posted Feb-16-2006 09:23 PM            

quote:

---

Originally posted by leitnerj:
Why are you comparing easy runs below MAF to McMillan's easy runs?

---

Don't sweat it. Just me making something simple more complicated. The MAF predicted 5K + Mcmillan at least gives a ballpark estimate on potential marathon times.

--jm

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posted Feb-16-2006 09:37 PM               

quote:

---

Originally posted by junkmiles:
Don't sweat it. Just me making something simple more complicated. The MAF predicted 5K + Mcmillan at least gives a ballpark estimate on potential marathon times.

--jm

---

Actually, it seems that our wires are crossed and I'm trying to find
the disconnect, not for sweating it, just to make sure I didn't
miscalculate the numbers or something. Back to your example before,
if you're able to run 7:30 at MAF heart rate (180-age, +5 if you desire),
the table would predict a 3:02 marathon. How did you calculate 2:38?
That's definitely aggressive. If it's going in too many circles, just send
me an email so I can get a grasp on your thoughts. I've tried 4 examples,
including myself and they've all been within 5 minutes of marathon time.

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posted Feb-16-2006 10:34 PM            

quote:

---

Originally posted by leitnerj:

Actually, it seems that our wires are crossed and I'm trying to find
the disconnect, not for sweating it, just to make sure I didn't
miscalculate the numbers or something. Back to your example before,
if you're able to run 7:30 at MAF heart rate (180-age, +5 if you desire),
the table would predict a 3:02 marathon. How did you calculate 2:38?
That's definitely aggressive. If it's going in too many circles, just send
me an email so I can get a grasp on your thoughts. I've tried 4 examples,
including myself and they've all been within 5 minutes of marathon time.

---

You didn't miscalculate, but I was just speculating that extending the MAF predicted 5K out to marathon distance via mcmillan will under or over estimate. MAF pace must correlate to a training pace as defined by Mcmillan. In most cases, I assumed this would be recovery or easy run paces.

Let me explain my thinking step-by-step.

I take the MAF HR and place it context of traditional training zones (based on maxHR). I do this only because, that is how Mcmillan defines his training zones. I don't think it is unreasonable, since MAF is just an alternate, if opaque, method to define aerobic zones. It is not a different physiological theory. Also, mcmillan assumes (as it must) that a runner is properly trained for the given distance and is aerobically fit. This means there is a strong correlation between all race paces, as well as training paces.

I'll use you as an example. The following numbers may be off, but I'm working from memory, not slogging back through this thread.

Anyway, MAF HR for you is 144, but you do a lot of work at MAF-5 (139), with a maxHR of 210 your MAF range 139-144 falls inside the 65-70% maxHR. This is the zone Mcmillan defines as a recovery run. Therefore, your MAF pace would correlate to Mcmillan's training pace for a recovery run. 8:30 is not too shabby for a recovery run BTW. If you plug in your MAF predicted 5K time (20:38), you find it doesn't correlate to the recovery pace as defined by Mcmillan (9:11-9:41). I plug in a a 5K time (18:48) that gives a recovery pace of 8:30 (at the low-end to be conservative). This corresponds to a 3:03 marathon.

In my case, MAF falls right at 70%maxHR, and if I use 7:30 as a maf pace (a long way off right now ) then I get a 5K of 16:06 and a ~2:37 marathon. (I ballparked it in my last post).

Simply put, I think the maf predicted 5K performance, while somewhat accurate, probably under or over estimate potential marathon performance. For you it was conservative. For someone else it may overreach. You ran a 3:24, but I would say, with marathon specific training you could have popped off a 3:03. By foregoing the marathon specific speedwork that specifically raises LT you traded off maximal aerobic speed for long-term endurance. You raised LT and VO2max through strict lowHR, but eventually you have to do real speedwork to maximize for a specific distance. I think that you would have had a hard time do 3 back to back marathons if you didn't emphasize the endurance aspect.

Unfortunately, the MAF predicted 5k chart is as opaque as his formula. Anyway, like I said, just me making something simple complicated.

