Sustainability without compromises: evaluating the long-term quality of recycled versus virgin polyester sportswear
Creators: name: Claußen, Lars
Publisher: name: Loughborough University
Year: 2025

description: As a large contributor to environmental pollution, the sports apparel industry is transforming towards greater sustainability and circularity (Niinimäki et al., 2020). Extending the lifespan of garments and switching to more sustainable/recycled fibres are among the most effective ways of reducing the industry’s environmental impact (ECOS, 2021; United Nations Climate Change, 2021; Wiedemann et al., 2021; WRAP, 2017) . These suggestions are also increasingly adopted in policies (Directorate General for Environment, 2022). However, the market share of recycled fibres is stagnating, and the utilisation/life span of garments has decreased in recent years (MacArthur, 2017; Textile Exchange, 2023). It is suggested that both are related to quality(Aakko &amp; Niinimäki, 2022; Botwinick &amp; Lu, 2022; Cassidy, 2017; Gabrielli et al., 2013; Joy et al., 2012; K. M. Laitala et al., 2015; López et al., 2014; Majumdar et al., 2020; Niinimäki et al., 2020; Wagner &amp; Heinzel, 2020). Therefore, the focus of this thesis was to investigate the long-term material and perceived quality of recycled and virgin polyester sportswear. In Chapter 2, Expert interviews and a consumer survey were conducted to conceptualise sports clothing quality from the perspective of industry professionals and consumers. Chapter 3 examines the evolution of material and perceived quality of sports T-shirts made from virgin polyester, mechanically recycled polyester, and mechanically recycled polyester containing ocean plastic over 18 months of real-life wear. Chapter 4 examines in-store perceived quality and material quality of the same T-shirts after repeated washing, comparing the findings with those from real-life wear (Chapter 3). Chapter 5 explores the perception of touching the T-shirts, while Chapter 6 investigates the perception and physiological responses during exercise while wearing the sports T-shirts. Key outcomes are: 1) A holistic sports clothing quality framework that provides a terminological basis for communicating and measuring sports clothing quality. 2) Recycled and virgin polyester T-shirts demonstrated consistent perceived quality over extended wear and repeated washing. 3) Despite significant but small differences in certain fabric parameters between wash-ageing and wear-ageing, a repeated wash cycle test is proposed as a practical and effective method to simulate material quality changes that occur during real-life wear. 4) In situations where clothing is mainly perceived by touch and trying on, perceptions of clothing quality and comfort differed between recycled and virgin polyester sports T-shirts. The recycled polyester T-shirts were perceived to be of higher quality than the virgin polyester T-shirts. No differences were found between sports T-shirts made from recycled and virgin polyester during real-life wear and exercise perception. Overall, this thesis has provided a detailed insight into the long-term quality of recycled and virgin polyester sportswear and how best to test for longevity in garments. Findings are relevant for the development and marketing of sports clothing.