Another "Engineer"s Idea of Fitness :-)

[Physfitfreak]

Lot's of them. Only requires that you be an "engineer". Here is one more:

https://streamable.com/a8ot4w

[Physfitfreak]

Another product of cro-magnon "engineer" type early human, aiming at
perfecting fitness:

https://streamable.com/g9orpy


Go for it rbrown, go for your balls now. Do it for your dick to turn
brown before yours in entirety are turned brown.