25K Trail Race Disaster: Effect of Seasonal Allergies on Running Performance

This Sunday I ran the Pineland Maine Trail Festival 25K on a beautiful course through woods and fields on wide smooth trails magnificently laid out for nordic ski racing, hilly ups and downs!
Last year I ran at a solid 8:46 pace on a damp and humid day after rain overnight. Last Sunday I ran 24 minutes slower on a hot, dry day. I started at the same pace as last year, had equivalent training but after a bit more than an hour started slowing down dramatically.

Still doing OK here...

While I had plenty of energy my legs just stopped wanting to move.

Miles of Freshly Cut Field...and Pollen

So I got to thinking about Boston 2014 ... the exact same weather conditions as this Sunday's race whereas 2015 was raining and cold. In 2014, I ran more than 30 minutes slower at Boston than 2015 with the exact same no legs feeling as at Pineland this year.

The couple of days before each of the disaster races I had congested nose, upper airway and ears. I slept poorly and I usually sleep very well even the night before races, so not race nerves. I have noticed the last few years I am getting more allergy symptoms.Was my performance due to age, or as has been predicted after the long harsh winter by increased pollen in spring, a phenomenon scientists are predicting will be on the rise with global warming?

I definitely conclude pollen or other seasonal allergies affected my race performances. The conditions, including weather and pollen count for both "successful" and disastrous races on the same course with similar training lead me to this conclusion. I took no medication before either race.

So I went to Google and found the following fascinating thread on Let's Run. Many of the posters are elite runners ( sub 29 minute 10K, sub 14 minute 5K) who have seasonal allergies and concluded that the only explanation for catastrophic performance in spring are allergies. Some of the stories are striking in their similarities to each other and to what I expereince. In fact Galen Rupp was just a week ago pulled from a major race as the pollen was high. Many solutions presented and everyone's allergy profile is different but basically for a month or so in spring, in areas where there is a lot of vegetation, many of us have to set reasonable race expectations if the forecast is for high pollen counts and low dew points.  Both of my disaster races were on very high pollen count warm dry days. Both of my decent races on damp, wet days.

What am I going to do? I am trying Flonase a steroid OTC nose spray that helps prevent release of inflammatory substances to the body as well as an OTC antihistamine Zyrtec. Others on the post suggest "pine bark extract. In addition to medications there are several things one can do to prevent pollen from being easily absorbed see this article: time of day for your run, cleaning and changing right away, wearing a hat, etc... I will try all of these but mainly I will re set expectations for performance when the pollen conditions are bad as it seems that while many of these remedies reduce symptoms they don't get at the root problems of the allergy that can cause a decrease in performance.

Have you noticed similar effects of seasonal allergies on your race and training performances? What has worked for you?