Archive for October, 2011

Worries

October 30, 2011

Every marathon has its worries.

This year I am worried because of my past (relatively speaking) failures. So far, the wall has always crashed down on me at some point in the race (last year I knew by mile 10 that I had failed again, the time before that it was closer to mile 19).

Maybe if I carbo-load differently. Maybe if I eat a small amount every mile. Perhaps I need more salt during the race?

I don’t know.

The trouble with fueling for the marathon is that there’s no good way to test. You have to actually race a marathon for the test to be valid, and I can do that, at best, twice a year (assuming no injuries). I need time to recuperate afterward, and then 3 months to train before the next. There may not be enough marathons left in my life to figure out how to eat for one. I could certainly jog through lots of slower marathons, say  3:30 or so, but I wouldn’t need to fuel and so the test wouldn’t be meaningful. So all I can do is try something(s) different from the last times and hope.

My other big worry on this race is THE HILL¹. I’m not really worried about running up it too slowly (though I am a bit), there’s also the worry that I might go up too fast, and ending up at the top with absolutely no energy left and another 2.5 miles to go.

I expect I’ll go up THE HILL at about an 8minute pace. That means I’ll lose about 35~40 seconds off the 6:50 pace I want to average (THE HILL is about half a mile). 35 seconds isn’t too hard to make up. I want to do it before I reach THE HILL as there isn’t much time afterward. I may be able to run 6:30s on the downhill after it, but I don’t want to depend on it…

And there is a certain sadness involved in this race. In the past I have striven to break 2:55, but I’m giving that up now. This year I just want to break 3. I think I’m too old to break 2:55 now (for me to break it, I mean. Better runners can at my age). Ah well.

Dress Rehearsal

October 22, 2011

And it came to pass in those days, that there went out a decree from Caesar Rusticus, that all the world should be dressed — in uniforms. And all went to be photographed, every one into city college. I had intended to break in my new shoes for the marathon, so I had new shoes on too. It was our longest training run, 23 miles, 13 of them at marathon pace, and we were to finish at the marathon finish (more or less).

As close as we’ll get to a dress rehearsal.

Mike tells me to run at a 6:40 pace.

I live just at the bottom of the HILL¹ and planned to run from home to where everyone was meeting — which was the finish area. We’d warm up there, then start, running backwards to mile 19.5, turn around and run to the finish. Then I’d run home.

It was still dark when I poked my nose out the door a little after six. Dark and very, very foggy. The HILL isn’t really that bad when you aren’t trying to go fast. It’s kind of fun to be out there when there’s no one else on the road and just the faintest of light from the intersection at the bottom.

Today was the day of the SB bike century. I hadn’t connected that with what we were doing, but when I got down to Leadbetter I found lots of people, bikes and bright lights. So our group was a little further down the beach from our usual spot.

A forty minute warmup after my 3 mile run to the start meant about 8 miles total (and so the run home would be just the right amount to finish off the day). Then we all trooped across the street to have a picture taken. There are a lot of us today. It’s still foggy, but almost light enough to take a good picture…

Finally we started. We’re now climbing the backside of the HILL; this climb is spread over 2 miles (rather than half a mile) but it’s just as high and seems to go on forever. We thought to go up at a 6:50 pace. Halfway up I realized my shoelace had come untied so I had to stop and tie it up again. This put me behind everyone else in my group, more like a 7 minute pace for me.

Ah well.

My glasses were fogging up too. They’d been OK when I was running easily, but now I’m running harder I can’t see. I have to keep wiping them.

But now it’s downhill for a bit and I run at a 6:12 pace as I try to catch up with my little group.

I don’t. They are going fast too.

Then it’s another slow grind of a climb this time it takes 3 miles to get up to the same height, so it’s not quite as slow… 6:33, 6:46, 6:41.

And then… half a mile or so of downhill, but the sad thing about this one is that we turn round at the bottom and have to go back up the wretched thing again. Average pace 6:44. Not good. I’m going slowly today. I didn’t feel that tired when I started out.

But I guess I am.

Hmm. Kary seems to be going slowly too. I’m actually catching up to her on a 6:37 mile. But when I reach her she announces that her shoe is untied and stops to fix it. Leaving me running after the dimly perceived figure of Eric, off in the fog in front.

