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After reading a book by Spitfire's personal trainer, Rainbow Dash decides that the best way to get closer to her ultimate goal of joining the Wonderbolts is to add strength training to her practices by having one of her friends ride her. However, when she decides that Twilight Sparkle is just the mare for the job, the pegasus gets a bit more than she bargained for.

Artwork by Piggybank12.  Used with permission.  Thanks to DPV111 for assisting me with story planning.