Abstract: Articles comprising fibres that change colour when they are stretched, thereby giving an indication of the tension being applied to the article. The present invention can be used with a variety of articles which require tension to be applied to achieve maximum functionality. These articles can include garments, such as compression garments, shirts, shorts, pants, socks, underwear, or hats; bandages, such as compression bandages; shoelaces; shoes; securities, sutures, ropes or cables.