I have no idea why people feel the need to pick between the two. Unless you're trying to get ready for some very specific event or carrying huge amounts of extra fat, speed of weight loss doesn't really matter much, the important thing is picking a regimen you actually enjoy and will stick with. The idea that burning 500+ calories per day is a "waste of time" for weight loss is really silly. Put another way, how many fat people do you see in triathlons?
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This is just not uniformly true. The two activities place different types of strain on the knee and different people have different weak points in their knees. I can run 40 or 50 miles in a week and come away with zero knee pain. Riding difficult hills on a bike consistently leaves me with some joint pain. I'm far from an outlier in this regard.