Do you have an INTERVAL TIMER!?! It will completely change the intensity of your workouts. My favorite timer is the one pictured called the Gym Boss. www.gymboss.com or there is a free app in the app store for your phone!
When I stopped doing long cardio and worked out in a shorter period of time with more intensity I got better results with weight loss, flat abs, joint pain, muscle gains etc...
Working out with an Interval Timer helps me get my best workout. And no, I do not get paid to endorse Gym Boss...maybe one day :)