I have been doing less and less long cardio sessions, and replacing them with intervals or sprints. Studies show that intervals burn more calories in less time, and also help maintain muscle. SIGN ME UP!
Here is workout you can modify for your gym! Try it out, and tell me what you think
3 minutes elliptical MODERATE pace
1 minute rower FAST pace
Repeat 4 more times (total 20 minutes)

Photo credits: Mike Byerly Photography, MUA: Amanda Kroon, Outfit: Lorna Jane