A common misconception about cycling is that it is just like any other form of cardiovascular exercise similar to jogging or running. While it is true that this sport does provide an excellent cardiovascular workout, assuming that it would only be focusing on your endurance rather than your strength would be doing this amazing form of working out an enormous disservice.
The truth of the matter is that cycling can help you tackle both aspects of your physical fitness at the same time. All you need to do is adjust the settings in order to get the specific kind of experience that you need. For example, if you use your exercise bikes at a low setting, which means that the resistance that it is going to provide is minimal, you would experience an enormous boost in your endurance but not much in the way of strength training. That being said, if you increase the resistance the impact on your endurance will be minimal but you would get an excellent strength training experience out of the process because your muscles would have to really exert themselves and would reach failure, which is the point where they are no longer able to work, faster. Strength training is all about training to failure after all, and this is the best way to do it.
It is not just about the fact that you are exercising, it is how you use the exercise bikes that matters a lot as well. Just adjust the resistance based on your needs and there is no reason why you would not be able to get a truly fantastic experience while working out, and see all kinds of improvements to your physique and health in the long run.