Ku dhammaystir weedha soo socota: Ciyaaraha Olombikada Xagaaga 2008 ee Beijing, Jansen waxay balaarisay barnaamijkeeda dabaasha laba dhacdo: 200-mitir oo qaab xor ah iyo 4 × 200-mitir oo qaab xor ah. Waxay tirtirtay FINA B-caadiga ah ee soo gelitaanka waqtiga 2:02.20 (200 m qaab xor ah) laga bilaabo Danish Open ee Copenhagen. 200 m oo qaab xor ah, Jansen wuxuu ku tartamay kaalinta afaraad iyo 34aad ee guud ahaan isla heerkulka Athens isla markaana wuxuu si sax ah hal ilbiriqsi uga horreeyey Lynette Lim oo reer Singapore ah 2:01.30. Waxay sidoo kale la shaqeysay Hjorth-Hansen, Micha Østergaard, iyo Lotte Friis
4 × 200 m oo qaab xor ah. Dabaasha saddexaad, Jansen wuxuu diiwaan geliyey kala qaybsanaanta 2:00.31, kooxda deenishkuna waxay ku dhameysteen heerkulka hordhaca ah ee tobnaad guud ahaan iyadoo leh rikoodh deenish ah 8:00.81.