rare? hell you know its the good looking people that are more likely to end up with herpes, aids..etc. Even body builders get cancer. go to a cancer survivor walk and you see all kinds of fit bodies.
Truth is you can have no clue just by looking at people if they are clinically healthy or not.
Eh, those kinds of health issues aren't something I consider with this. Obviously, opportunistic diseases don't care about physiological condition (for the most part).
actually your dead wrong there. i look very fit, i lift. 6pack n all but still have high blood pressure and your body type does not guarantee you can run any length of distance. And nothing i do is going to get rid of genetically transferred heart diseases...assuming it was passed to me.
You win that point sir.
However, body type, in terms of muscle-fiber type, definitely leads your body to be far better at one type of activity over another. In terms of running, you're really either destined to be a sprinter, or an endurance runner. Whether you are anywhere near the best at either type is another question, and whether your body can even train for both types is also another matter altogether. And generally, someone with a sprinter's muscle style will always be better at sprinting than distance running - and typically such a person will be better at that activity than someone who has the opposite majority muscle-fiber type. Like you said, it doesn't entirely dictate what you can do and how well you can do it, but it pushes your body in that direction. If you aren't competitive about it, it doesn't even matter. Any person can train to run a handful of miles or similar cardio activity, but training for competition you tend to listen to your body. I don't know if you can be a highly competitive sprinter if your body has fewer fast-twitch fibers and more slow-twitch fibers.
Of course, you can train your heart out to build up more fast-twitch if you care to, but it's working against the current in this case.
One more that proves your point: someone could look in perfect health now, but has a disease that will essentially force muscle atrophy sometime in the future, or some other systemic disease like RA or Lupus or whatnot. Sometimes, especially when young, those diseases won't stop you from reaching peak fitness - but they will cut that ride short at some point.
With another read through, I'm not entirely sure I actually understand your message though. So you are into physical activity, but don't really run much?
Of course a fatty who runs more than you will be able to run further and faster than you - you can't just put on running shoes and go and expect it to be a great run.
Also, in terms of true heart disease, that is different, because its more of a defect than a disease. Without surgery, it can be hard to fight against - and depending on the severity, it will seriously impact cardiovascular performance.
That's not something you can readily change, and it's also not something I'd consider part of "health". Like some other health issues, you inherit it, and while not all inheritable health issues are uncorrectable, heart disease is one that typically needs correction by an outside party.
That's more of a "bad luck" than unhealthy choices. When I speak of fitness and health, I'm focusing on self-correctable and self-manageable issues. Blood pressure can be corrected, cholesterol can be corrected... a whole novel worth of issues can be improved (not necessarily cured) through proper nutrition - proper nutrition requires exercise... but not for the point of burning more calories through energy expenditure, but through the chemical processes that happen simply to support the physical activity. It helps your body burn up what you didn't actually need, and helps make sure everything is getting utilized.
But obviously, if you have an uncorrectable kink in the cardiovascular system, improving your heart and blood health is nigh an impossible task, at least doing so entirely on your own. It can be hard to do the physical activity necessary to help your body combine the improved nutrition if your heart cannot sustain that level of effort.
There's a reason the medical community is so in love with diet and exercise for heart and blood health. It's not necessarily the most efficient diet, but the exercise isn't supposed to be an additional weight to lose weight - it's supposed to be a way to let your body enter into a more primal, natural mode - where it is far more efficient at utilizing what you give your body.
And wait, what are your "heart diseases". I notice you made that plural, but only mentioned high blood pressure.
What are you currently doing for your blood pressure? Consuming Omega 3s, at all? Focusing on monounsatured fats? (polyunsatured fats are also good, to an extent - you need those fatty acids, after all)
Such fats will do wonders, alongside any kind of cardio activity you can do, to help slowly bring your lipids into check.
And you should be trying to get a few grams of Omega 3s and other fatty acids, every day. You're body might not seriously complain when you don't get enough, but it will greatly appreciate getting more if you aren't getting enough - the body uses good lipids for everything, and Omega 3s are especially useful in the construction of new tissue in the CNS.