ok how about interval training on the treadmill.
8kph 2 minutes
14kph 2 minutes
8 kph 1 minute
14kph 2 minutes
8 kph 1 minute
14kph 2 minutes
8 kph 1 minute
14kph 2 minutes
8 kph 1 minute
14kph 2 minutes
i find this very useful. plus u have to make sure your diet is good.