Hi Trainee... Firstly dont be fooled in thinking more is better... I must run faster to burn more"
Its about the quality of the exercise, and i wouldn't recommend straight treadmill use as the only one particle for burning unwanted fat.
I can show you guys with what looks like zero percent of body fat on their bodies, guys who compete in bodybuilding shows, and show you their journals to proove they never use treadmills... Think about it, when your running at one point of the exercise both of your feet are eleviated into the air, now when your continuously running for say 10mins only 5mins of this have your feet been touching the ground... You may feel out of breath, but your body may be saying: i could of done better.
In many gyms there are stairmasters.. a revolving staircase that you continuously walk up. great machine, if you dont have access to one, walk up your staircase, then back down continuously... no need to run. faster is'nt always better... make sure you dont slip too
Hills - get outside and find some hilly places. run up the hill, then walk back down it or pace-walk down it.. run back up it again.
You can do these sort of exercises for hours on end without feeling out of breath, your body can physically cope with the demand and eventually get used to the demand and progress burning fuel more efficiently.
Weight will begin to slip off whilst your strength (particularly calf muscles) will strenghten bigtime.
Other cardio i'd recommdend is Swimming... do a fast paced lap to one end of the pool, then a slow breast stroke back to the start, then another fast paced swim, then breast stroke again... continue this until you drown
The idea is: do something energetic and fulfilling, then relaxing, then doing it again... this way your testosterone is fully commited to running up the hill or whatever, as it mentally knows it can relaxin in a minute or two.