30sec-1min sprint followed by 5 minute walk, then repeat, etc
That "sounds" like someone's implying HIIT (High Intensity Interval Training)....but the "intervals" described are too long for a rest period.
You may burn more calories, but less of those calories are from fat. Low intensity workouts burn a greater % of calories from fat.
You burn the same amount of calories. THIS is where what's going INTO your body is so important. How/When you train is also important (fasted v. non-fasted).....and training "right" is important. Cardio shouldn't be done for more than 45minutes....or you WILL be burning muscle. Jury's still out on fasted cardio...and I do it a few times a week. I make sure I do that protein thing when I do. I'll take my chances.
I lost weight at a VERY fast pace in 2004 (from just under 230 to 191). It was amazing. I was also running 5mi. on an empty stomach....first thing in the morning. I lost a ton of lean muscle doing this....and I'm not going to go that route, again. Like I said....I don't care if I lose another pound....as long as I replace what I'm losing with LM....I couldn't care less.