What is best to burn calories quickly?

This is going to sound like a cop out but - which ever one you are best at!

If you find running hard then you are not going to be able to do as much work running as, say swimming - likewise if your swimming technique sucks and you you need to rest for a minute after every length, you're better off, say cycling...

That said, according to MFP:

Swimming, breaststroke, general = 740 cals per hr
Running (jogging), 6 mph (10 min mile) = 740 cals per hr
Elliptical Trainer= 655 cals per hr
Bicycling, 12-14 mph, moderate (cycling, biking, bike riding) = 650 Cals per hour

To me, these are 'cruise speed' efforts - BUT


- I can do a half marathon outside at better than an 8 minute mile (1000 Cals per hour ~ 1666 Cals)
- I can do a 500 calorie x-country (mixed resistance) circuit on the elliptical for 30 minutes - but find it hard to keep going more than 45 so I tend to swap machines in longer circuits
- ditto running machines
- ditto rowing
- I can quite happily ride a bike at 14mph for 4 hours (2300 Cals)



In other words - play to your time available and your personal strengths.