YES, very good. Cycling on a heavy mountain bike at an average speed of 20kph my [Michael] average heart rate is 120bpm, where on Chariot Skates it is 136bpm at the same speed. Riding the same bike for two hours, my average HR is 115bpm where on Chariot Skates it is 128bpm for two hours. I obviously could ride or skate harder but, overall, I feel I have had a much better work out after two or three hours skating than after two or three hours cycling.
The best part, in my experience, is that wheelskates are so much more fun than bicycles. After two or three hours on wheelskates I don’t want to stop because I am having so much fun. It feels so free and there are so many skills to learn and master. After one or two hours on a bike, my seat and hands are sore and I’m trying to think of ways to get comfortable. I have always found jogging to be great aerobic exercise but I have never got to a level where I found it to be fun. The same goes for swimming... I enjoy swimming, it is great exercise (particularly in the heat), it is always an effort and a challenge, but I have never really found it to be fun. From my experience, I find an hour or two skating is not only better aerobic exercise than cycling but it also exercises more muscle groups such as lower back, abdominal, even neck & shoulder and requires more coordination skills. I expect and hour or two of jogging or swimming may be better aerobically, although the skating would exert far less impact stress on your joints than jogging.