During my long run today (9 miles) my heart rate felt very elevated and the pace was easy. I've been averaging 35-45 miles per week and am working on my 1600m (mile) which i want to bring down for track season. It seems like during climate changes i get short of breathe for some reason and i can't figure out why. I live in Florida and the temperature has been fluctuating a lot lately, and when it goes from warmer temperatures to colder ones my heart rate goes up and i sometimes get short of breath. I eat pretty healthy for the most part I don't think I'm over training because I've been doing the same workout each week for a couple months now. Does anyone have any ideas why this is happening?
Some extra information:
Monday:Tempo Run 6 miles 6-6:15 pace
Tuesday: Cross training normally an insanity video workout, biking, or swimming
Wednesday: Recovery 3-6 miles
Thursday:Fartlek with 3-4, 3 minute surges of 5:30-5:45 pace
Friday: Rest or easy 3-6 miles
Saturday:90 minute Run
Sunday: Rest
1600m pr:4:22
800m:1:51.52
Thanks for the help in advance.