Skuj wrote:
To expand, this is a serious inquiry.
There are many "fartlek" discussions I'm sure. But I'm wondering if ALL speedwork requirements can be met, even for 800m/1500m people, within a "continuous run".
The answer is, of course, no. The 800 in particular requires a speed component that cannot be garnered through the exclusive use of continuous runs. Interval work is required for development of the speed component and interval work, by definition, requires near full recovery between reps.
If you are serious about learning about training programs, you may want to pick up one or two of the several good books on the market. For 800/1500 type training, I recommend a book titled "Better Training for Distance Runners". It was authored by David Martin, a well known sports physiologist, and the late Peter Coe who is best known for coaching his world class son Seb. You won't be disappointed with this book as it will answer many of your questions.