--jm

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posted Feb-17-2006 05:35 AM               

quote:

---

Originally posted by junkmiles:
You didn't miscalculate, but I was just speculating that extending the MAF predicted 5K out to marathon distance via mcmillan will under or over estimate. MAF pace must correlate to a training pace as defined by Mcmillan. In most cases, I assumed this would be recovery or easy run paces.

Let me explain my thinking step-by-step.

I take the MAF HR and place it context of traditional training zones (based on maxHR). I do this only because, that is how Mcmillan defines his training zones. I don't think it is unreasonable, since MAF is just an alternate, if opaque, method to define aerobic zones. It is not a different physiological theory. Also, mcmillan assumes (as it must) that a runner is properly trained for the given distance and is aerobically fit. This means there is a strong correlation between all race paces, as well as training paces.

--jm

---

Ok, now I understand - basically, you are assuming MAF to equate
to "easy training pace" whether by McMillan's, Maffetone's or
whoever's definition. That explains the discrepency. Just to be
clear, even if I am using Maffetone's MAF-5, the table I provided
earlier refers to
the actual MAF value computed by Maffetone's equation (so if
one were to always run at MAF-10 or something, they'd have to
run at least one run close to the actual MAF definition to make
the least conservative guess). There's no doubt that McMillan's
training paces, even the easy ones, are much faster than you
would generally get following Maffetone's approach and are
more inline with Pfitzinger's (with the exception of some of the
very experienced endurance runners with a well-established
aerobic base - many of them run probably half of their runs
at far lower heart rates than MAF.) I think you and I disagree on one
part, which is whether McMillan's race predictor is highly dependent
on following his training paces. I don't think it is. Using my
last marathon as an example, while I probably ran it way under
capacity, given how many long races I had run in the weeks
before (especially the 50 miler one week earlier), it's expected
that I couldn't peak my performance. Further, at the time, I
just had no idea what I was capable of, so I was very conservative
as a consequence. I finished the race with a smile and plenty
left in the tank, and without any sign of glycogen depletion, which for a
marathon, indicates that I was running far under capacity. Given
how well it went though, I'm not sure I wouldn't choose that approach
from here on in!

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posted Feb-17-2006 07:50 AM               

My good friend has been running 16 miles per week using low HR training for about 10 weeks. For the first 8 weeks, she was seeing no improvement. Staying at 4.8-4.9 on the TM for the whole 6 weeks to keep under MAF.

She would run 4 days a week for 4 miles.

Since she doesn't really want to increase her weekly mileage just yet, I suggested that she make one day a week a 3 miler, and the other a 5 miler. Keeping to her usual heart rate performance this allowed her to go a little faster on the 3 miler, and the 5 miler stretched her endurance a bit. 2 weeks later, she's running 5.0-5.2. It sort of bumped her system off the plateau, and she's making some progress.

So, perhaps there are ways to arrange a low-mileage plan that will challenge the muscles out of their lethargy.

--Jimmy

My Running World
My Maffetone Low-HR Training Experiment

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posted Feb-17-2006 09:13 AM            

quote:

---

Originally posted by leitnerj:
I finished the race with a smile and plenty
left in the tank, and without any sign of glycogen depletion, which for a marathon, indicates that I was running far under capacity. Given how well it went though, I'm not sure I wouldn't choose that approach from here on in!

---

I don't think we disagree at all. Mcmillan's calculator implies a strong correlation, not necessarily a strong dependence. I think aerobic fitness doesn't just apply to race pace performance, but also training as well. I'm not saying you have to train according to mcmillan's training paces to acheive his predicted times. I'm saying if you are aerobically fit, then you could run those paces at the corresponding intensities, not that you have to run those paces. You showed that yourself, because you got within spitting distance of a potential peak marathon performance on just lowHR training and within a 2 month period of intense endurance racing.

Isn't that the whole point of lowHR training, whether maffetone or not. If you can blaze a 5K, but your marathon performance doesn't match up, I would predict that your 'easy' training pace occurs at too high an intensity. It's just the other side of the coin of being aerobically unfit.

I would say though that your potential single marathon peak performance is probably more in line with my interpretation of MAF pace. I don't think you could have pulled off the 50miler and 3 back-to-back marathons as well as you did if you had done Maffetone as base building and then followed a more conventional marathon plan aimed at peaking for one race.

