Monday, June 15, 2009

Positive Splits

A Positive Split is defined as running at a slower pace for the second half of a race. Most of us have done it. Planning on it, however, is not the best idea. It could actually be race suicide.

At the beginning of a race, we feel great. We've fueled, we've hydrated, we've rested. For a marathon, we've had a nice, long taper and our legs are raring to go. Mentally, it is very hard to hold back. You are thinking to yourself, "I might as well run strong now...I'll slow down later, no matter what."

Remember this: Setting out to do positive splits is a self fulfilling prophecy. If you go out fast, hoping to take advantage of your early strength, odds are you WILL slow down in the later miles. That is best case. There is also the chance you will run out of steam altogether. Going out too fast taxes the muscles early and uses up your muscle glycogen early. This causes negative feelings. Seasoned runners can run this way, because they know how to deal with feeling lousy toward the end of the race. Sometimes elite runners will go out fast, hoping to force competitors to go out faster than they should.

I was guilty of this strategy two weeks ago. I went out fast early, taking advantage of the downhill in the early miles along with my great mood. Mentally, I kept "banking" my time, knowing that I had several minutes to spare for my goal. As my glycogen depleted and my energy waned, I saw that bank of time dwindle away. Early on, Laura and I even talked about how fast we were going and mentioned that we knew people that had done it successfully. Just because others can do it, doesn't mean that I am meant to. I need to learn to have confidence in my race plan and stick to it. Once I can figure out how to do it, I can better coach people to do the same.

The best way to run a race is running an even effort (constant pace). Figure out what your average pace for the race will be, and start out at that pace. If there are hills, you should take those into account.
"A good rule of thumb for uphill of 100 ft/mile gain is to add 20 to 30 seconds/mile to your average pace while on steep uphill of 200 ft/mile add 40 to 70 seconds/mile. For downhill, subtract 15 to 20 seconds/mile for 100 ft/mi and 20 to 40 seconds for 200 ft/mile."*
Personally, I have a hard time doing math in my head during a hard run. That is why a pace bracelets or temporary tattoos are often helpful, especially in a marathon. I think if I would have started out at 9:05 pace like I had originally planned, I might have met my goal of finishing under four hours. I'll never know. I am pretty sure that if I would have started out at 9:30-9:40, I would have had around the same finish time (4:16), but felt much better at the end. The best thing about last month's marathon is how much I learned from it.

Often the best results come from negative splits. This is a tough one to plan for. No one really wants to start out slower than your goal pace. That is why negative splits are often achieved when someone reaches a stretch goal. Some people are able to do this quite nicely, however. Negative splits are very powerful psychologically. You feel strong and pass people in those last miles. It may even lead to even faster splits. That is what happened to me during the Carlsbad Half Marathon when I achieved my PR. That race is still my favorite race ever. I felt a euphoria at the finish line unlike any other race. I ran negative splits during that race, having my fastest mile the last mile of the race. This happened because I started out conservatively in the beginning.

The lesson from all this is to plan your race. If you just go out and run it, you'll likely start out too quickly. Proper training and preparation will give you everything you need to run a great race for you. I will remind myself of these things as I prepare for AFC in August. Last year I ran out of gas. This year I want to finish strong.

Happy running.

* "Marathoning- Start to Finsh" by Patti and Warren Finke.


AKA Alice said...

Yeah...running even or negative splits in AFC is a real challenge (those first five steep downhill miles...), but I tried it last year...and it almost worked...(day-um heat!)

Can't wait to find out what you learn about heat training...of course if today's weather holds, it won't be an issue.

What is up with the weather here?

Irish Cream said...

Lots of great info! Thanks so much for sharing!

I am DEFINITELY going to keep this in mind come the 27th! As difficult as it is to keep the pace down early on, I have no doubt that it leads to a far better result in the long run!

Also, thanks so much for the RRCA link . . . I think I'm definitely going to have to check the program out. I am just LOVING reading about everything you've learned!

Irene said...

100% agree with everything you've said! It's so easy to get caught up in the moment and burn out too soon. Planning and sticking to the plan is everything. That being said, knowing what works for you is everything, too. :)

tgorourke said...

It sounds like you really did learn a ton at your course a few weeks ago. Thank you very much for the email you sent me and also for this post. I am going to be going home to my mom this weekend, to look at the Boilermaker course (which is pretty much all hills, as you saw) and get my mental plan together for the race.

Oh, and just so you and AKA Alice know, we are having weird weather here too - our highs are in the low 70s, and we're getting rain almost every friggin day. Very weird!

Marathonman101108 said...

That's what I like about the Jeff Galloway training program that I'm doing. It does exactly what you mention, plus allows this 52 year old man to take walk breaks every mile, or as needed. Great post, Lisa.

Oz Runner said...

hey, got the orange gu yesterday, thanks a bunch!

Alissa said...

Great post. You have so much running knowledge! Your blog is so informative! Positive splits usually work for me when I'm running a race for "fun" and I start out easy, not trying to break any records. Then I get to the half way point, feel so good that I just decide to push and see what happens. Can't say I've had this happen in marathons though. Halfs and less it does seem to work though.

RunnerMom said...

I know, but it's so HARD. I've had even splits, but I've never been able to accomplish negative splits. Luckily, I have many races in the fall to practice in!

Getting exciting about training in two weeks! I got the email about getting CPR/First Aid certified, but cannot get it in until July 24. I hope to take the test before then so when I send in my First Aid/CPR stuff, I'll be official. Unfortunately, my coaching group starts on the 20th. I figure that's close enough!


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