Effects of athletic training on the equine heart:
Do horses with big hearts run faster?
Do horses with big hearts run faster?
Lesley E Young, Katherine Rogers and James LN Wood
Heart size matters
HBLB funded research showed that if a racehorse, especially a jumper, has a large heart, it has a significant advantage due to superior oxygen supply. Eclipse, Phar Lap and Secretariat all had large hearts.
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