conv: I took up running and I started seeing a huge improvement in my cardiovascular endurance. I felt so certain that I would hit my 5km goal in no time! I took up running and I started seeing a huge improvement in my cardiovascular endurance. Nice_comma_ Was it hard to start? Unimaginably hard. But once I got into it I couldn't stop. I'm feeling pretty certain that I'll hit my 5km goal in no time. Wish i could run close to 5km_comma_ i'd struggle with 100 meters. I used to be that guy too. If I can do it_comma_ you can do it.