Running vs walking changes the comparison for weight loss

Running or walking for weight loss? Compare the research on distance, energy use and long-term results before choosing what fits your daily life.

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You have your shoes on and are standing by the door. You planned to run, but work has left you tired. If you walk the same route instead, have you taken the easy way out of losing weight? The distance may be unchanged, yet your watch will show a different time and a different energy estimate. Before deciding which activity wins, you need to decide what you are comparing.

Research approaches that question from several directions. Experiments in which the same people cover the same distance have found greater energy expenditure from running. A comparison involving walkers and runners with different body sizes found similar total expenditure per mile.[4][5] These results can coexist: the participants and the rules of the comparison were different. A number without those conditions can make a sensible study sound like a sweeping rule.

Energy used during a session and weight change over years also belong on different scorecards. A long-term study found a stronger relationship between changes in running and changes in body size, while another found similar associations between walking or running and several health outcomes when energy expenditure was comparable.[1][13] The useful starting point is to separate the measures used in these comparisons.

Running used more energy over the same distance in within-person tests

An experiment recruited 15 women and 15 men of average fitness and measured each participant walking and running 1,600 m. Their mean age was 21.90 years and mean body weight was 71.01 kg. Walking speed was set at 86 m per minute; running speed was 160 m per minute. Researchers measured oxygen consumption before, during and after exercise to assess energy expenditure.[4] This was a measurement through breathing, rather than a comparison of the figures displayed on participants’ watches.

During exercise, walking used 372.54 ± 78.16 kJ and running used 471.03 ± 100.67 kJ. A kilojoule, abbreviated kJ, is a unit of energy. When additional expenditure after exercise was included, the totals were 463.34 ± 80.38 kJ for walking and 664.00 ± 149.66 kJ for running.[4] Under these conditions, the same people used more energy running the same distance. The figures describe averages in young adults, and the variation around those averages matters too.

The comparison held distance constant while changing speed. It did not hold time constant. Running finished the journey sooner, whereas walking occupied a longer period.[4] That is relevant if your exercise plan is to complete a particular route. It leaves a different question open if your plan is to exercise for a fixed period before returning home. Neither question is unreasonable, but they should not be treated as interchangeable.

Postexercise expenditure returned to resting values 10 minutes after walking and 15 minutes after running.[4] Those timings give necessary context to claims that running keeps you burning energy afterward. Recovery was observed for 30 minutes after exercise. The experiment does not establish that a large additional expenditure continues into the following day.[4] It measured only the session and 30 minutes of recovery.

A second experiment examined body size under standardized conditions. It included 26 women who were not regularly active: 13 of normal weight and 13 with overweight or obesity. They completed a 1.609 km walk and jog on separate days, with the order randomized. Walking speed was 1.34 m per second and jogging speed was 2.23 m per second.[7] Here, researchers could examine both the activity and the participants’ body-size category within the same experimental framework.

For women of normal weight, expenditure was 280 ± 29 kJ during walking and 393 ± 46 kJ during jogging. For women with overweight or obesity, it was 356 ± 42 kJ and 490 ± 59 kJ, respectively.[7] Both the movement and the body being moved belong in the interpretation. Comparing only walking in the heavier group with jogging in the normal-weight group would mix a difference between activities with a difference between bodies.

All these women were able to run the specified distance continuously at the prescribed speed.[7] The findings therefore do not represent everyone starting a running habit, including people who need to stop along the way. That eligibility condition deserves to sit beside the distance and speed. Otherwise, a reader may turn a controlled comparison into an unfair judgment about choosing to walk.

Body size can change the apparent answer

Another study compared 19 normal-weight walkers, 11 overweight walkers and 20 marathon runners over a mile. Walkers used their preferred walking speed; runners used the speed of a recently completed marathon. Total expenditure was similar across the groups: 93.9 ± 15.0 kcal, 98.4 ± 29.9 kcal and 99.3 ± 10.8 kcal, respectively.[5] Read only as totals for a distance, those averages could seem to support the claim that walking and running cost the same.

