It's never too late. Starting 3-4 days ago would be good. But seriously... dude, you've been signed up for this race for a while right.... well... i guess you could have signed up just last week.
Dewpoint of 75... could be worse. Last month i went for a run after work and the air temp was 86F...that's not so bad.... dewpoint was 80F. Worse, it was windy. I say worse, because going out you had zero airflow with the wind at your back.
Of course that's a normal morning 3-4 months out of the year in some parts of Texas.
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