LT training for "me" , and what "I" consider LT training , is training at a level of intensity that is slightly below ones actual lactate threshold....with occasional spurts at LT that often can't seem to be avoided.
It is the level of intensity that you can hold at which blood lactate is high but steady.....I think this definition varies a bit from physiologist to physiologist . I think most guys that are half decent shape could hold actual LT intensity for an hour or so...maybe more.
I come from a running background and in running it is slightly less than 10 K race pace. Probably more accurately ones LT intensity(pace in running) is likely what you can race a 15K to half marathon.
Most decent runners can run a 10 K in under 45 minutes and at least half of that time is run ABOVE LT if you race correctly.
....so it's a level of intensity a little BELOW what you can actually race for 45 minutes....I think that this applies to cycling as well and it is likely an intensity level just under what you could race a 45 minute time trial.
I don't have a power meter so I don't know what my power output is at LT....but in regard to heart rate I think it is about 88-90% of my maximum heart rate, as long as other things have not greatly affected my HR like heat, dehydration, over reaching etc etc. SO>>>.I try to train a little under that.
BY FEEL...I think you know you are at LT when you start to feel tight in the upper body inspite of all efforts to relax...and your breathing starts to get hard to control in a relaxed rhythmic manner.
As far as aerobic base improving LT....well yes it sure dose but only to a point I think. Besides not everyone has enough time to ride each week to get the "ideal base"......and just what is that ideal base anyway...depends on your goals I guess.
So I do think you can improve LT A LOT even without a large "base"
Geting back to running as an example of this...
I know men that run sub 35 minute 10 k's training only 40-50 miles per week....but they give LT training a lot of importance in their training.
In cycling I also think this would apply...I think you could develope a very high LT and be very good at Time trials etc with a lot less "base" than many people think you need.....after all how many of use are racing 4-7 hours at a crack.
I have a wife, full time job, and three small kids and thus I am trying to get the "most bang" for the time I ride. I think the majority of the readers on this board are after the same thing.
In running I simply could not do LT training more than once and occasionally twice per week for any length of time without injury.
In cycling I am thinking MAYBE one can train LT 3 times a week as long as intervals are not done.??
As it is now I try to train LT once a week on the bike with a long climb, and once a week running on my treadmill since treadmill running is not that hard on the body.
I would like to try 3 LT workouts per week, along with a long ride once a week, and an medium intensity shorter aerobic ride another day each week and drop the running. Maybe I am nuts wanting to do this, or maybe I will have to drop the medium intensity weekly ride and just do three LT rides and one long ride in order to see improvement...I don't know.
I do know that I do not have a great deal of time to train on the bike and I want to get into as good a shape as I can with this limited time.....and in "my books" that means having a pretty high lactate threshold. Personally I think that if one has a high lacate threshold one can "stomach" their way through some pretty long rides and even long races without too much trouble.
....correct me if I am wrong but I think long low intensity rides are somewhat over-rated.
Ti