However, this was a comparison between separate groups, rather than between walking and running in the same person. The overweight walkers had greater body weight and fat mass than the other groups.[5] This result is compatible with the experiments finding greater expenditure during running. Walking while moving a larger body was being compared with running by people of a different body size. The shared distance did not remove that difference between participants.

When expenditure was expressed per unit of body weight, marathon runners had the highest values, followed by normal-weight walkers and then overweight walkers. When it was expressed per unit of fat-free mass, the values were similar across groups. Fat-free mass means the parts of body weight other than fat.[5] The apparent difference depended on whether the researchers reported a total, a value relative to body weight, or a value relative to fat-free mass.

Body weight and sex were factors in the study’s prediction of energy expenditure.[5] If the person walking next to you gets a different energy figure, that difference is not automatically a verdict on either person’s technique. Ask whether the bodies and comparison conditions are alike before treating the figures as competing scores. This research shows why the word “same” needs a qualifier: same distance, same total energy, or same energy relative to a particular measure of body size.

Speed introduces another important exception. In an experiment involving 34 university students, participants performed walking and running tests on separate days while speeds increased in stages. At speeds exceeding 92 ± 2% of each participant’s maximum walking speed, walking used more energy than running at the same speed.[18] Near the upper limit of walking, expenditure did not simply rise in direct proportion to speed. Walking very fast was a distinct experimental condition.

This does not mean an ordinary stroll always uses more energy than jogging. The participants were young and approaching their walking-speed limit during an incremental test.[18] Comfortable walking and walking so fast that you feel ready to break into a run should not be merged into an undifferentiated activity called walking. The verb alone leaves out much of the exercise being compared.

Equal energy estimates do not guarantee equal weight change

The long-term evidence includes an observational study using questionnaires from 15,237 walkers and 32,216 runners. It assessed changes in exercise and body mass index, or BMI, from baseline to 6.2 years later.[1] BMI is a measure of body weight relative to height, rather than a direct measure of fat mass. The study followed people doing their chosen activities in everyday life. It did not assign them to start running or walking and then compare the effects.

Exercise was expressed in MET-hours per day. MET describes activity intensity, and combining it with duration provides a measure of exercise amount.[1] This changes the yardstick from that used in a same-distance laboratory experiment. The researchers were looking at how changes in questionnaire-assessed exercise energy expenditure related to changes in body size. They were not asking whether a walk and a run along an identical route had used identical amounts of energy.

At baseline, walkers of both sexes were heavier than runners and expended less energy walking than runners did running.[1] The groups differed before follow-up began. Their everyday food choices, reasons for choosing an activity and fitness could also differ. An analysis of equivalent changes in exercise amount is useful, but it takes place within those different lives. A matched statistical measure of exercise does not make every other condition equivalent.

Increases in both walking and running were associated with lower BMI, but the relationship was stronger for running in men and in heavier women. In the highest baseline BMI category, the study reported 90% greater weight loss associated with running than walking per equivalent change in exercise amount.[1] That is a comparison of statistical associations within particular groups. It is not a forecast that your weight loss will increase by 90% if you begin running tomorrow.

Numbers: walking and running comparisons

1,600 m: the distance walked and run by the same participants, at different prescribed speeds.[4]

372.54 / 471.03 kJ: mean expenditure during walking and running, respectively, excluding additional postexercise expenditure.[4]

93.9 / 98.4 / 99.3 kcal: mean expenditure over a mile in normal-weight walkers, overweight walkers and marathon runners, respectively.[5]

6.2 years: follow-up comparing questionnaire-assessed exercise changes and BMI changes, rather than guaranteeing experimental weight loss.[1]

92 ± 2%: the proportion of maximum walking speed above which walking used more energy than running at an equivalent speed in university students.[18]