I haven't noticed too much about how much strength I have over the seasons, but I did notice something interesting while waiting for my car to get fixed.
In hot weather, a car's battery works very hard to keep the car running, but the heat drains a lot of power from the battery.
In contrast, cold weather works to keep the battery, the power source, at a cooler temperature, so less demands are placed on it.
In short, if you live in a hot climate, your car battery's life is greatly diminished. I guess the same can be said about our bodies.
Personally, though, I feel more tired during these past few months. Yet, I haven't been really keeping tally in regards to the seasons, as I stated.