Today I did my usual Wednesday 10 mile bike ride. This ride is a little more challenging, because there is a series of ups and downs (nothing super steep) but since I only have 3 gears
I have to do sprints to get enough momentum not to lose it all at the top of a grade. It gets pretty aerobic.
My BP about 15 mins afterwards was 116/76, and pulse was still a little elevated at 91. This seemed like a pretty normal "post exercise" reading.
I took my BP again almost 2 hours later, and it had dropped to 106/70, pulse 72!
Conclusion: morning exercise lowers my BP in the morning, sometimes as much as 20mm Hg below my "normal" morning reading. The effect seems to last for several hours.
I have taken my morning BP often enough over the years to know that I don't otherwise get readings below 115/whatever and certainly not below 110/whatever, so it must be the morning exercise.