no i dont want to put on muscle i just want to lose a bit weight, and its simply cycling, walking, swimming
exercise your abdominal muscles.
Swimming a given number of lengths will burn the same amount of calories regardless of the intensity. Swimming speed merely affects heart rate, breathing rate and time taken. The same applies to running and walking - running x miles burns the same amount of energy as if walking x miles. Ideally, you should be working at a rate that causes you to breathe deeply, have an increased heart rate; you should be in the 'fat-burning zone'.
OK, just done a quick google search - turns out I'm getting confused! In terms of burning calories hornblower was right - it is just distance. I was getting mixed up with getting fitter when the intensity does matter.