The article is not yet available. Talking with Jay, I understand it confirms the initial research with more detailed examination of data. The issue is rpm, keeping it at 80-90 whether by tandem or machine driven bike while making sure the patient is providing energy, not just letting the bike turn the legs around. Measuring heart rate ensures the patient is putting forth energy. I asked him about people like me who keep the cadence on our own and he said that although there has been no specific research on solo cyclists, anecdotal information, plus common sense confirm that it's the cadence, and the fact that the heart rate is in the correct zone of 60-85% of MHR, not what kind of bike you're using to get it there, that counts.