On your last statement above: I'm looking forward to that experience myself in the fall.

--jm

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posted Feb-17-2006 09:29 AM            

quote:

---

Originally posted by jjwaverly42:
For the low mileage runners:

My good friend has been running 16 miles per week using low HR training for about 10 weeks. For the first 8 weeks, she was seeing no improvement. Staying at 4.8-4.9 on the TM for the whole 6 weeks to keep under MAF.

She would run 4 days a week for 4 miles.

So, perhaps there are ways to arrange a low-mileage plan that will challenge the muscles out of their lethargy.

--Jimmy

---

Jimmy,

This is excellent advice. Nice to see a real world example for folks to apply to their own situation.

The body will adapt relatively quickly to a schedule of equivalent mileage everyday. Variation is the key, whether high or low mileage. A 50mpw runner, doing 10miles everyday for 5 days would eventually run into the same issues as your friend.

You often reference the Team Oregon folks and I think their plan that shows ratios of daily runs provides a good model for getting variation into a weekly running schedule, no matter your weekly mileage. Whether you run 2,3,4,5 6 or 7 days you should be working towards (or close to) the ratios (1:2:3) for short, medium and long runs. Obviously, a person might have to work up to being able to actually do this, but your friend switching over to 3mi & 5mi (1:1.67) is a good start. As she adds mileage and days she'll eventually work close to 1:2:3.

This can be done by time or mileage, which ever is easier. I prefer time, since it keeps you from outrunning your own fitness level.

--jm

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posted Feb-17-2006 09:47 PM            

Yes I am slower than a turtle running through peanut butter.

Jan 9, 2006 16:00
Jan 16, 2006 15:19
Jan 23, 2006 14:31
Jan 30, 2006 13:50
Feb 6, 2006 13:31
Feb 13, 2006 13:23

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posted Feb-17-2006 09:55 PM               

quote:

---

Originally posted by Cashmason:
My progress at Maf - 5 for last 6 weeks. Averaging 40 miles per week.

Yes I am slower than a turtle running through peanut butter.

Jan 9, 2006 16:00
Jan 16, 2006 15:19
Jan 23, 2006 14:31
Jan 30, 2006 13:50
Feb 6, 2006 13:31
Feb 13, 2006 13:23

---

It's all relative. And 2.5 minutes per mile improvement in
just over a month is phenomenal. Your next marathon will
be a much happier one!

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posted Feb-17-2006 10:27 PM            

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posted Feb-17-2006 10:27 PM               

quote:

---

Originally posted by Cashmason:
My progress at Maf - 5 for last 6 weeks. Averaging 40 miles per week.

Yes I am slower than a turtle running through peanut butter.

Jan 9, 2006 16:00
Jan 16, 2006 15:19
Jan 23, 2006 14:31
Jan 30, 2006 13:50
Feb 6, 2006 13:31
Feb 13, 2006 13:23

---

16% improvement in 5 weeks. Awesome. Great job.
Keep going.

--Jimmy

My Running World
My Maffetone Low-HR Training Experiment

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posted Feb-18-2006 03:48 PM               

I ran at Maff /Maff-3 for approx. 11 weeks.

Saw improvement quickly i.e. was able to improve pace at Maff HR and then dropped Maff to -3 and pace stayed the same. This occurred over approx. the first 6 weeks. Got a cold and all heck broke loose. My pace plummented for 2 weeks. Saw pace improvement for the next 1.5 weeks after the 2 week cold period, though I never got back to where I was prior to cold. Then pace started to get slower again. For the last 1.5 weeks I saw a small, but slow decline in performance. I decided I may be done with Maff for now. I performed another 5 mile track test under better conditions than the first test and results were slower.

I decided to move to Pfizenger marathon training program and use those HR zones. Ran 2 easy runs and then had a 20 mile long run yesterday. Ran the 20 miler at a HR 137-150. I started the run low and ended at 150. It was warm (53 degrees) and very windy (gusts up to 40 mph). I still had to keep the pace slower than comfortable to stay under 150. This surprised me since the HR was so much higher than Maff. Though the pace was slower than what I thought it should have been, I believe the wind had a great deal to do with it. I actually had to walk over a bridge because the wind was so strong. I had more stiffness in my hips and pelvic area than I thought I would, but I also realize it was still a 20 mile run.

