Back in the mid to late 1970s, there was a morning TV show where the Caucasian male North American host did calisthenics on a mat outside on some green grass with (I think) a somewhat large body of water in the background. They played some kind of morning jazz music incorporating xylophone I believe. The host wore a sky blue & white short sleeved body suit, pants - not shorts. I seem to recall he was the sole person in the show. What was the name of this show?
Not sure if he's your guy, but Jack Lalanne had a morning exercise show from the 1950s to 1985. He was noted for having a minimal set and using household items rather than dedicated exercise equipment. Here is a video. You can see that he is inside rather than outside, but he is in front of a window with a lake or pond outside behind him.
He appeared for years on American morning news shows promoting fitness and healthy lifestyles. He lived to be 96 (died in 2011) and was still promoting fitness in his final year.