Kary passes me again (of course).

I finally give up on my glasses. I can’t seem to wipe them clean any more. I just hold them in my hand. The world is much clearer now. Even my vision is better than foggy glasses☺.

And now it’s down Los Positas. This should be easy, but after a mile I see I’m doing 6:46. Very ug. I try to speed up, but the next mile isn’t much better. 6:41. OK, I’m supposed to be running 6:40s, so 6:41 isn’t bad but this is a downhill mile. I should be going faster because I know I’ll slow down even more on the HILL.

Which now lies before me.

The SB century also ends with this hill, and they’ve placed a happy little sign for us: One last little hill ☺

They’ve climbed ~9000ft in their 100 miles, while we’ve done perhaps a tenth that. It’s much more significant for us. It doesn’t feel little. At all. At all.

Two weeks ago I charged right up this thing at a 7:00 pace. Today I’m slow. I know it. Of course I’ve now run 10 miles while when I faced this hill two weeks ago I had run 3. That makes some difference, but it’s more that I’m just tired now.

I go up, as best I can, and at the top I see I ran a little faster than 8 minute pace for the half mile hill. I’ll probably be at least this tired when I face it in the marathon for real. The rest of the mile is almost back on track though, at a 6:46 pace.

And then it’s a glorious downhill run. Remembering Los Positas I’m a little nervous, but I don’t need to be. I run a 6:25 and a 6:23.

And my average pace was 6:41. In spite of everything. Even including my shoelace. Good. I hope that means I can run 6:50s on marathon day…

(And then I ran home exceedingly slowly).

How color-blind people see the world. Maybe.

October 13, 2011

I’m frequently asked this. But how can I answer?

The first thing to note is that we aren’t really color-blind, we just get a little mixed up about red and green. And, yes, we do see red and green; we just see them differently than you do.

Can I see the colors in stop-lights? (is it safe for me to drive?)

Yes, I can see three different colors in a stop-light. The “green” light doesn’t look green to me, it looks almost white, but that’s irrelevant, all three colors are easily distinguishable and that’s what matters. (Also, the order of lights in the stop-light is fixed. World-wide as far as I can tell. Even if I couldn’t see colors I could remember: If the bottom light is on: Go. If the top light is on: Stop.)

Most of us aren’t blind to colors, but there are a few people with no color vision at all. No cones in the eye, just rods. They don’t see well in the daylight, nor do they have very fine-grained vision. This is very rare, but it does happen. I shan’t be talking about them, but it’s fairly easy to answer for them (I think). Their world is black/grey/white. The daytime is too bright and it’s hard for them to see at all then. Their vision is fuzzy at the best of times.

What is color?

Color is a trick our minds play on us. It is vaguely related to the wavelength of light, but not precisely.

A given wavelength of visible light can be assigned a color, but the reverse is not true. There are many colors that do no appear on the spectrum. Magenta. Brown. These colors are made up of several different wavelengths (or their lacks) and combined in the mind to produce a single thing called “color”.

The history of color vision

Many years ago, probably a little before the Cambrian explosion (or 530 million years BP), the eye evolved.

Early eyes were simple. Just a light sensor. But over time they became more complex and gained sensors for multiple wavelengths, lenses for focusing and brains for processing.

As early as 500my BP color sensors (the cones) had differentiated from the early light sensors (the rods). Both were useful, rods respond well at low levels of light but provide no color information, while cones need high levels but do provide color data.

Birds, reptiles and teleost fish mostly have four color sensors in their eyes (as well as the rod light sensors which I’ll now ignore).

True mammals evolved about 200 million years ago, presumably with the full 4-sensor complement of other tetrapods, but they were nocturnal and burrowing animals. They couldn’t use color vision, and their eyes degenerated to 2-color (blue-green). About 40 million years ago a mutation in the old-world monkey line duplicated the green sensor gene, and the products of two genes (the original and the duplicate) diverged to give monkeys the 3-color vision we are familiar with today.

This change was so important that there are no old-world monkeys left with 2-color vision. There are also, essentially, no monkeys who are color-blind. Color-blind monkeys take too long to find good food and slowly starve and die.