This AM I was stiff enough to consider skipping the recovery run and take a day off, then thought I might be better off with the run than the day off. I walked for the first 100 yards or so and had no concern about pace. I simply wanted to keep HR low and loosen up. I was pleasantly shocked how good I felt. My HR was lower than it has been since prior to my cold. I kept checking HR Monitor to see if it was working properly. I kept getting readings in the low 120's and my pace was reasonably quick. My HR was slow to go up over the rolling hills. No effort whatsoever to keep HR low. Only ran 4 miles, but it was the best 4 miles in a long long time.

What's up with this? Has anybody else experienced something like this? Phenomenon or training payoff?

Karen

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posted Feb-18-2006 04:00 PM               

quote:

---

Originally posted by Ksabbo:

What's up with this? Has anybody else experienced something like this? Phenomenon or training payoff?

Karen

---

Whenever I have the time and the motivation to get up early
(sometimes at 3:30-4 am), I'll do back to back 20 milers on the
weekend. I'm always faster on the second one, even if my heart
rate crept up a lot at the end of the first. Even if you're going
5, 10, or even 15 or MAF, you're still well into the aerobic zone,
so you're still getting a nice aerobic workout and probably not
interfering at all with your basebuilding, especially if you've been
running below MAF for more than a couple of months as you
have. (After a couple of months, not only will your pace pick up
at the lower heart rates, but you will start to burn a higher percentage
of fat at higher heart rates - at least that's my belief anyway!)

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posted Feb-19-2006 06:46 PM               

7:26/155, 7:16/159, 7:36/165, 7:42/165, 7:36/164,
8:02/164, 7:22/165, 7:56/164, 8:02/165, 7:46/163,
7:48/163, 8:18/164, 8:13/164, 8:07/164, 8:17/163,
8:30/165, 8:31/164, 8:23/162, 8:18/166, 8:25/166,
8:06/169, 8:12/170, 8:17/170, 8:57/168, 8:35/166,
9:14/169, 3:25(7:13/mi)/172

The 9:14 mile was all a steep uphill and I was happy to do
that!

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posted Feb-19-2006 07:04 PM               

--Jimmy

My Running World
My Maffetone Low-HR Training Experiment

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posted Feb-19-2006 07:09 PM               

quote:

---

Originally posted by jjwaverly42:
Nice run, Jesse. So, do you feel the no-gel plan was a success?

--Jimmy

My Running World
My Maffetone Low-HR Training Experiment

---

Given that I never experienced the "low on glycogen" feeling that
I used to know so well, I feel that the use of gels would have been
irrelevant. Could certainly have been a different story had I been
pushing myself hard, say 30-45 sec/mile faster. By the way, I'm
definitely not saying that gels are the devil or anything, but just that
you can train yourself well to run a fairly decent race on mostly fat.
I would certainly probably take them if I were targeting an "excessive"
PR or running an ironman or ultra.

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posted Feb-19-2006 07:09 PM               

--Jimmy

My Running World
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posted Feb-20-2006 08:53 AM               

Anyway, my long run went lke this:

1)...12:58... 103
2)...11:51... 117
3)...11:44... 122
4)...11:32... 125
5)...11:32... 127
6)...11:32... 127
7)...11:32... 128
8)...11:32... 131
9)...11:32... 130
10)...11:32... 130
11)...11:32... 133
12)...11:32... 137
13)...11:32... 139
14)...11:55... 140 ate 1/2 a zone bar
15)...12:48... 140
16)...13:12... 140
17)...13:05... 140
18)...14:03... 141 2 wb's to keep HR down

21:00 Cooldown 2.8

I forget to pick up sports drink, so I just drank water and had a half a zone bar at the beginning of mile 14. I don't know if it's a coincidence, or if that was when my HR drift kicked in, but after I ate that bar, my HR started rising rapidly.

