It was mid-morning before the six ponies plus one dragon awoke from their slumber. Rarity,Fluttershy,and Applejack soon departed to take care of their own affairs, while Spike returned to the library to do some chores assigned to him by Twilight. Rainbow Dash was the last to wake up, which gave Twilight some time to study her body and look for any early effects of the experiment. Sure enough there was. At first glance Rainbow looked the same, but closer inspection revealed that her body was now covered in a small,gentle layer of fat. It was hardly noticeable, but Dash's figure definitely had a subtle softness that it lacked just the night before. Nopony would be able to tell that the Pegasus had gained weight without taking a very hard look though.

Rainbow Dash awoke with a yawn and took a moment to stretch, "That was a heck of a party, Pinkie."

"Thanks Dashie, although I might have to make more snacks next time. You almost chomped through all of the ones I made for last night," Pinkie replied. She had been fully alert ever since she exited her sleep.

Dash rubbed the back of her neck awkwardly, "Heh heh, yeah, sorry about that. I just felt starving for some reason. Speaking of that, I should probably do a bit of working out to day to make up for all those sweets."

Twilight nodded an agreement, "That's a great idea Rainbow. I'm sure we could all use some exercise. But how about we have breakfast first?"

"Eh, I guess a light meal wouldn't hurt to start things off...,"Came Dash's reply.

Pinkie Pie began jumping up and down at the idea,"Oooh,oooh, breakfast, of course! I'll get right on it. We can have Pancakes, and french toast, and WAFFLES too!"With that Pinkie disappeared into the kitchen, undoubtedly about to make a buffet of a breakfast. It wasn't long before she returned with giant plates filled with stacks of pancakes,french toast,waffles,and other assorted breakfast items.

Twilight stood up to excuse herself for a moment,"I need to go use the restroom, you two go ahead and start without me,"with that she turned around the corner and made sure she was out of sight before charging up her magic. It was likely that the spells she used on Rainbow last night had worn off, so she recasted them in order to prepare the rainbow pony for another round of overeating. After waiting a few moments Twilight returned to the table where her friends were sitting to find that Dash had already gone through at-least four waffles and four pancakes each, and was eagerly chowing down on a slice of french toast. By the time she had finished stuffing herself she had eaten twice as much as both Twilight and Pinkie combined.

Pinkie Pie seemed quite surprised, as it was rare for one of her friends to be able to eat more than her at any given meal, "That was pretty big for a light breakfast,Dashie."

Dash let out a half chuckle, half groan, "Yeah, I think I might of went a little overboard, I'll just have to up my exercise a little is all"

"You seem pretty full. Maybe you should wait awhile."

Dash ignored Pinkie's advice and got up out of her chair, "Nah, it's better if I get a quick start," with that she headed for the door, walking slightly awkwardly due to her overfilled belly.

Twilight paused for a moment in thought. It was unlikely Dash would be able to exercise very effectively after stuffing herself like that. On the other hoof, Rainbow was a determined pony and would likely be able to counter the experiment if left to her own devices. It wasn't hard for Twilight to form a plan to counter this however. "Pinkie, why don't you go and make some snacks? Just in case Rainbow Dash gets hungry in the middle of her big workout."

"That's a good idea Twilight. I know some perfect snacks to give an athletic pony lotsa energy."

As Pinkie bolted back off into the kitchen Twilight casted the spell to "empty" Rainbow Dash's stomach, ensuring that she would get hungry quite early on in her workout...

Twilight helped Pinkie bring out another plate of snacks just as Dash was coming in for the third break she had taken in just a few hours. There was barely enough time to set the platter down before Rainbow started consuming the tasty treats as if there was an incoming food shortage. It was hard to blame her though. The more Twilight practiced her hunger increasing the spell the more power she was able to pack in to it.

Pinkie had certainly noticed how ravenous her friend had become,"You're sure going through these snacks quickly,Rainbow."

Dash, seeming not fully aware of how much she had really eaten, brushed it off, "It's no big deal. I'm sure all the running and flying I've done out there has been more than enough to work it all off."

With that Dash got up from the table and headed for the door once again,while Pinkie began taking the emptied tray back into the kitchen. Twilight took a quick moment to empty Dash's stomach with her magic before following Pinkie Pie. Since the day started she had been helping Pinkie Pie with making snacks. She had told her it was part of an experiment to make food tastier, and that Dash was simply the taste-tester. What Pinkie didn't know however was that Twilight was adding secret ingredients that upped the amount of calories in the snacks by a very large amount.

It was a few hours and a few more high calorie snack breaks later before Dash decided to call it in for the day,"Thanks for making all these snacks and keeping me motivated, but I think I'm going to head home and relax now."

"See ya around Dashie,"said Pinkie as Rainbow Dash exited Sugarcube Corner and flew away.

With that Twilight decided she might as well head home as well and jot down some quick notes on her experiment so far,"I think I'm going to go back home too, Pinkie. Unless you need me to stay and help you clean up."

"Nah, I got it Twilight. Have fun with whatever you're off to do!"

Twilight left Sugarcube Corner shortly after and let her mind wonder to thoughts about the first full day of her experiment. She had to admit that it had went better than expected. While Rainbow Dash did get quite a lot of exercise, she had also unknowingly consumed an amount of fatty food so large that it would take multiple days of full workouts to burn off. If things continued at their current pace Rainbow would soon be showing some noticeable physical changes to record.

Author's Note

I realize the story's been a little slow to this point, but I needed to get the build-up out of the way. Things should stay pretty interesting from next chapter onward.