An 85 yr old man is having his annual physical and the doc is amazed at how fit and healthy his patient is. So he asks the man how his sex life is these days.
"Pretty good." says the octogenarian. "But I must admit I'm a little out of breath and sweat a lot during the second time."
Astounded, the doc asks the guy why he sweats during the second time.
"Well…", replies the patient, "It's always hotter in July than it is in January."