Before we answer the question, let me highlight some of the benefits of regular physical activity:
• Lower blood lipids. Lipids are fatty substances, an excess of which can cause fat deposits in the artery walls, increasing your risk of heart disease.
• Improved glucose regulation. The body functions better when glucose (blood sugar) is maintained within a tight range.
• Improved insulin sensitivity (if you are insulin resistant you are at higher risk of type-2 diabetes)
• Reduction in blood pressure (reduced risk of heart attack and stroke)
• Improved psychological well-being - reduced stress, anxiety and depression
I prefer, then, to emphasise the health and well-being benefits associated with any regular physical activity rather than focusing simply on calories. This is particularly true when losing body fat is the goal.
Key point: If you’re looking to lose body fat, let nutrition be the priority where your energy deficit does the ‘fat burning’ and have training/physical activity support it.
As for walking versus running over the same distance, yes, there is a difference in calories per mile and variation will depend on an individual’s age, weight, body composition, running experience, pace and physical fitness.
The more intense the activity, the greater demand for fuel (glycogen and fat) and energy to be produced at the same rate.
Further, running will have a slightly greater ‘afterburn’ effect, known as excess post-exercise oxygen consumption (EPOC). In this study performed over one mile, EPOC remained elevated for 10 minutes for walkers and 15 minutes for runners. While the difference in energy expenditure and EPOC combined was about 30%, this amounted to just 48 calories. Nothing to write home about!
However, over longer distances and if done regularly, the difference may be more impactful. As a result, running may be preferable for people who want to expend more calories in less time.
However, that is NOT to say that running is a superior mode of exercise for everyone.
Walking, by comparison, can be an easy and seamless way to increase energy expenditure every day and has minimal impact on recovery and injury risk when compared to higher-intensity activities.
Also, for shifting body fat and creating a greater energy deficit, you will want to maximise the distance travelled (work done) but without significantly affecting hunger.
To that end, running may result in greater fatigue, glycogen depletion, and thus can be a sure-fire way to stimulate hunger and food cravings. In contrast, walking the same distance is less likely to be compensated for by reaching for food and therefore more likely to result in an actual energy deficit.
For those wanting to optimise body composition, my bias would lean towards low-intensity activities such as walking to complement a well-designed resistance training programme. (Also, if you are keen to gain muscle, running long distances encourages your muscles to adapt for endurance rather than to increase in size.)
If you prefer a more balanced approach, include a combination of resistance training and low intensity activity with some moderate-high intensity activity for cardiovascular fitness.
Ultimately, the decision should come down to what you love most. With exercise, place less emphasis towards the calories burned and more on how much better you feel after doing it. Again – let your calorie deficit through what you consume do the ‘fat burning’, supplemented and complemented by physical activity for overall good health.
Nutritionist and Bodyscan Consultant
firstname.lastname@example.org | phone 020 3490 4171 | Company no: 08807421