Humans don’t have the same selection pressure on them that monkeys do. It’s much easier to find ripe (red) fruit in a supermarket than in a tree, so humans are slowly losing the sensitivity of their red sensor. About 8% of Caucasian males are color-blind.

Our red and green sensors (and those of all other old-world primates) are 98% similar in their amino acid sequence (there are either 15 or 16 different amino acids between the two). The green sensor responds best to 530~535 nanometer wavelengths, and the red to 560~565nm. Although there are ~16 differences, only 7 are functional, and of those 7 differences, one in particular accounts for a 14nm difference in sensitivity peak (almost half the total wavelength difference), another for 7nm and a third for 4nm.


Sensor response in normal 3 color vision
The plot labeled “S” is for short-wavelength light (blue)
That labeled “M” is for medium-wavelength light (green)
That labeled “L” is for long-wavelength light (reddish)
From WikiMedia Commons

So there are seven possible single point mutations that can cause some level of color-blindness, and many more (127) multiple point mutations. But the result of any of these changes is that the red sensor moves closer to the green sensor and the ability to distinguish between red and green drops. The amount of movement will vary depending on which mutation(s) occur.

How do we represent photographs on a computer?

Back in the nineteenth century people worked out that most colors could be represented by a mixture of three primary colors (sometimes additive primaries are used: red, green, blue; sometimes subtractive primaries: magenta, cyan, yellow). Color photography is based on this idea.

In a computer every pixel of an image is represented as a percentage of full red, of full green, and of full blue. The same is true of a television signal. Computer monitors and color TV screens are similar: every dot we think we see is actually made up of three small dots close together, one red, one green, and one blue.

Oddly enough there is no standard fixing what red, green and blue are. So two different monitors might display the same image slightly differently, and an photographic image on a monitor might look different from the original.

You might think that everyone would want to use the peaks of the three color sensors in the eye. Go back and look at the image above for a moment. The peak for the long wavelength sensor is nowhere near red, it’s greenish. We can only represent colors that lie between (on the spectrum) the two extreme colors. If we used that greenish peak as the basis for our monitors we would never be able to represent any reds at all.

On the other hand if we use a color which is too far from the peak, then we’d never be able to display a bright red, simply because our eyes would only respond dimly to the color we chose.

So a compromise is used, and people generally choose a color that is about half-way down from the long-wavelength peak.

How do color-blind people see pictures on the computer?

This is a much simpler question, but it is still basically unanswerable. The best I can do is talk about what basic color sensor outputs in the eye might be like.

When talking about the real world we’d need to worry about how the color-blind eye would respond differently to lots of different wavelengths, but when talking about an image displayed on a computer monitor all we need to do is worry about how the eye responds to the three wavelengths used in the image. Red, green and blue.

We don’t know exactly what shades of red, green or blue will be used but the general idea can be conveyed even if we don’t know the specifics.

The blue color will look basically the same to a normal and a color-blind person. (the blue curve doesn’t shift, and the long-wavelength curve barely intersects it).

But for a color-blind person the long-wavelength (red-most, but not really red) sensor peak in the eye moves closer to the green peak. This means that for green light the long-wavelength sensor will be a little more responsive than for normal people (so green light will appear slightly brighter and perhaps redder) while for red light the sensor will be a lot less responsive (so red light will appear much dimmer and less red).


Here I have taken the cone response curve from above and superimposed a black line representing a the long-wavelength sensor for a color-blind person. Vaguely. Again, each color-blind person is different. I’ve chosen a spot midway between the medium and long sensors of a normal eye (remember a single amino acid change can cause 14nm movement so this is a reasonable value).

Note that this sensor now responds a bit more vigorously to green (shown by the dark blue arrow under the green peak) and a lot less vigorously to red (shown by the light blue arrow in the red area).

When the green of your monitor enters your eye you get a strong response from both the “M” (green) and “L” (sort of reddish) sensors. The “L” sensor responds with about 91% of its peak value. For a normal eye. For a color-blind eye the “L” sensor will respond with about 96% of its peak. So for a green signal, the red sensor of a color-blind eye will see an increase by 5% of the green value.

