May 05, 2012

Marathon race pace strategy

This week I have been going back and forth on my pacing strategy for tomorrow's BMO Vancouver Marathon. The goal is clear: cross the finish in 2:59, which means running a pace of 4:15 per kilometre or 6:51 per mile.

Theoretically, there are different ways of getting there and success hinges on choosing optimal pacing for the individual runner on that particular course. While there are simple tried and tested guidelines, the two key variables—assuming that crazy conditions won't throw a spanner in the works and the forecast for tomorrow indicates excellent weather—mean finding the perfect pace varies per runner and per race. 

The art of marathon pacing is a skill that can take a while to master.

Advanced Marathoning, my training guide for the past 10 months, discusses the various strategies: running the first half hard and trying to hang on for the second half, aiming to run steady, i.e. the same time for the second as for the first half, and finally, a negative split in which you cover the second half faster than the first.

Initially I was going to aim for a negative split by starting at a 4:20K (6:58 mile) average pace in the first 10K and then slowly speeding up. But, looking at the halfway times in my marathons, I realized that I have rarely covered the second half faster than the first. 

And Advanced Marathoning says, "[The] basics of marathon physiology indicate that the best strategy is relatively even pacing... Most runners shouldn't try to run dead-even splits, however.

"... your running economy will tend to decrease slightly during the race, meaning that your lactate-threshold pace will decrease slightly as well. The result is that your optimal pace will be slightly reduced during the latter stages of the marathon," according to Advanced Marathoning.

"If you ran negative splits for the marathon (i.e., the second half faster than the first half), chances are that your run more slowly than optimally during the first half of the race and could have had a faster finishing time."

In my past 11 marathons, all of which I ran in 3:15 or faster, I have done a slight negative split three times. That was in the 2008 Victoria marathon, where I ran the first half in 93:37 and the second in 93:33; in the 2010 Rotterdam marathon, where I covered the first half in 96:06 (with a very frustrating first 5K) and the second in 95:45; and in the 2011 Vancouver Marathon where I ran the first half in 93:5X, and the second half also in 93:5X.
In my fastest marathon to date, 3:06:06, I ran an average 4:25 per K and 7:06 per mile. However, I covered the first 21.1K in 91:32, or an average 4:20 per K and 6:58 per mile. By 30K, I was still on track for the same average pace, reaching this point in 2:10:01. This was also the point where I began slowing down; I ended up covering the final 12.195K in 56:05, an average 4:35 per K and 7:24 per mile.

Why did I slow down? Was my 4:20 pace too fast and catching up to me in the final 12K? Did I 'lose it' mentally, not willing to take the pain needed to sustain the pace until the end? Or was the 3:09 marathon I had run only two weeks earlier the reason? I think it was a combination of those three factors, though I'll never know for sure.

I do know that it was the fastest I had reached the halfway point as well as the 30K mark in a marathon. Two weeks earlier I had run the first half of the Bellingham Bay Marathon in 92:02, my second-fastest first half; there, strong headwind was a clear reason for my slowing down in the second half to 97:38, while the first half had only marginally benefited from a tailwind.

(Check out the brutal impact of the headwind here: Split1 is the first half, Split2 is the second half. Overall Bellingham winner Uli Steidl won the searing 2012 Boston Marathon Top Master's title in 2:23:08.)

Having looked at my first half times for the past 11 marathons, I also looked at my splits for the second half. The fastest I did in Victoria in 2008 in 93:33 and the second-fastest was in Vancouver in 2011 in 93:5X (the official half times displayed in the results are incorrect so I am taking my watch split).

Marathon history (excluding my first 4 marathons of 4:18, 4:44, 3:24 and 3:36):

                                           Finish  1st half 2nd half
5. July 2006          Gold Coast   3:13:01   96:25   96:36
6. April 2007        Canberra       3:08:48   93:04   95:44
7. July 2007          Gold Coast   3:15:13   93:14 101:59
8. May 2008         Vancouver     3:12:56   93:17  99:39
9. Sept 2008         Victoria         3:07:10   93:37  93:33
10. May 2009        Vancouver    3:10:19    94:26  95:53
11. June 2009        NODM         3:10:39   92:53   97:44
12. April 2010        Rotterdam   3:11:51    96:06   95:45
13. May 2011        Vancouver    3:07:41    93:5X  93:5X
14. Sept 2011         Bellingham   3:09:40   92:02   97:38
15. October 2011   Victoria        3:06:06  91:23  95:42

Tomorrow, theoretically, I am aiming to reach the halfway mark in 89:59, 74 seconds faster than I ever have, and then hold on to do it again in the final 21.1K; that would be 3:34 faster than my fastest second half (from October 2008).

2012 BMO marathon course profile
If I want a chance of finishing in 2:59, I will have to commit to a 4:15 pace in the first half. Having said that, the profile is quite varied in the first 10K. It will be important to go by feel rather than time, conserving energy on the uphill, and letting go on the downhill, though not too much as I need to save those quads.

At the start, however, I will certainly keep in mind Alberto Salazar's advice from his Guide to Road Racing, "By the time the race begins, your adrenaline is running full-bore, then suddenly (finally!) all that flight-or-fight hormone finds release. Your body knows what it's supposed to do: run! chase! go! The trouble is that it won't be giving accurate feedback for the first few minutes. A pace that feels easy will be way too fast."

"Be especially careful if a race starts on a substantial upgrade or downgrade. Starting too fast on an upgrade will suck energy out of you faster than doing so on the level."

While I have never run tomorrow's course in this set-up, the second half is familiar from different races; its key incline just before 30K is Burrard Bridge, which I have crossed in quite a few races now. And when I picked up my race package on Thursday, Tim and I drove the final 2K of the new course, as they are uphill. I have made a mental note to reserve extra willpower for this final stretch.  

The main pacing and race mantra I plan to use tomorrow is, Relax and let it happen, a serious piece of no-nonsense advice from Dessie Suttle, a good friend from Australia. Few people I know are more passionate about running than he is. A runner for more than 40 years, he visited us last year to run the Whistler 50.

While he considered this 50-miler his first real ultra, he technically had already done one—Six Foot Track in 1996, Australia's most popular trail 'marathon', when it was still a 47K course instead of the 45K it is now. Dessie ran a swift 5:00:07. 

A great storyteller with a photographic memory for every detail he's every read or heard about running, he's been a true student of the sport for most of his life. What I admire most about him is that he's kept running and racing all these years, even though he's no longer covering the 1500m in 4:23 (his 1975 PB), 3K in 9:23 (also 1975), 5K in 16:11 (twice, in 1985 and 1990) or the 10K in 33:06 (1985).

He also ran a 2:59:03 marathon in 1983.

During his visit, Dessie brought with him a well-thumbed paperback copy of the late Dr George Sheehan's This Running Life from 1980, and left it behind for me to read. I love Sheehan's Running & Being. I began reading it this week, and found another piece of advice I will keep in mind tomorrow.

"When I get on the line, I realize that the issue is 90 percent settled. My recent training, whether I am over or under or at my peak, the state of my health cannot be helped. These factors are out of my hands. They are behind me. I need no longer worry about them. I have to remember only two things; one, not to do anything stupid and two, not to quit," Sheehan wrote in the chapter called The Race.

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