All of the cervus elphus group (elk and red deer) are at their absolute biggest at 8-11 years old. Weather, feed, genetics and predation will influence what kind of head gear they have on at this time. A lean year for moisture, or a year where they spent the entire season getting harassed by wolves, lions, bears or in Russia tigers will influence how much nutrition they get to keep.
We had cattle when I was a kid in a mountain pasture where they were harassed by a grizzly and he killed two cows near Dubois, Wyoming. They were the skinniest cows I had ever seen coming off summer pasture.