Physiological differences in two a day workouts

kaparzo said:

so i'm thinking of splitting two of my weekday rides in half, 2hrs per. doing 2hrs of SS mtbing or endurance riding in the morning and my intervals in the afternoon when i am more awake. I'm sure this has been discussed ad nauseum but i couldnt find anything.

my question is, do you make different adaptations? and is that morning ride beneficial at all? that's the real question i suppose.

Re: adaptations:
1) If your intensity for each ride is no different than the components' sum in a 4 hour ride, then you are likely giving up those physiologic adaptations associated with riding for 4 hours uninterrupted.
2) If you raise the intensity somewhat for each ride because they are shorter, you may be gaining those physiologic adaptations associated with riding at a higher intensity.

Re: Is the morning ride beneficial?
It depends on the specific demands of your target event(s), what type of riding you do during the morning ride, and at what point in the season you are in.

kaparzo said:

so i'm thinking of splitting two of my weekday rides in half, 2hrs per. doing 2hrs of SS mtbing or endurance riding in the morning and my intervals in the afternoon when i am more awake. i'm sure this has been discussed ad nauseum but i couldnt find anything.

my question is, do you make different adaptations? and is that morning ride beneficial at all? that's the real question i suppose.

If I'd been out for two hours in the morning at an appropriate pace then I certainly wouldn't be thinking about intervals in the afternoon. If intervals were required at whatever point of the season you're in then I'd give up the morning ride and do the intervals properly.

If you must do both I'd do one ride of a few hours and throw in some hard efforts in the latter half of the ride.