Kammala wannan jumla: Adlington ya wakilci Birtaniya a gasar Olympics ta 2008, yana fafatawa a cikin mita 400 da mita 800. An kuma shirya ta yi iyo a cikin
4 × 200-mita freestyle relay amma ya huta a cikin zafi kuma tawagar ta kasa cancanta zuwa wasan karshe. A cikin zafin mita 400 na 'yanci, ta karya rikodin Commonwealth tare da lokacin 4:02.24. A ranar 11 ga Agusta 2008, ta lashe lambar zinare ta Olympics a cikin wannan taron, tare da lokacin 4:03.22, ta wuce Katie Hoff na Amurka a cikin mita 20 na ƙarshe. Ita ce mace ta farko da ta lashe zinare a wasan iyo a Burtaniya tun bayan Anita Lonsbrough a shekarar 1960. Ita ce 'yar wasan Ingila ta farko da ta lashe lambar zinare fiye da ɗaya a Wasannin Olympic guda ɗaya tun lokacin da Henry Taylor ya lashe uku a 1908.