Is it easier to work out in Fall vs. Spring?

Factual Questions
1

Over the past few years I have noticed that it tends to be more difficult to maintain a high cardiovascular workload during Spring and Summer, than in Fall or Winter. This isn’t an extreme shift, I simply find myself “winded” less often even though I am trying to push toward the same workout load.

Anybody have any ideas? Is it the seasons? Do you think I might have allergies (I have none that I know)? Could it be the temperature?

Any comments are appreciated.

Thanks!

2

There are a fair number of websites talking about exercise and temperature/humidity. There are a few answers on this one, though it’s not really to do with seasons per say. It also depends where you are I think… summer and fall condidtions could be quite different in Florida VS Alaska for instance.
(ps beware of the annoying pop up windows when you close that page I linked to)