Swollen Ankels

I've gone to two different physicians at one of the worlds best hospital systems and neither one have been able to tell me why do my ankles swell when I get hot (only in the summer this happens).  I been given blood tests and stress tests and all come back just fine.  I am 49 and considered in excellent shape & health.  Can anyone out there tell me why or better yet how to stop my ankels from swelling in the summer (it can be 100 degrees outside and as long as I stay in the A/C I'm fine.  Anyone????

[Cleveland Clinic]

I am not sure of the mechanism, except to say it may actually be related to your increased fluid consumption during these hot weather months. This may cause fluid accumulation in your ankles, either secondary to increased fluid or salt consumption.