Does it help if you do shorter exercise on the elliptical trainer and do it 2 times a day?

An effective elliptical workout can be completed in 15 to 20 minutes. The key to an effective elliptical workout is using intervals to build resistance. As you build resistance in those 15 to 20 minutes, instead of adding mroe time to your workout, opt to increase the incline or resistance level on the elliptical trainer.