This article doesn't compare cardio equipment in any formal way. Rather, the writer talks to experts (mainly TreadmillDoctor.com's Jon Stevenson) about what features to look for in a treadmill, elliptical trainer, rowing machine and exercise bike. Daly says you can find a good bike for $300 to $500, and that they don't usually need much service compared to other types of equipment. Recumbent bikes in general are recommended. Stevenson advises getting a model with a heart rate control that automatically shifts resistance to keep you in the fat-burning zone. The Epic 420R is noted as the editor's pick, but no particular reasons are given.