When the red of your monitor enters your eye you get a 50% response from your “L” sensor. While a color blind eye will get about 33% from its “L” sensor. So the color-blind eye will see red at 2/3 of the level seen by a normal eye.

So if I were to take a normal RGB photograph, and decrease the red to 2/3s and then increase it by 5% of the green sensor’s reading it might provide you some idea of what I see.

normal adjusted

Here is a card from the Ishihara Color-blindness test. If I’ve done things properly the card on the right will be just a bunch of spots. (I, of course, can’t tell. Both images look like a bunch of spots to me).

My friend Greg tells me he can easily see the digits in the color-blindness test even after the transformation, and points out that power is proportional to the square of the intensity of incident light, and therefore suggests that the ratios above should be squared (so red=(2/3)^2 * red + (1.05^2-1)*green).

normal adjusted

I wondered if it might be possible to perform the reverse transformation so that I might see what everyone else does. There turns out to be a major problem with this though, red needs a much greater dynamic range than it actually has (it needs to go from -5% to 150% instead of 0-100%). None the less, I tried to apply this to the color-blindness test above. It didn’t work (the test still looked like random dots), however it did run up against the dynamic range issue — so I don’t know if it didn’t work because the ideas are wrong, or if it didn’t work because I could not do a real de-color-blindness transformation.

I don’t really know if I’m doing anything reasonable here. I’ve managed to convince myself that there is something to my argument… but… I don’t really know…

Kary said

October 8, 2011

she was going to run 6:45min/mile pace.

I didn’t believe her for a minute, of course. But since I wanted to run about 6:35 I foolishly hoped that she might run at my pace.

Today we were starting a little after mile 19 and running to somewhat more after mile 23.5 and then turning around and coming back. This is a challenge because between miles 23 and 23.5 lies the HILL we all dread. In this half mile we climb ~200ft, from sea-level to the top of the Mesa. That doesn’t sound bad. It’s a 3%+ grade. But if you try to run up it fast it turns out to be really hard.

Rusty exhorted us to drink at the turnaround, then started all the slower groups each in order, and then he went off and tried to talk Kent into running with Drea. We seemed forgotten. After a bit Kary said “Go!” and we went. Kary’s watch seemed to be working today, after a bit she turned to me and said her watch showed a 7min pace, and asked if that’s what mine showed. Mine said 7:04. Kary went a little faster.

Then Kent caught up with us, when I asked he said he felt tired and not up to running with Drea today. He, in turn, asked what our pace was and Kary said “6:45”. Well, we got to the 20 mile mark with an average pace of 6:33 (which was just what I wanted, so I was pleased).

Jeff and Rob seemed intent on really doing 6:45s and dropped back from the three of us early on.

The next mile marker had been erased when they resurfaced the road, but I knew roughly where it was. I clicked my watch, but didn’t look at it. I see now we were running at a 6:24 pace.

Then a nice little dip, and back up to Los Positas. Loud footsteps behind. Ricky, Kurt and Tim come zipping past. When I looked at my watch it said 6:07. Glump. That’s too fast for me, so I drop back from Kent and Kary.

The road here is full of runners, and they are also moving fairly fast. Even though I’ve slowed I’m so excited to be passing people that I haven’t slowed much. My watch now reads 6:08.

Marcello passes me.

Drea and Rusty pass me. And then pass Kary and Kent. Except Rusty hangs around a bit to talk to Kary.

The 22 mile mark is also gone, but is somewhere near Veronica Springs. A 6:12 pace. Mostly downhill, of course.

Fewer people to pass now. Kary and Kent are far ahead. Finally I approach the group that started just before us. The last people I shall pass. They aren’t going much slower than I and I run behind them for a long time.

The 23 mile mark vanished too, but is somewhere near the bottom of the HILL. So I click my watch (6:14. Damn it how fast are the “slower” guys going?).

I’m interested to see how fast (or rather, at what pace) I can climb the HILL, so having the mile mark at its base is convenient.

I push myself, and, slowly, gradually, I catch up with and pass Joy, and Dan and Jim. And then I’m through them. It’s still a long way to the top though and I have to keep pushing even without having anyone to overtake. (Kent and Kary are way up there, I’m not going to pass them).

