Fast-slow walking is having a moment, with the interval-style workout gaining attention among over-50s. Here’s how Japanese walking works and whether it can really help reduce belly fat
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The combination of fast and slow walking, a type of interval training workout, could be one of the more enjoyable ways to help shift stubborn belly fat. It’s currently having a moment right now – with strong interest, particularly among people over 50, claiming it helps melt belly fat. The method, also known as “Japanese walking” normally involves a three minute fast walk, followed by a three minute slow one, for about 30 minutes. We asked personal trainer Anwen Davies, gym and fitness product developer at Net World Sports to explain how fast-slow walking can help reduce belly fat.
What is fast-slow walking?
As the name suggests, fast-slow walking, AKA interval walking, means alternating between a faster pace and a slower pace during a workout. Instead of continuous speed for half an hour, you instead walk fast for a few minutes, then slow down to recover, then go again.The origins behind this form of exercise are linked to research in Japan, where it is known as interval walking training.
It has become increasingly popular as a social media trend because it needs no equipment, no gym and you can squeeze it into busy schedules as it’s not hugely time consuming. The standard version is three minutes of fast walking followed by three minutes of slow walking, repeated five times. Which works out as a half-hour workout.
For those who might be disputing it as the latest fitness fad, there is substantial research behind the benefits of this form of walking. A 2019 Mayo Clinic Proceedings study of 679 middle-aged and older adults (average age 65) found that peak aerobic capacity improved by 14% over five months. Their composite score for lifestyle-related disease risk fell by 17%.
Can it help women over 50 lose belly fat?
Yes, it can help, but – as with any form of exercise – this isn’t going to help you shed belly fat alone. It has to form part of a healthy way of living that also includes strength work and healthy eating. For those expecting it to immediately make a difference to belly fat on its own, you’ll be waiting a while to see results, if at all.
There is no form of exercise that targets fat from an isolated area of the body. When you lose fat, you are losing it from multiple areas of the body, and this is dictated by both genetics and hormones. The good news is that walking is effective in reducing overall body fat and can help the way in which our bodies handle energy. Regular exercise is the best way to target losing belly fat and the deeper fat around the organs.
The research behind the benefits of interval walking did not entirely centre on fat loss, however. The main studies measured fitness, blood pressure, muscle strength and disease risk markers. So in terms of weight loss specifically, it’s more about how you’re performing this exercise and our knowledge on the impact of exercise on fat more broadly.
Why does fast-slow walking work?
There are four main reasons why this is so effective compared to other exercises, and they are all linked to one another.
It burns more energy than steady walking. The fast intervals sharply increase your heart rate and breathing, so you use more calories per minute than you would walking at a steadier pace. The slow intervals let you recover, so you can keep going for the full 30 minutes. Walking slowly at the same speed doesn’t do enough to challenge the body.
It builds fitness, and fitness changes how the body uses fuel. In the Mayo Clinic study, the researchers found that exercise intensity was more impactful than concentrating on the amount of exercise. 50 minutes a week of fast walking was seen as being the optimum amount to see benefits. A fitter heart and stronger leg muscles help you to exercise more with less effort, and you burn more over the day.
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It helps with blood sugar and insulin. Working muscles are crucial to help remove sugar from our bloodstreams. Regular exercise allows the body to prevent higher insulin levels, which is what leads to fat storage around our waists. Women over the age of 50 will particularly benefit from this because the body’s ability to deal with insulin tends to worsen at this stage of life.
It’s easy to maintain. The key to this is because it doesn’t take too long but is a dedicated amount of time, it helps give the exercise purpose – which will help it become sustainable. It’s also much less physically demanding on our bodies than running or HIIT classes. Fat loss is likeliest to happen when you’re doing something consistently for months rather than dipping in and out, so finding an exercise, whether it’s interval walking or not, that won’t fade after a week is incredibly beneficial.
Any extra calories burned after the session are a negligible number, so don’t expect the kind of ‘afterburn’ effect you may experience from more intense exercises. The repeatability is the important thing here – tangible weight loss will occur from doing this day in, day out.
Why is it popular with midlife women in particular?
Many women will notice their waistline changing around menopause, even if eating and exercise habits haven’t changed. Oestrogen helps direct fat to the hips, thighs and backside. But this stage of life coincides with levels falling and as a result, fat is redistributed elsewhere, including to our midriffs, including the deeper fat that surrounds the organs. Muscle mass levels typically drop too, which slows the metabolism. As discussed, insulin response and even our quality of sleep can be impacted too, and both make belly fat harder to shift.
It’s a good job then that fast-slow walking can address nearly all of those areas. It builds fitness, aids blood sugar control and keeps the legs active. It is also gentle enough for women who are managing their bodies through this stage of life, including stiff joints or if just starting out and the base fitness level is lower than those already exercising regularly. A walk can be done wherever you want and done at your own pace.
To make clear though, this should not come at the expense of strength training. Strength work is the best way to retain muscle, and that is why I always recommend pairing the two.
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What does a fast-slow walking session look like?
This is a standard session. It takes 36 minutes in total, with 30 minutes of intervals in the middle and a three-minute warm-up and cool-down either side. Use a scale of 1 to 10 for effort, where 1 is sitting still and 10 is your maximum pace.
Warm-up: 3 minutes, easy pace, effort 3 out of 10.
Fast interval: 3 minutes, brisk pace, effort 7 to 8 out of 10
Slow interval: 3 minutes, easy pace, effort 4 out of 10
Repeat fast and slow: 4 more times, as above, five fast and slow intervals in total
Cool-down: 3 minutes, very easy pace, effort 2 out of 10
The fast pace should be somewhere around 75% of your fastest walking speed. It should feel like a challenge, but not like a sprint or a jog. If you can chat easily during the fast interval, pick up the pace. If you’re struggling though ease off a little. This should still feel comfortable.
A smartwatch isn’t needed. The talk test works well and is what I use with clients.
Tips for getting started
• Scale up as you go. If five fast intervals is too much to begin with, start out with three rounds and build up over the course of a few weeks.
• Talk to gauge your pace. You should be able to say only a few words at your top speed and speak at a normal pace when walking slower.
• Frame is important. Keep your chest up, shoulders relaxed and arms swinging, because good posture lets you walk faster and works the muscles in your back and core more efficiently than if crouched over.
• Choose sensible footwear. Comfortable, cushioned shoes protect your feet and knees on harder surfaces.
• Pick your preferred route. A flat path or park is easiest to start with, and gentle hills can be added later as a way to raise the effort.
• Time it simply. Use a phone timer or a playlist with songs of a set length, so you don’t have to keep checking a watch.
• Aim for consistency. Three or four sessions a week that feel comfortable is the way to go rather than one big effort that leaves you feeling tired.
A four-week fast-slow walking plan to follow:
This plan builds up gradually. Each session includes a 3-minute warm-up and a 3-minute cool-down.
Week 1: 3 sessions per week, 3 fast and slow rounds, 2 min fast length vs 3 min slow length, 15 min total interval time.
Week 2: 3 sessions per week, 4 fast and slow rounds, 3 min fast length vs 3 min slow length, 24 min total interval time.
Week 3: 4 sessions per week, 5 fast and slow rounds, 3 min fast length vs 3 min slow length, 30 min total interval time.
Week 4: 4 sessions per week, 5 fast and slow rounds, 3 min fast length vs 2 min slow length, 25 min total interval time (with harder fast intervals).
From week 5 onwards, keep the 3-minute fast pattern and 3-minute slow pattern with five rounds, four times a week. If that starts to feel easy, walk the fast intervals a little quicker or add a gentle incline to keep developing the workout.