EST, IMHO the 50 minute setting is too long. We have dedicated protocols in the Globus machines sold in North America, that take only 25 minutes for Endurance.
Besides Endurance we offer Ultra-Endurance programs that hit higher stimulation frequencies. These frequencies are situated between slow-twitch and fast-twitch fibers. Our rationale is that if you are seriously training for endurance events, there is no way you can develop the wattage needed, relying purely on slow-twitch fibers. Therefore you need to train at the same time slow-twitch and fast-twitch.