On many of my runs recently, I've noticed that my heart rate is way higher than normal, especially for low- to middle-aerobic paces. I also feel like I can't get a full breath, and my nose runs / my sinuses are super achy when I'm not running.
Here in the Northeastern US, it seems like early fall is a prime season for allergies, and as someone super sensitive to ragweed, I feel like I'm getting walloped right now.
Can allergies lead to a higher-than-normal running (and even resting) heart rate, either directly or indirectly? For what it's worth, I've been doing a lot of my mileage on grass, so my exposure to potential allergens is probably quite acute right now.