In an ever changing market, heavily influenced by social media, the altheisure segment continues to grow exponentially. Activewear is no longer just for working out, it has become a versatile category of clothing that can be worn for various activities both day and night. Due to its wide acceptance, athleisure is not only a personal style choice, but a lifestyle trend inspired by social media. In today’s society, brands rely on their social media platforms, specifically Instagram, for a large amount of their exposure. This increased exposure allows for potential growth within the sustainability sector of the athleisure market. Sustainable activewear companies such as Patagonia, Outdoor Voices, and Groceries Apparel use their Instagram accounts to promote products and increase consumer engagement. This study intends to use qualitative research methods to gather data that shows the correlation between a brand’s Instagram content and millennial women’s perceptions of athleisure. This study will explore influential advertising techniques used on Instagram by these sustainable activewear brands. The research method will include observing and tracking comments and hashtags from the consumers, as well as reposts, influencers, and events promoted by the companies. This study is expecting to show results of a positive relationship between the brands’ social media platform, Instagram, and the consumer following. In the qualitative data research stated above, observations will show from the content analysis that brand involvement with consumers through Instagram influences both purchase decisions and lifestyle choices of millennial women. Overall, this study expects to further investigate the impact that increased exposure of sustainable altheisure companies will have on female consumers. The impact of the increased exposure will be based on the various advertising techniques used by each brand on Instagram. A positive correlation will be observed and determined by the end of this study.