Being naturally slow helps but LSD training definitely makes you strong. It is not only the body that benefits, but also the mind. I must admit that even though a LSD run is much harder on the body, a LSD cycle is harder for me because it is much harder on the mind. That's my experience anyway. It is good for sure because the mind needs to be strong for any event.
We've been doing regular LSD rides over the weekends and I can feel the benefits clearly. Sitting on the bike for many hours needs practice. This is necessary for the bum and also for the hands and arms.
It is also the best way to experiment with gear and food and drinks. Time is no concern so you can focus on other aspects of your running or cycling.
Happy training everyone!