impulsion

n. thrust, push; impetus, movement caused by a push or thrust; impulse, sudden whim or desire

Impulsion is the pushing power (thrust) of a horse, which comes from his desire to move powerfully forward with energy. However, speed does not create impulsion, and a rushing horse is more likely to be "flat" than impulsive. A horse can only have impulsion if his hind legs are engaged and his elastic back allows the power to come through.
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Noun
1. a force that moves something along
(synonym) drift, impetus
(hypernym) force
(derivation) impel, force
2. the act of applying force suddenly; "the impulse knocked him over"
(synonym) impulse, impetus
(hypernym) drive, thrust, driving force
(derivation) propel, impel

n. impetus, pulse; impulse, drive

n. impulse; impulsion