[CrossCheck]

I heard them say on the telly that Armstrong's heart is one third larger than normal. The great horse Secretariat also had a heart that was quite a bit larger than normal. All other things being equal, this is probably part of the reason why Armstrong can overwhelm the competition in the mountains.

[Toidylop]

Just overheard from one of the OLN commentators (forgot which one?) saying Lance's resting heart rate is around 35 pulses per minute!!! Is it possible? Wow... No wonder he has the heart to win.

[Prodigal Son]

Usually a long distance athlete who has trained in his sport for years and years will have a larger heart. My wife was a cross country skier for most of her life- she was on the German National Team. Her heart is bigger than mine. Also, she hasn't trained for 8 years now and her heart rate is still in the low 50s. When I met her, it was much lower. It was freaky to lay my head on her chest and listen- the pause between heartbeats was much longer than normal. Also, superbly trained distance athletes like this, their heart pumps harder as well. The muscle squeezes harder. It takes a lot more exertion to raise their heart rates to what us mere mortals would have given similar exercise. When I run with my wife, my heart rate is way up there but her's doesn't seem to be that high at all.

[desertcry]

Probably equally important is his lung capacity is extraordinary.