Ng is of Chinese and British descent.[2] She took up swimming at an early age.[3] She trained at the Mantas Swimming Club along with Hung Cee Kay.[4] In swimming at the 1986 Asian Games, she won bronze in the women's 4 × 100 m freestyle relay with Hung, