The 34-year-old was spotted working out on Friday in West Hollywood while wearing figure-hugging black gym clothes.
West recently turned heads when she went platinum blonde – though the style choice was more bold than permanent.
“It was a really last minute decision, and I loved taking this risk,” she told PEOPLE in Paris.
West was photographed wearing her signature brunette shade on Thursday while taking daughter North West to dance class. She spent less than a month with the new ‘do.
“She just did blonde for a moment and wanted to be back dark before she goes to Armenia next week,” a source told PEOPLE of the change.