After recovering her strength, Twilight insisted on returning to the workshop with you. Said recovery involved eating enough food to last you a whole day, mostly sugary. Some ‘snacktime’. Is magic bound to some sort of metabolic exertion? Might be worth investigating, but that’s one kind of mechanics you don’t really have the tools to measure. Either way, she is now fully reinvigorated. You suspect some sort of sugar-high; while you could normally outpace most ponies’ polite speeds with a power walk, Twilight was staying alongside you engaged in the bounciest trot you’d seen to date.