Road Bike Racing - Split Training impact on FT plan

I'm using one of Hunter Allen's off-season power plans and I thought I would throw a question out to this group since this seems to be where most of the powertap discussions occur...

I'm really crammed on time and have been dividing some of my workouts (usually the longer ones) into to shorter workouts. I typically only do this on what he calls aerobic base days and I am curious as to how this impacts the overall plan. Basically the plan will call for 2.5-3 hours at 240-300 watts. I will break this into two workouts of 1:15-1:30 (I realize I have two warm-up and cool down periods). My question is what is the difference between doing the training in one vs. two sessions? I can see that there may be a difference in muscular endurance benefit, but would there be any difference in aerobic conditioning? My major goal for the year is to improve my functional threshold power as I want to improve my time trialing this year (the average TT will be 40k-50k).

I'm using one of Hunter Allen's off-season power plans and I thought I would throw a question out to this group since this seems to be where most of the powertap discussions occur...

I'm really crammed on time and have been dividing some of my workouts (usually the longer ones) into to shorter workouts. I typically only do this on what he calls aerobic base days and I am curious as to how this impacts the overall plan. Basically the plan will call for 2.5-3 hours at 240-300 watts. I will break this into two workouts of 1:15-1:30 (I realize I have two warm-up and cool down periods). My question is what is the difference between doing the training in one vs. two sessions? I can see that there may be a difference in muscular endurance benefit, but would there be any difference in aerobic conditioning? My major goal for the year is to improve my functional threshold power as I want to improve my time trialing this year (the average TT will be 40k-50k).

The best answer is to ignore the question. your longest ride of the week should stay intact. All others can be split, and maybe even SHOULD be split (especially if you can get a nap in between). Two sessions gives you better results in general, though I would not consider warm up or cool down part of the given lenght of time. That way, the length of the workout is the work length.

If your only real concern is a 40k tt, then you do not have to worry about the long ride at all, as your longest event will be about 1 hour long.

+1 splitting the workouts will actually rev up your metabolism as well-- the time in-between the two sessions would have a greater impact-- you should expect to maintain the wattage required esp with more rest in-between... which means you have less excuses to slack off your second workout --

The best answer is to ignore the question. your longest ride of the week should stay intact. All others can be split, and maybe even SHOULD be split (especially if you can get a nap in between). Two sessions gives you better results in general, though I would not consider warm up or cool down part of the given lenght of time. That way, the length of the workout is the work length.

If your only real concern is a 40k tt, then you do not have to worry about the long ride at all, as your longest event will be about 1 hour long.

+1

Good -but loaded- question, no one can give a simple answer for this.

For intense workouts splitting them should help if you don’t count warm-up and cool down periods. Take a look at the impulse-response model, overtime, split workouts limit at the same ‘fitness” score as does the same volume of uninterrupted work… great! Now look at the ‘fatigue’ scores [The attached graphs use days but could well be any time unit for illustrative purposes]. The maximum fatigue values reached are significantly lower in the split exercise condition, which is nice in that you get the same fitness effect without ever having to reach very high fatigue levels that leave you feeling like ass. Win-win right?

http://i168.photobucket.com/albums/u164/Enthalpic/TRIMP480w2x240.jpg?t=1199906426

http://i168.photobucket.com/albums/u164/Enthalpic/TRIMP480w6x80.jpg?t=1199906555

Well if you believe in the energy-delivery / energy-depletion model of exercise performance/fatigue a split long ride will not yield the same performance gain as an uninterrupted one as you never reach that glycogen-depleted, waste-loaded state that you would otherwise. You won’t get deep into the “valley of fatigue” that leads to super compensation of the energy delivery system.

Personally I’m not a fan of the energy delivery model anyways so let’s dismiss that for now and look at Noakes Central Governor Theory. This theory suggests that exercise performance is limited by the central governor (the brain/nervous system) in order to prevent long-term damage to any organ. The governor monitors several conditions and will decrease muscle fiber activation if any of the parameters leave the safe zone. For example one of the monitors is the thermostat and will decrease muscle activation if you become overheated. Another regulator is the glycostat which will decrease activation if blood glucose levels are falling rapidly -which would lead to dangerous hypoglycemia if left unchecked.

Training, according to this model, is a combination of the system becoming more resilient to perturbations in the first place, as well as the central governor becoming more tolerant towards borderline dangerous levels of exercise. The brain in essence learns that “Ok I know I’ve safely reached this level of pain before so I will allow Johnny to keep exercising a little bit further and see how that is.” So you can see riding to near failure is important in this model and how that two short-duration moderate-intensity exercise bouts will not elicit the same response as a single bout that approaches failure. High intensity exercise always approaches failure almost by definition and is not effected much by splitting the workout.

The cardiovascular output model of exercise performance should also be indifferent to splitting the workout as the heart never approaches fatigue anyways -it’s always working- and sub maximal exercise isn’t really taxing it all than much anyways.

So there really is no good answer to your question other than to follow DrWJ’s great advice.

So there really is no good answer to your question other than to follow DrWJ’s great advice.

How the heck did that happen? I didn't MEAN to give good advice. Must be coincidence. :D

Wow. Very good info guys. Way above the normal BF quality of responses. I think my question was answered, but I will add one point of clarification. My big goal for the year is improving my TT, but I will still be doing many road races which would be more in the 2.5 hour range on average.