CF works, no doubt ( I own a CF box though so maybe a bit bias). The thing with CF is that it doesn't target specific muscle imbalances and is not targeted to cycling specifically. Yes, it helps with general conditioning and strength, and also is invaluable when it comes to HR intervals etc, but you are able to achieve MUCH better results training specifically, with a certain element of CF. Knee pain, lower back pain etc are normally symptoms of muscle imbalance, even upper back pain while riding. Hamstring , glute , stabilisers are what we target , Single leg exercises to avoid compensation by the dominant muscles etc. If you in and around the Fourways area, give me a shout, join us one evening and you can see for yourself what it is we do.