does instense anaerobic training lower your aerobic ability?

Check out this thread:

Read what Renato writes about his 800 athletes and the posts from Tinman.

The surprising aerobic benefit of sprinting:

Summary: Six sessions of 30 second, all-out sprints over a two week period resulted in a doubling of endurance time to exhaustion and an impressive increase in muscle oxidative potential. These results stand in stark contrast to the traditional physiological explanation for the need for a base building phase and also challenge the belief that anaerobic exercise diminishes or negates the positive effects of aerobic training. The 100% improvement in endurance capacity shows that anaerobic training (i.e. sprints) can dramatically improve aerobic capacity and exercise performance in events that are primarily aerobic in nature.

http://www.powerrunning.com/Exercise%20Physiology/The%20Surprising%20Aerobic%20Benefit%20of%20Sprinting.htm

More research on the aerobic benefit of sprinting

Summary: Two follow-on research studies by the same research team that found significant improvements in endurance performance from sprint training confirm the findings of the initial study. The first follow-on study found significant improvements in endurance performance throughout 6 weeks of sprint training. The second follow-on study found that 30 second sprints, 60 second sprints, and 90-120 minutes of traditional endurance training all produced the same magnitude of improvement in a 2 minute time trial and a 1 hour time trial. These results challenge the belief that "aerobic" training and "anaerobic" training produce only distinct physiological and training adaptations. Instead, the results imply that the distinction between "aerobic" and "anaerobic" training may be artificial to some degree. The results further challenge the belief that "anaerobic" training interferes with "aerobic" development or causes a decline in "aerobic" capacity, at least in novice trainees. Traditional physiological beliefs of "aerobic" and "anaerobic" are unable to explain the results of these studies. The physiological model of shared "muscle factors" offers a logical alternative explanation for these results.

http://www.powerrunning.com/Exercise%20Physiology/More%20Research%20on%20the%20Aerobic%20Benefit%20of%20Sprinting.htm

Research published Feb 2006:

"This is also the first study to show that sprint training improves aerobic exercise performance during a laboratory time trial that closely stimulates the way in which athletes typically compete. Finally, the present data confirm the novel reults from our laboratory's recent study that showed skeletal muscle oxidative capacity can be enhanced by a brief 2-wk period of sprint training..."

Burgomaster K, Heigenhauser G, Gibala M., Effect of short-term sprint interval training on hman skeletal muscle carbohydrate metabolism during exercise and time-trial performance, Journal of Applied Physiology, 100: 2041-2047, 2006

i could be way off here, but this was always my understanding of base training and faster paced training.

the reason of the base was more about creating a strong body. idea was this could protect the body from the beating of interval training.

also, i thought it was pretty common to believe that fast interval training really gave you a boost aerobically, that is why you do it closer to top races. and because it is hard on body mentally and physically the best time to do it is close to the end of the season.

Key words in those research findings are '6 weeks', '2 weeks' . . . Contrary to what one of them said, this does not go against traditional theories. It's been known for a very long time that sprint training within 6 weeks will improve mostly aerobic performances.

Just to be clear, this by no means whatsoever justifies doing short intervals for long term aerobic improvement.

Actually, I should correct my last sentence, I should have said:

This my no means whatsoever justifies doing short intervals AS A MAJOR ELEMENT for long term aerobic improvement.

In other words, those strides after the normal and long runs are great things to do year round.