The two most basic training variables are power/speed (fast-twitch) and endurance (slow-twitch). Most of us dwell in the area in-between most of the time, with some combination of the two being employed for races of 2-60 min. duration, or of climbs that are more than 10 moves but are somewhat challenging. In order to avoid stagnation and to keep tabs on your current fitness status, it is good to have "go to" sessions for both elements. For instance, while I am working longer routes, I try to get in a bouldering session at least once a week on a standard circuit. This does little more than maintain a base level of power, but in the fall, when days are short and cool, I will have some framework on which to build fitness for 5.12 and 5.13 projects.
As far as the "Yin for the Yang" for my running fitness, this summer, I have been doing many longer approaches of hiking and scrambling, which keeps me aerobically fit (car-to-summit of South Early Winter Spire in 92 min. with a 35-lb pack... woot), but translates maybe 60% to my running. Consequently, I do a maintenance session of short speed work each week (see "Ghost Running") to keep the leg turnover in some kind of trim for more serious running this fall/winter.
It is testament to the decent climbing weather in Mazama this summer that my endurance running session, a long run, has been seriously neglected, since I typically need 2-3 days of recovery from hiking to make it happen. So yesterday, after a solid day of rain and several days "off" from serious hiking while shooting photos and sport climbing, I made the running trek up to Deadhorse Point on the Hart's Pass road, a round trip of almost two hours and 14 miles. For perspective, I haven't run longer than 6 miles at a time for over two months. So my challenge was to see if all that grunting of gear up to the Spires has been sufficient to allow me a decent, if slow, overdistance run. Ideally, I should be doing a run of at least 80-90 min. at least once a month, just for maintenance. Otherwise, I will have to make a longer transition back to a full running schedule when the time comes, not always a fun process, and one which can carry a heightened risk of injury.
The verdict: yes, I haven't COMPLETELY morphed into a pack mule, though I am far from impala-like. Combining several hours/day of hiking and scrambling with weekly running speed sessions has been enough to keep the running animal decently together.
A key element in making this a reasonably fun run was the following tune coming on to my Shuffle player at 90 minutes:
The Take Away: if you are training two or more sports in the course of the year, tag the power/speed component of your "off" season sport at least once every 1-2 weeks, and the endurance component at least every 2-4 weeks depending on what other cross-training you are doing. I was able to stretch the latter quite a bit this season, but after a few decades of doing this I can break the "rules" *very* carefully, like a chef can substitute spices and keep the overall flavor.