The top arrives (6:56 pace. Mmm. not bad. of course I shan’t be able to go that fast on race day, but not bad for today).

The top arrives, but I can’t stop, there’s still another 1/3rd of a mile to go before the turn-around. Interestingly enough I manage to speed up again and run it at a 6:21 pace. Shan’t do that race day either.

Kary just turns and comes back. She doesn’t get water. Kent does. I want water.

I turn off my watch, and then rummage in the truck for my water bottle. It seems to take forever to find my bottle among the 50 odd other bottles in the truck. Finally I do, and drink.

Kent is off, as are Jim and Joy and a number of other people I’ve already passed. They are better at finding their bottles, I guess, or maybe didn’t try.

And I’m off. Going back along what I’ve already run. Turn on the watch again and fly down the hill. Lot’s of people still coming up. I catch Jim and Joy and Dan. On after Kent and Jerry (didn’t expect Jerry to be that fast). Three quarters of a mile, downhill, run at a 6 minute pace.

Click the watch again at Los Positas.

And now begins the slow slog uphill. It’s not like the HILL, of course. It’s just a 3 mile climb back up 200ft. It’s hard. It’s long. But it’s close enough to level that you don’t feel you have a right to slow.

I pass Jerry.

Kent is maybe 20ft ahead still. Kary is off in the distance — visible, but out of reach.

At the Veronica Springs invisible mile marker I click my watch. 6:40 pace. Yeah. Sort of expected.

And I’m slowly catching Kent. Odd. I don’t usually do that, he’s faster than I now-a-days. No wonder he didn’t want to run with Drea. He really must be tired. I pass him at the intersection Los Positas and Modoc. Now it’s downhill for a bit, and I expect he’ll pass me back, but he doesn’t.

Kary is off in the distance.

Up hill again. At the next invisible mile marker I see I’ve run at 6:38 pace.

There are two runners on the road who aren’t in Rusty’s group. Kary passes them. I pass them. And now the 20 mile mark. 6:34. Now that’s what I want to run. Not bad on an uphill mile after 7 previous miles.

And now, a somewhat bumpy but basically downhill mile lies in front of me. The last one. I hear feet behind me. It’s Kent. I guess I couldn’t stay ahead of him for long (my watch tells me I’m running at 6:14 pace, and he’s still passing me). Then Mike Swan follows him. I pick up the pace a little and continue to run a little behind them until

we are done. 6:10 pace.

And 6:26 pace for the whole thing. Wow. That’s fast for me.

(Reminder to self: Doing 6:26s for 9.4 miles in a workout does not mean I can run 6:26s for 26.2 miles in a race.)

Marathon Course Map

It was Kary’s idea

October 1, 2011

and I thought she was nuts.

Er. That is to say. I thought it would make the workout too hard for me.

Rusty and Mike have had us running around the marathon course. Two weeks ago we ran our marathon pace effort from the marathon start to mile 6. Last week from mile 5 to mile 12, and this week was to be from mile 12 to 20. Each week a mile longer. Each week further down the course.

Mike told me to run 20 miles today. (I wanted to run 21. He told me to do 20 last week too. I wanted something different:-)

On Thursday, as we were running together, Kary told me her idea. She wanted to start at mile 20 at 5:30AM and run back to 12 at 7 minute pace, then turn around and do a marathon pace (6:45) effort back. (When Kary says she wants to do a 6:45 pace she means she is going to run about a 6:25 pace. Or that’s what past experience tells me. — To be fair, when I say I want to run a 6:45 I end up running 6:35). This is about how Kary intends to run the marathon. Start out at 7:00 for 10 miles and then pick it up to 6:45. (or 6:25).

I thought that sounded too hard for a workout. 7 minute pace is close enough to marathon pace (indeed, I’ve never succeeded in running a marathon even at 7 minute pace) that I worried it would feel like a 16 mile marathon pace effort. And I didn’t think that would be wise.

On the other hand, essentially everyone else in my group was going to be joining Kary, and I didn’t want to be left out.

On the other foot, it meant starting at 5:30 in the pitchy dark.

