hiking is probably a bit better, but walking only burns 2/3s the calories that running does for a given unit of distance.

So a 190lb man burns 150 calories for running a mile, but only 100 calories for walking it. It will take about 20 minutes to walk a mile, and about 10 minutes to run one.

So this relates to the original complaint about exercise 20 minutes a couple times a week: if you walk 20 minutes, you've burned... 100 calories.

A 1000 calorie hike is probably 10+ miles, and that's about 200 minutes. 3 hours and 20 minutes! Yup, quite the time commitment, however if you ran 7 miles it would only take about an hour.