The '20 minute tempo run'

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Darth Pariah wrote:

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Smoove wrote:

I wasn't struggling at all, I just didn't think an adult would be as dogmatically literal as my 9 year old; I expected a higher degree of nuance.

Darth, if you would handle this one next, that would be great.

http://www.letsrun.com/forum/flat_read.php?thread=8651585

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I'm more familiar with the biochemistry than the physiology, but this one is easy. Unequivocal proof of pariah's trolliness. Your answer was essentially, "It increases VO2max," which is correct and supported by literature. Please consider pariah to be what his name suggests: outcast.

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At maximal exercise, the majority of evidence points to a VO2max that is limited by oxygen supply, and cardiac output (Q) seems to be the major factor in determining oxygen delivery (28).

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http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.594.6219&rep=rep1&type=pdf

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Smoove wrote:

I think it is hard to say that it is a motivation or psychological issue that limited my absolute performance. I train more than ever and train as intensely as I did when I was in college. I've got more years of consistent volume than I ever did in college. Yet my performances slowed down by :63 (track) to :69 (road) as compared to college, with those times being in line when adjusted. It seems prettt clear that there is a change in physiology somewhere, and it is in line with the norms established by other performances. Muscle tone is a bit lower than in college, but I'm still at or near a single digit body fat percentage, so that could explain part of it, but not a full minute. It strikes me as a function of decreased cardiovascular capacity.

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NUFCrichard wrote:

This thread is getting fairly painful to read. I find Steve Magness's podcast to be similar.
You can question everthing and look into every molecule being broken down and resynthesized, but at the end of the day, you just want to be able to run faster.

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ATP hydolysis is the source of H+, but pyruvic acid and lactic acid don't exist in the body, because the steps of glycolysis and glycogenolysis don't have an H+ to give up, they don't dissociate.

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How does that help a runner get faster? 20 minute tempo runs help people get faster. If the mechanism by which tempo runs get people faster is useful and can be optimized, then great, but discussing which molecule gives up a proton isn't important for runners.

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I rarely run 200s any more (the only real test a former 5000m and now mostly marathon guy will likely use to gauge speed), and rarely go to the well when I do; but I am sure my speed has diminished. I think the fastest 200 I ran was a 26-mid at the end of a rep workout in college, and I don't know that I could run much faster than a 28 now. I expect some of that is attributable to the fact that I rarely work at that pace, and I expect part of it is the effect of being 46 instead of 22.

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Varsity Lu wrote:

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Interesting.... wrote:

I don't understand that if you want to stop or rather feel like you want to stop after 20 minutes then surely you're going faster than your 1 hour pace, ergo too fast...?

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My thought is that if a person is going to race for an hour, they spend time physically resting and mentally preparing for that race. At the end of the race, they will be exhausted and need to recover for several days perhaps weeks. An hour race is no joke.

However, for a weekly workout, the preparation (both physical and mental) isn't as focused and targeted as for a race. And the goal is not to run the person to exhaustion, but to stimulate the body to clear lactate, which is why you limit the run to 20ish minutes. The pace, however, is the same as the 1 hour race. That still feels tough after 15 minutes. The difference is that the athlete stops after 20 min rather than completing the hour race. In a race, the athlete would probably not feel that way until halfway due to the added rest, mental preparation, and race day adrenaline. In a weekly workout, you feel it sooner.

Not sure if that makes sense or properly answers the question.

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Smoove wrote:

I rarely run 200s any more (the only real test a former 5000m and now mostly marathon guy will likely use to gauge speed), and rarely go to the well when I do; but I am sure my speed has diminished. I think the fastest 200 I ran was a 26-mid at the end of a rep workout in college, and I don't know that I could run much faster than a 28 now. I expect some of that is attributable to the fact that I rarely work at that pace, and I expect part of it is the effect of being 46 instead of 22.

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Varsity Lu wrote:

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Interesting.... wrote:

I don't understand that if you want to stop or rather feel like you want to stop after 20 minutes then surely you're going faster than your 1 hour pace, ergo too fast...?

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My thought is that if a person is going to race for an hour, they spend time physically resting and mentally preparing for that race. At the end of the race, they will be exhausted and need to recover for several days perhaps weeks. An hour race is no joke.

However, for a weekly workout, the preparation (both physical and mental) isn't as focused and targeted as for a race. And the goal is not to run the person to exhaustion, but to stimulate the body to clear lactate, which is why you limit the run to 20ish minutes. The pace, however, is the same as the 1 hour race. That still feels tough after 15 minutes. The difference is that the athlete stops after 20 min rather than completing the hour race. In a race, the athlete would probably not feel that way until halfway due to the added rest, mental preparation, and race day adrenaline. In a weekly workout, you feel it sooner.

Not sure if that makes sense or properly answers the question.