On the final foot… I’ve been playing with eating a cliff shot block (30 cal) every mile of my marathon pace efforts (because I run out of fuel otherwise). It seems to be working, but this run would give a 16 mile test. Longer than I’d expect to get in the training cycle. Of course the real problems don’t come until mile 18 or 20, but at least I’ll know how I’d feel at 16.

So when I saw Rusty on Friday I asked him what he thought of the idea. To my surprise he seemed to think it good, and offered to bring water for us to the 12 mile mark.

Which meant I had to contact Kary and say I was coming.

And meant I had to show up at Vieja Valley school at 5:30. But VV is only at mile 19. So we jogged up to the 20 mile mark, stopped and chatted for a bit, and then we were off.

It was dark. But we all had flashlights or headlamps, and the course was flat. Running in the dark was not a problem; actually I found it kind of fun. There were 6 of us and we took up most of the lane running abreast. No cars were around. We did see a bike.

The first mile was 7:11. We’d intended to do the first a little slow, so that was good. The next was 7:01, 6:59.

Kary was bored, so she got Jeff to tell the story of a local robbery at the jewelry store run by a friend of ours. The friend’s husband came out of the back room with his shotgun and shot two of the would-be robbers while the other fled. I had no idea this had happened but the others knew.

Then we ran out of mile markers (repaved roads, and a slightly different course) the next 3.5 miles were run at an average pace of 6:51 (If I ran a marathon at 6:51, I’d be pretty happy, that’s just under a 3 hour marathon). The next two were even faster (I dropped back a bit from the others because I started to worry about going too fast, but I still averaged 6:48).

It was now 6:45AM. Sun was coming up, nice clouds on the horizon. We trotted down Fairview to the school. The rest of SBRR should have been around, but they weren’t. Kary had stashed some water for us here, (which was kind of her) and we got to drink at least. I had a gel pack.

Then we headed back up to the 12 mile mark, debating whether to wait for a common start (it’s more fun to start with the slow people in front, because then we get to pass them and say “Hi”, we all feel part of the same project).

We saw Mike. And Rusty. And then everybody else appeared. I got Mike to take my flashlight and gloves in the car — I wouldn’t need them any more. Rusty gave me some GU Brew (kind of him), and then they started the groups. Slowest first.

We debated how fast to go. Kary said she wanted to run at 6:45 since that was what she planned to do in the race. That seemed reasonable to me. In truth, I worried whether I’d be able to go even that fast — I’ve never tried an 8 mile MP effort after doing 8 miles barely slower than MP (well, I have on race day).

Our turn came.

Kary took off, and Eric with her. No 6:45s for them. I plodded along behind them at — oh. wow. 6:37 pace. Maybe this won’t be so bad after all. Rob passed me. Jessica passed me. Jeff started to pass me. He being the last of our group and I not wanting to run alone, I tried to talk him out of going quite so fast. He didn’t have a garmen and was surprised to hear how fast he was going (usually it takes a while to warm up to a pace, but we were already warm. Fast came too easily).

We trotted along, chatting.

Sometimes one of us would start to pull ahead, but the other would feel the change in pace and complain. We ran the first twoish miles at a 6:35 pace. Which is what I’ve been running all along. Perhaps I’m in better shape than I feared.

Then the long unmarked section. We passed Jessica (poor Jess has IT band issues or something). We ran these 3.5 miles at 6:34.

OK. That was easy enough. But… it was mostly downhill. Now we’re on the main UCSB bike path, and it’s all up hill from here.

6:30 pace. Jeff tells me he’s not going to keep up any more (what he means, is that he’s going to run about 6 feet behind me). 6:34 pace. We pass Rob, and he joins us. This last mile is the most up-hill mile of all. It’s not really steep, but it’s steep enough. I decide not to fight for the pace and let it drop down to a 6:40 (neither Jeff nor Rob passes me, so I guess they feel the same).

And here’s the 20 mile mark. We are done. Average pace 6:35.

So… I had no problems with the longer hard run. I had no problems with fuel either. It all worked.

I’m a lot more confident now than I was yesterday:-)

Trotted back to Vieja Valley, and there we met Drea and Tim, who race tomorrow.

Then everyone else left, but I had another 3 miles to do on my own.

But they weren’t bad.

Marathon Course Map