Here's the takeaway for 1600m at 86m/min or 160m/min:
So you burn about 30% more calories by running the same distance at just under twice walking speed.
...for the first ten minutes. I'm not up on my exercise science but speaking from personal experience, my circulation isn't even properly going for the first mile. The runners were also done in ten minutes, while the walkers were done in 20... so if you're comparing time instead of distance, the runners are burning 160% more calories.