Here is a sample H.I.I.T. workout.  Give it a try and then go through the stretching routine which you will find by clicking the link below

http://www.ptonthenet.com/capview.aspx?s=MjEzNjc5LDIwMTIsMywyNSw0LDU5LEZhbHNlIHg0WVA4NEpNYXI4S3YxY3F0Q2E3MWc9PQ==&p=1329308&e=677

H.I.I.T.

If this is your first time going through this type of workout do at least 15 min but no more than 20 min.  If this is not your first time, try  to get through 20-30 mins.  Ready!?! The intensity scale will be between 0-10, 0 being a very slow walk and 10 being an all out sprint.  This is the ratio, 10 sec at a level 8 intensity to 20 sec at a level 3 intensity.  Make sure you are good and warmed up before you start your first sprint.  Take a brisk walk or a slow jog for 5-10 min and then begin the intervals.  Have a great workout!