Does anyone have any data or ideas about the effect of eating during a run--does it somehow take your body out of fat-burning mode?

All I could think of when I ate at that point was Slow Burn and how he doesn't take nutrition during a marathon.

Also, if I were to do a speed that allowed my hr to go to 10 beats over my MAF of 141 (i.e. 151 bpm) to adjust for heart rate drift, would my body start to burn more sugar as my HR rose over my MAF? Since the rise in HR has nothing to do with fuel at that point, but the blood starting to dehydrate a bit. I'm just curious what ya think about that.

--Jimmy

My Running World
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posted Feb-20-2006 09:29 AM               

Jesse,
What formula did you use to target HR 165?

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posted Feb-20-2006 09:41 AM               

quote:

---

Originally posted by jjwaverly42:

Does anyone have any data or ideas about the effect of eating during a run--does it somehow take your body out of fat-burning mode?

All I could think of when I ate at that point was Slow Burn and how he doesn't take nutrition during a marathon.

Also, if I were to do a speed that allowed my hr to go to 10 beats over my MAF of 141 (i.e. 151 bpm) to adjust for heart rate drift, would my body start to burn more sugar as my HR rose over my MAF? Since the rise in HR has nothing to do with fuel at that point, but the blood starting to dehydrate a bit. I'm just curious what ya think about that.

--Jimmy

My Running World
My Maffetone Low-HR Training Experiment

---

This will be surprising to hear from me, Mr. "no carbs during a training
run" (even soon to be Mr. "no carbs during a marathon") but I don't think
that taking in the carbs late in the run has any effect on using fat vs
carb for fuel, and certainly not on causing your heart rate to rise. What
you are seeing is very consistent with what I've noticed. For my first
few 15+ mile runs in a "training" series, there's a magic point, generally
around 15 miles for me, where my heart rate really starts to climb. Late
in the season it does not do that. I can make my guess and assume that
it's accumulation of lactic acid (later in the season, I assume you become
more efficient at flushing the small quantities that build up during a low
intensity run, but earlier in the season, more seems to accumulate than
not). You'll probably see this same effect during your next several long
runs. Try taking your zone bar at mile 10 and I'll bet you see no effect.
By the way, I noticed a couple of months ago that any time I burp while
running, my heart rate drops by about 5-10 beats for a good 8 seconds
or so. I was hoping that burping might be encouraging a more efficient
fat burning (in which case, I'll start planting Cokes around my running
courses), but alas, after the 8 seconds, I return to the original steady
state!

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posted Feb-20-2006 10:00 AM               

quote:

---

Originally posted by crb81:
In my previous marathon I
reset my target HR to 5-7 beats higher for most of the second half,
but this time since I was running with a friend for a while, I waited
until much later. Here are the splits

Jesse,
What formula did you use to target HR 165?

---

A very good question and you may be surprised at my answer,
given how I push the MAF formula. While you can go to something
like the Oregon pace wizard, I think the best way to find a target
heart rate is by experimentation and not by a formula. Nonetheless,
I do take into account some factoids that I've gathered. My actual
MAF pace is 144 (assuming I don't add or subtract 5). My anaerobic
threshold is ~ 179 (so I need to be a good bit under that). My max
heart rate is 210 (so if I use some % of that, I'll be way out of whack
since my AT is so much lower). Now, without regard to any of that
stuff, I think for most people the first 1/2 - 2/3 of the marathon should
be run at a "comfortably challenging" pace. Now isn't that ambiguous?
(If you are not well-developed aerobically, a comfortably challenging
pace will slam you into the wall at mile 19 or 20. ) The last 1/2 to 1/3
(really based on how much experiences you have with marathons)
should then be run at a "less comfortable, but slightly more challenging,
pace." (This "new" pace might actually be a little bit slower than your
pace in the first 1/2 to 1/3, especially if it's hot out, due to heart rate
drift.) So, in the first few miles of the marathon, I try to find this pace
where my heart rate remains fairly steady, I'm well below threshold,
but I feel challenged. In my marathon in November, when I was in
much better shape, I used about 162-163 to start and 167-170 later.
Yesterday, I used about 165 to start and 168-171 later. If I were
targeting a peak performance race, I would use about 4 beats higher.
One of the benefits you get out of MAF training is that, although you
spend most or all of your time below MAF, you really tend to learn
your body at a large range of aerobic heart rates and you become
must less sensitive to things such as poor pacing and so forth, i.e.,
you can make your running much more robust.

