life. (Natural Running Center)
And what about fat loss?
Running slowly does not have a magical effect on body fat. Fat loss depends on the energy balance maintained over time and factors such as diet, physical activity, rest, and body composition.
Its advantage may lie elsewhere: a comfortable intensity makes it easier for some people to maintain activity longer and turn it into a sustainable habit.
For an athlete, furthermore, easy aerobic work can complement quality sessions without adding as much fatigue as intense workouts.
Slow running and longevity
Perhaps this is the idea that matters most: running slowly can help you keep running for many years.
We don’t need all our sessions to be intense. Endurance training yields important cardiovascular and metabolic adaptations, while low-intensity work allows accumulating volume and staying active with a lower recovery cost.
Therefore, slow running can be part of a longevity strategy: it’s not about training less, but about learning when it is worth training more slowly.
6 mistakes you must avoid
1. Turn it into a race.
If you go out thinking you have to prove how much you can run, you’ve missed the point.
2. Obsess over the pace.
The 6-7 km/h is a reference, not a duty. Your slow running pace depends on your fitness level.
3. Forcing a midfoot strike.
Do not alter your striking pattern thinking it’s healthier. The strike pattern is individual, and the evidence does not justify making it an obsession.
4. Running too long on day one.
Slow does not mean there is no load. The body needs adaptation.
5. Thinking it substitutes all training.
A runner also needs strength, mobility, high-quality sessions when appropriate, and rest.
6. Ignoring pain.
Running slowly does not make an injury safe. If persistent pain appears or it alters your running form, stop and assess what’s going on.
SPORT LIFE TEST: ARE YOU RUNNING SLOW ENOUGH?
Take this test on your next run:
✓ You can hold a conversation.
✓ You can smile without effort.
✓ You don’t feel like you’re competing.
✓ Your breathing stays controlled.
✓ You finish with the sense that you could have kept going.
If you meet all five, you’ve probably found your slow running.
And there’s something more important: don’t be afraid of being overtaken by walkers. It’s one of the fun ideas of Tanaka’s method and also appears in the Natural Running Center approach: if you need to run very slowly, run very slowly. Other people’s speed has nothing to do with your training. (Natural Running Center)
IN SUMMARY
SLOW RUNNING = RUN SLOW + RELAXATION + CONSISTENCY
Intensity: low and comfortable, at a conversational pace.
Reference: the “niko niko,” running with a sensation comfortable enough to be able to smile.
Technique: a natural and relaxed stride. It’s not necessary to force a midfoot strike.
Ideal for: beginners, experienced runners, recovery runs, and athletes who want to increase their aerobic activity.
Key: not chasing pace, but controlling the effort.
Philosophy: running today in a way that lets you run again tomorrow.
TO REMEMBER A QUOTE
“If you can’t smile, you’re probably running too fast.”
More than a rigid scientific rule, it’s the best practical translation of Tanaka’s niko niko philosophy: make running feel easy, sustainable, and enjoyable again.
Scientific references