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Don't have my books in front of me but I'm pretty sure Daniel's defines LT as the pace at which you could race for 50-60 minutes. Pretty sure he uses the word race, not run, so I've always taken that be under true race conditions. Anyone have a copy in front of them?

Correct. Page 113 of 2nd edition: "[Y]our effort should be one that you could maintain for about an hour in a race,"

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NUFCrichard wrote:

This thread is getting fairly painful to read. I find Steve Magness's podcast to be similar.
You can question everthing and look into every molecule being broken down and resynthesized, but at the end of the day, you just want to be able to run faster.

---

ATP hydolysis is the source of H+, but pyruvic acid and lactic acid don't exist in the body, because the steps of glycolysis and glycogenolysis don't have an H+ to give up, they don't dissociate.

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How does that help a runner get faster? 20 minute tempo runs help people get faster. If the mechanism by which tempo runs get people faster is useful and can be optimized, then great, but discussing which molecule gives up a proton isn't important for runners.

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There is certainly a balance that we should try to strike between being absorbed by the minutia on the one hand, and understanding the processes that are taking place on the other so that we can get the most out of our workouts.

For example, understanding that the purpose of doing a lactate threshold work out (from my training program) is to deal with the accumulation of waste products associated with anaerobic respiration allows me to adjust workouts on the fly while still getting the desired benefit. If I go out for a 20 minute tempo run, but I'm not feeling great for one reason or another, I can adjust that work out on the fly and do 4 x 5 minutes at threshold pace with one minute of rest in between. Because of my understanding of the underlying physiology of the work out, I recognize that those one minute breaks will not detract from the overall quality of the work out. I also will opt to make those one minute breaks passive and rest breaks rather than active recovery. Since this will reduce the clearance of those waste products during the break. That will allow me to have higher volumes of those waste products throughout the course of the work out, thus more closely simulating the desired outcome of the 20 minute tempo run.

I maybe some will say that my understanding of the physiology is completely wrong, but the point of it all is that understanding the physiology can indeed matter and guide you when doing a work out.

But that's true for almost any workout Smoove. You can start a tempo workout knowing you want to improve your ability and strength to run at X pace and adjust effort and intensity based on how you feel without needing to worry about your mmol levels, acidity, or where the ions are currently attached to. Obviously there is some science behind the general principle that tempos should be run somewhere between 10k and HM pace but we don't need to geek ourselves out, like we've done on this thread.

20 minutes at 60 minute race pace is tough because most people use the pace they ran in their PR race, or a race from weeks or months ago, as reference. Some mess it up further by using a goal pace or some other metric they are not ready to run.

Example of not accounting for how you feel on any given day:

John raced 10 miles in 60 minutes two weeks ago. He was peaked, rested, wearing flats and the race course was flat. He is still in that shape, but it is after a 9 hour workday when he sets out to run his 20 min LT tempo run, he sets out at 6 min pace and is huffing and puffing at the 2 mile mark (12 minutes into the run). He runs for 8 more minutes to make it 20 min in total, but he is pretty beat when it is over. The reason why is that John really could only have truly kept 6 flat pace for 40-45 minutes on that particular day. John should have been running closer to 6:20 pace on his 20 min LT tempo run since he probably could have only mustered 63:20 in a 10 mile race on his particular training day. The gap between how one feels and how one raced could be even greater than 20 seconds per mile.

See how a runner could really mess this up if he didn't have a recent 60 minute race result?

If John had not raced 10 miles in 60 minutes, but instead he simply guesstimated he was in 58:20 10-mile shape and set out to run his 20 min LT tempo run at 5:50 pace (when he really is a 60 min 10 mile guy, who is still tired from his 9 hour work day, not tapered, etc.) he is now off by 30 seconds per mile from true LT effort on that particular training day. In essence, he is running 20 min at 30 min race pace. That may as well be a race-like effort because it is continuous running that is 2/3 of the actual full-race duration. Would any 15:35 5k guy run a 10:00 2-mile in training and think of it as a typical training run? How would a 3:43 1500m guy view 1000m in 2:30 on a typical training day? Certainly not as a tempo run.

My $0.02

I understand that criticism, but I am not sure quite what it is a criticism of.

I certainly don't think you are suggesting that we throw threshold pace running out. My sense is that you are suggesting that (a) training by an incorrect VDOT score and (b) strict adherence to even an accurate VDOT score are both unwise.

I don't think anyone disagrees with that, and I don't know of anyone who advocates doing either of those. The fact that inexperienced or relatively uninformed runners may make those mistakes doesn't invalidate the basic underlying premise though. And I don't think the likelihood of those runners making mistakes like those are limited to a VDOT/Daniels approach. All approaches to training require some degree of experience and judgment to implement in an optimal or near optimal way.

