Hi Ap405,
joe bloggs runs 70mpw for 2 years with 2 tinman sessions per week he runs 70 minute half marathon...joe wants to be great so bumps it up to 110 (not injured) with sessions as before,races terribly for 3 months but then runs 68 mins for a half in month 4 of high mileage, he continues to log 110 for the next 2 years and can still only manage 68 mins,so has he reaped all the benefits hes going to or is there more to come?And if there is what actually goes on physiologically over this long period of time?
Hard to predict where someone's max potential is, but I see what you are getting at with the spirit of the question. Essentially, "we know that high mileage is supposed to work, so how do we confirm that it is working (or isn't working)?" The science tells us that increased mileage will lead to, among other things, mitochondrial density, increased capillarization, and improved substrate utilization balance. However, the science will also tell us that "You can't PROVE that it is the high mileage" and not something else responsible for these improvements.
So what sorts of conclusions can we make? I would say the benefits of higher mileage are indirect and possibly immeasurable (given our current analytical technology) once you get over the 70-80 mile per week range. Based a sample size of n > 1,000,000 in an ongoing field study conducted by countless coaches and athletes, we know that higher mileage (when achieved through a sensible progression) tends to fortify the health of our connective tissue, in part through the release of growth hormone. The more healthy we are structurally, the more consistently we can train. Of course, there is the caveat that the mileage must be applied in a sensible manner with an appropriate blend of intensity. Let's not forget one of Tinman's guidelines: Run around 80-85 pct of your maximum load tolerance so you can effectively integrate all the training elements (endurance, stamina, speed) to achieve the proper balance. That max level can continue to increase, but if you stay around that 80-85 pct level, you won't even think of high mileage as being "high" because you will have found a "sweet spot" where the mileage is appropriate to support all the elements of your training.
In terms of when to "call it off" regarding a foray into high mileage, I would posit that if higher mileage isn't working, then either the progression has been too rapid or certain lifestyle factors are present that interfere with its effectiveness. Going from 70 to 100 in a few months is much different than running 90 for years and then bumping up to 100. Nevertheless, even with a sensible progression, as your mileage increases beyond 70-80-90, etc, you walk a much finer line with fatigue and injury. If things break down, is it the mileage that is too high, or is the support infrastructure not in place? Dr. Vigil had a great line for his athletes when he coached the squad at Mammoth Lakes: "We have you set up in an ideal situation here...If you get sick, it is your own fault." In the "real world", most people don't have this type of support network, but if we want high mileage to work it doesn't relieve us of the responsibility to make sure we are doing everything we can in terms of recovery, sleep, and nutrition.
One area that doesn't get as much attention as it should in the endurance sport world is the adaptability of the nervous system and the endocrine system. Over the long term, quite simply, the more we run the habituated we become to the activity. In terms of biochemical adaptations within these systems, Dr. Daniels has conducted some studies (not published, to the best of my knowledge) where his lab tested catecholamine levels in elite runners and found that elite runners had similar levels after easy ten mile runs as non-athletes had while at rest. In other words, an easy run did not arouse the "fight or flight" mechanisms in these athletes that we would expect to see after physical exertion.
While this finding alone would not justify higher mileage (after all, maybe the elite runners got really fit for reasons totally unrelated to mileage?), it does lend credence to the idea that as we become more efficient at the activity, the less taxing it becomes even if the difference in stress level is imperceptible. As a restorative tool, easy running can help promote a return to a more parasympathetic state (i.e. relaxed) so that we are more prepared for our next hard workout or race (and of course, more resistant to any health related setbacks). Again, these may not be short term adaptations, but over time, as mechanical efficiency and soft tissue quality improves so should our body's ability to regulate itself hormonally.
People tend scoff at some of the luxuries that Nike has invested into Salazar's squad, but tissue quality plays an important role in promoting overall training health. Sprint and field coaches/athletes as a whole have been ahead of the curve as compared to distance running, as those of us in the distance community tended to think only in quantifiable terms of vo2 max and thresholds and reserved our consideration of structural health only when things start to hurt. It might be counterintuitive on the surface to think that running more miles will help you recover better, but if you look closer, the nexus between higher mileage, mechanical efficiency, soft tissue quality, and neuroendocrine health is strong.
On one of the other threads, Carson (another Tinman athlete) had commented (in a good way) that there seemed to be no discernable pattern in how his plan was laid out. There's good reason behind that. The body as an organism is far too complex to be regulated by a cut and paste training plan. Optimum performance is about taking all of the key training elements and blending them into a recipe with the right ingredients. For this reason, I don't think we can look at mileage as a number or even in terms of "high" or "medium" or "low." Mileage is a critical part of the training blend for the role it plays in regulating our body as a complete system.
