Quote Originally Posted by Cassandra_Cain View Post
Plus weight lifting and endurance cycling combined have been shown to cause what's called an interference effect, which further limits the benefits.
Current studies (one study, actually) indicate that this is only true if you are participating in maximum strength and/or power phases of resistance training at the same time as you're working on aerobic endurance. If an athlete is following a periodized resistance training plan, any detriment to aerobic endurance disappears once those two phases of training have been completed.

And I don't have time to find the ref for this, but my understanding is there is only one study that even indicates this might be true. Nothing is black and white, remember?