Finally, Daniels himself gives several different ways to test intensity, with the pace dictated by the VDOT tables only being one of those methods. I think if he were to read this post, he would agree that running at the right perceived effort would be more important than running at a particular pace. The purpose of the VDOT approach is to establish a guideline for what that pace should be, and should be viewed as a starting point in the calculation of pace, not the conclusion of that calculation.

I appreciate the response but that's not quite what i'm asking. Let me rephrase - Is it the pace I can race that day or race on a day when I'm at my best? I don't know about you guys but for me what I'm capable of racing varies widely on a given day in the same week/month.

I'm more looking for a response from a physiological perspective. How does LT vary from day to day if at all?

That day. I just laid it all out there.

Agree with you jman1. Again, as I said earlier, this is where the art of coaching comes in. Also, there are other indicators of effort besides reading a table in a book. Knowing the athlete, the environmental conditions, the heart rates, listening to breathing, etc. All of those are ways to help figure out the right pace.

Another example: the first three weeks of our HS cc season is before school starts. We run early in the morning when it's cool and low humidity. I have my kids run a mile TT as a test of current fitness level. They all do great and I use that in conjunction with a local 5k race they did the week before to figure out their suggested LT pace. First day of school comes and it is blistering hot, humid, and the kids are running in the afternoon after their first full day of school. We are doing a LT run, but yeah, I'm adjusting the pace based on conditions.

The times in Daniel's tables are a good starting point, but fitness and effort is more fluid than a chart.

I didn't read the last paragraph closely enough the first time around. Thanks for the response!

One could say there is more danger in going too hard on a 20-min Tempo Run (and positive splitting or having form break down) than going too Easy. You go too Easy and you might hit "Uptempo" (aka closer to Marathon Pace). It is still a good "high end" aerobic stimulus....albeit probably too short for most marathoners (who may very well do 2 x 20min with a 5-min rest or something).

Now of course if you go too hard and cross the Threshold you are still getting benefits! You cross the threshold in Vo2max repeats/intervals and they are of course harder. You race a 3km/5km/10km and the pace is faster and it is harder. Good benefits in moderation.

But the context of the "20-min Tempo Run" as a workout alone is it is a great workout to slowly and consistently build fitness and stamina early on in a "aerobic base phase of training" (as well as in the Taper phase to not overtrain/over-strain). It is also a good "moderate workout" to have in a mix between the very hard and faster interval sessions (think Vo2max repeats like 6 x 1km etc.) and other workouts like hard Long Runs. A type of workout that could be done nearly every week out of the year.

Let's now consider a "timed-interval" session (I call it "Fartlek" although it is certainly not spontaneous like the origin of "speed play") session of 10 x(1-min hard, 1-min Easy). It is only a 20-min workout.

Now this workout can be as hard or as easy as we want it too be. We could run the 1-min hard sessions at faster than 5km pace and then "float" the recovery at a steady pace. In that case we could induce heart-rate spikes into the "Vo2max training" realm as we are certainly hitting velocity at Vo2max. We could be inducing a lot of lactic acid and have our form break down if we push really hard.

OR we could do the 1-min sessions at just around "only" 5km-10km pace and take a very easy 1-min on the jog sessions. In that scenario it is a much more moderate type of workout even though we are getting the legs used' faster running' at 5km/10km pace.

So in both cases the workout is 20-min long. If we average the HR data for the 20-min maybe it was around 85-90% (much like a straight-up 20-min steady, even paced "Tempo Run)....but maybe it was only 80% (on the easier side). So we induced a very different stimulus. We crossed the threshold and spiked the HR over 90% on the hard minutes, we got the legs moving faster than 5km pace etc.

Heck we could even do this workout as a session of 10 x 300m with a 1-min float/jog (more formal). What is it labeled as then? Well it depends exactly on the pace/intensity of the fast running and the pace/intensity of the recovery.

The point is we can choose how much lactate we want to induce. You want to always know the purpose of the workout in the context of the overall training plan and how it fits your racing/performance goals. No doubt you can get in shape trying to blast a 20-min "hard run" at 10km pace (faster than true LT), but then is that simply a time-trial race to see how long you can hold 10km pace?

Bottom line: Running Economy is the real key we want to develop. Throw Vo2max numbers out the window. That is the end goal. Running Economy is reflected of course in our Velocity-Pace at LT and our Velocity-Pace at Vo2max....which will be directly reflected in actual race performances from 3km-marathon. The Training and workouts we do are all to support this development of efficiency. In simple terms it obviously takes a mix of high mileage, LT workouts, Speed Training (be they "Reps" or Vo2max intervals. We train the systems at the neuromuscular level to improve form and mechanics, we strengthen the tendons and muscles, and we build mitochondria size/density and capillary beds and stroke volume (to name a few adaptations) etc.

On a final note check out some of the old "Lactate Shuttle" threads and research if you want to get more into the science on LT training specifically.