Last week was my first full week of real summer training. To me, summer training, and off-season training in general, is the most important training phase of the year. Lydiard wasn't kidding when he said that the base phase determines your performance level for the entire training cycle.
I think a lot of people either don't conceptualize or just don't understand summer training. In high school I just did easy runs for three months, came into preseason and started working out. I never ran as well in cross country as I did in track, and it's clear to me that it's because I let myself lose too much fitness over the summer. I would come into mid-August having run a lot of 60 mile weeks, but never run anything harder than easy runs. In the winter, I did long intervals and occasional tempo runs and always ran much better in May than I did in November. Last year, I had the best fall season of my life and I think a lot of it was because I decided to run a half marathon in mid-September. That forced me to get in good shape for that starting earlier than I ever had, and that fitness carried through for arguably the rest of the year.
Canova says that 80% of training is just training to train. By that he means that 80% of training could be considered foundation work for the highly specific workouts in the two months or so before a peak. Summer training for cross country is exclusively training to train. The whole point is to get your body ready to start working out and racing come September. It is a time for building strength and a big endurance base.
And now we arrive back at the big mistake: people don't have the right idea of what endurance means. Endurance training is by far the most general of the phases. It is an almost intentional lack of specificity. Over 50 years ago Lydiard showed everyone that endurance training works for every race 800m and up (unless the 800 guy is a sprinter moving up, then it probably wouldn't work very well). A lot of people also misunderstand Lydiard's base phase. It is NOT easy running; it is "steady running," and he set 100 mpw as a benchmark. That is really really hard to do, and it's also the main reason (along with periodization) why his principles are behind so many gold medal performances.
And finally on to what is the right way to train in the summer. I guess this is more accurately what I think is the best way to train in the off-season, since I'm not stupid enough to think I've got it all figured out. Part 1 lasts until you get up to whatever your desired peak mileage is. In my opinion it is best to get there sooner rather than later to give your body time to adjust to the workload before introducing another stimulus, i.e. workouts. Part 2 lasts for the rest of the summer, and consists of long tempo runs and intervals. These form a good mental break from the easy runs and are really the immediate precursor to XC-specific workouts.
Other stuff: I like to do hillsprints when I feel motivated enough. These are another thing a lot of people do wrong, because no one is really patient enough to do them with enough recovery. I'm not an expert but Canova is the authority on them and why they're a good idea. Bodyweight exercises and drills are probably a good idea too, if nothing else to strengthen your core and keep your form from getting too sloppy. Hitting the weight room for the compound lifts is good if you can find the time, but know what you're doing before you try and squat 300 and kill yourself.
