Walk more to burn fat

Why walking is one of the best forms of exercise to lose or maintain weight

Did you know that the humble act of walking can be more effective for burning fat stores in your body than other forms of exercise? Particularly when performed at a moderate intensity that aligns with the optimal fat-burning heart rate zone? Below is a summary of why and how this works, and with walking being perhaps the most accessible form of exercise to most people, I hope it encourages you to get more daily steps in!

The human bodies 2 main fuel sources

Firstly did you know that we generate the energy required to power our daily activities from 2 different types of fuel stores in our body?

1. Carbohydrates for fuel – Glucose (sugar) is our body’s main source of energy. It comes from carbohydrates in certain foods and fluids we consume (think cereals, pasta, bread etc etc). This is the fuel source we are most familiar with – and often we eat plenty of carbs before exercise to fuel us even more. When your body doesn’t immediately need the glucose from the food we eat for energy, it stores glucose primarily in our muscles and liver as glycogen for later use. If we consume more glucose than our glycogen stores can hold, our body converts the excess into fat…

Fat for fuel – Did you know that stored body fat is also an energy source for us? This was very useful in human evolutionary terms for thousands of years  – as food wasn’t always as abundant and easily accessible as it is now – so when our bodily carbohydrate energy stores where depleted – our stored fat was then used to fuel us when we didn’t have food immediately available to eat (as we had to be able to go and find it or hunt for it!) However in the modern age where food is easily available any time of day – we no longer have a need to go into fat burning mode (ketosis)  – and fat can inturn build up if we constantly eat more calories than we burn, and don’t go into fat burning mode

ABOUT The Fat-Burning Heart Rate Zone

• You can though train your body to use it’s fat stores for energy, and thus lose bodily fat.

• The body primarily uses it’s fat stores for fuel at lower intensities of exercise, such as walking, rather than from stored carbohydrates in the body (glucose/glycogen). We can only use glucose/glycogen to fuel high-intensity activities – when those stores are all used up duing high-intensity exercise – we crash and have little energy.

• To burn fat – we want to operate in the fat-burning heart rate zone, which is typically 50-65% of your maximum heart rate (MHR).

• To calculate your MHR, subtract your age from 220. For example, for a 40-year-old: 220 – 40 = 180 beats per minute (BPM).

• Your fat-burning zone would then be 90-117 BPM for this individual – and this is the heart rate zone you want to be in – which also happens to be the zone you are in when walking at a moderate pace1 If you run – you are above this zone.

• Smart watches actually can show your current heart rate, so you can clearly see what heart rate you are in when moving. However an even simpler way to know you are in a fat burn zone, is when you can easily hold a conversation when exercising/walking, it’s basically a moderate walking speed.

The first image shows the different heart rate zones according to age, with the fat burning zone being 50-65% of your MHR. 

We can also see on the phone screen a strenuos hiking activity, which is primarily producing a heart rate in the fat burning ‘yellow’ zone.

Why Walking is Effective for Fat Burning

1. Sustained Fat Utilisation: At lower heart rates, your body has enough oxygen to efficiently metabolise your fat as a primary energy source, it doesn’t need to tap into your bodies glycogen stores.

2. Lower Stress on the Body: Walking doesn’t cause the metabolic stress associated with high-intensity exercise, such as cortisol spikes, which can inhibit fat loss.

3. Extended Duration: Since walking is less taxing on the body, it can often be sustained for longer durations, leading to greater overall calorie and fat burn. Because walking can tap into fat stores for fuel – you can do this for a very long time and don’t need lots of stored bodily carbohydrates to use. Whereas when running for example, at higher heart rates, this has to tap into your carbohydrate stores (glucose/glycogen) – and when the stores are gone – we hit the so-called “wall” – no more carbs in the body – so we have to eat to replace the carbohydrates burned and build up those stores again.

Benefits of walking Compared to Other forms of Exercise

• Running or High-Intensity Workouts: These activities may burn more calories overall compared to walking but they shift energy utilisation away from stored fat to stored carbohydrates, especially as intensity rises above 70% MHR. The downside of using your glycogen stores is you need to eat to replenish them – this is why after high intensity exercise you get hunger cravings (often for carbs, sugary foods) so you may burn more calories in high intensity exercise – but you are also more likely to pig out after and put more calories back into your body!

• Aerobic Consistency: Walking provides steady aerobic exercise without pushing the body into anaerobic zones, which rely on quick-burning energy stores like glycogen. Inturn you just don’t get the hunger cravings after walking!

• Less stress on the body: Do you hear much about people getting injured from walking? It rarely happens – it’s very natural and gentle for the body to walk. You could do it every day and always recover well. Higher intensity exercises however can produce more injuries due to greater stress on the body. It’s often said that with running for example, at any one time – 25% of runners are injured! And if you run everyday then there is more chance of injury. It must be said though that running once or twice a week can be part of a good exercise programme.

Practical Tips for Fat-Burning Walks

• Track your Heart Rate: Use a heart rate monitor to stay in the 50-70% MHR zone.

• Incorporate Inclines: Walking on gentle hills or using a treadmill incline can increase calorie burn while keeping intensity moderate.

• Consistency: Aim for at least 30-60 minutes per session to maximise fat utilisation. 8-10,000 steps a day is a good target.

• Fasted Walking: Walking in a fasted state (e.g., before breakfast) can encourage the body to tap into fat stores even better.

In summary

Walking is an excellent low-impact, sustainable way to burn fat, especially when done in the fat-burning heart rate zone. It minimises strain on the body while promoting efficient energy usage.

If you wish to lose weight, or maintain weight – regular, daily walking really is one of the best forms of exercise to do this.

There are however countless other benefits to walking, as shown on this website, which I hope you discover too!

FURTHER RESOURCES

Everything You Need to Know to Burn Fat and Calories During Walks:
www.verywellfit.com/are-you-walking-in-the-fat-burning-zone

How your body burns fat and carbs during exercise:
www.hprc-online.org/physical-fitness/training-performance