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posted Feb-20-2006 10:04 AM               

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posted Feb-20-2006 01:03 PM               

quote:

---

Originally posted by Jim Sullivan:
[QUOTE]Originally posted by leitnerj:
[b]

I take in carbs before a race or a long run, as I've done them both with and without carbs, and I run better after the carbs. That's the only thing that matters.

---

i tend to fall somewhat in this category, I'll carb (complex) 90 mins before and do water only. Then right before I'll do a gel, do another gel around 1/2 and 20 miles.

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posted Feb-20-2006 08:42 PM            

quote:

---

Originally posted by jjwaverly42:

Does anyone have any data or ideas about the effect of eating during a run--does it somehow take your body out of fat-burning mode?

All I could think of when I ate at that point was Slow Burn and how he doesn't take nutrition during a marathon.

Also, if I were to do a speed that allowed my hr to go to 10 beats over my MAF of 141 (i.e. 151 bpm) to adjust for heart rate drift, would my body start to burn more sugar as my HR rose over my MAF? Since the rise in HR has nothing to do with fuel at that point, but the blood starting to dehydrate a bit. I'm just curious what ya think about that.

---

My understanding of carb intake during exercise is that it does not cause the same insulin response if consumed before exercise. Insulin interferes with the metabolism of fat, but, as I said, it doesn't appear to spike as much during exercise. This is probably particularly true after the fat burning cycle has fully kicked in, which is at least 20-30min after starting moderately intense exercise. So, I agree with Jesse, it probably wasn't the zone bar.

I think you hint at this in your question: HR is a proxy for effort, it is not the 'thing' that determines whether or not you are anaerobic or not. How hard your muscles are working determines that. However, I suppose, at late stages of a long run, the same inefficiencies that cause cardiac drift might cause your working muscles to slip into slightly more anaerobic state than before. That's a guess on my part; a check of a reliable physiology text will confirm or not.

Remember, even at relatively low efforts as may be defined by a MAF HR, your body is still using some small, but non-zero, anaerobic energy production. I believe, in your case, you have to maintain an HR of about 120 or so to stay absolutely, totally aerobic.

--jm

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posted Feb-20-2006 09:39 PM               

quote:

---

Originally posted by junkmiles:
My understanding of carb intake during exercise is that it does not cause the same insulin response if consumed before exercise. Insulin interferes with the metabolism of fat, but, as I said, it doesn't appear to spike as much during exercise. This is probably particularly true after the fat burning cycle has fully kicked in, which is at least 20-30min after starting moderately intense exercise. So, I agree with Jesse, it probably wasn't the zone bar.

I think you hint at this in your question: HR is a proxy for effort, it is not the 'thing' that determines whether or not you are anaerobic or not. How hard your muscles are working determines that. However, I suppose, at late stages of a long run, the same inefficiencies that cause cardiac drift might cause your working muscles to slip into slightly more anaerobic state than before. That's a guess on my part; a check of a reliable physiology text will confirm or not.

Remember, even at relatively low efforts as may be defined by a MAF HR, your body is still using some small, but non-zero, anaerobic energy production. I believe, in your case, you have to maintain an HR of about 120 or so to stay absolutely, totally aerobic.

--jm

---

I do know that as the slow twitch fibers begin to become exhausted in the latter part of long runs, the muscles will recruit fast twitch fibers, which is another reason why you can ultimately get faster from long runs. The sharp decline at mile 14 in my long run is certainly a measure of my current aerobic endurance. I must have been recruiting those sugar burning fast twitch fiber at that point. And as Jesse said, I was building lactate. A sharp rise in HR after 13 miles of a slow rise indicates that.

How did you come up with 120? That's about 60% MHR for me. Even if it is my pure aerobic zone, I'm not going to train at that HR, and you can't make me! Please don't make me...
:> )

--Jimmy

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