Training & Nutrition - Cardiovascular stystem gets better with lower bodyfat %age?

Let's say that there are 2 identical people with the same fitness level. They both weigh 150 pounds, but 1 is at 9% bodyfat and the other is at 14% bodyfat. They are identical in every way except for the fat factor I just mentioned. Whose heart is working harder?

I'm thinking the person at 9% bodyfat because the extra muscle he's carrying needs that extra blood.

What do you think?

You need to clarify. What do you mean by same fitness level? Are there heart bpm the same? VO2 Max the same? Ability to hold 80% VO2 Max the same? Capillary "coverage" in their muscles the same? It's such a tough question to answer.

Last summer, I lost 8 pounds for various reasons, not exactly connected to riding. I rode about my normal summer amount. After losing that weight, I was much faster than I have been before at that time of the year, including on the flat. I set some PRs on my little riding courses around home. I gained that weight back and now am training well and having some good rides, but I'm not as fast as I was then. I'm trying to lose it again, but it's slow.

Nutty question. Throw this one away and try one that makes sense.

The affect of body fat on cardiovascular health only expresses itself at the very extreme ends of the spectrum. For instance, why not discuss, 7% and 35% body fat.

At those levels, one could safely say the CV system is compromised by fat.