I was thinking about the commands you use, whether voluntarily or involuntarily, when telling your horse to go faster.
For example, I... when I want my mare to gallop full out... I will shorten my reins about a foot and a half [without realizing it] (I ride with very loose reins), start urging her on by using the hand the reins are in and 'throwing' that hand up by her ears and back repeatedly, and adopt a very grizzly tone of voice and scream "Hike, Hike!"...
My girl knows that 'hike' means 'run' and anytime I say it she gets antsy and energetic and wants to go.
What about you guys? What do yall use/do to get your horses to gallop?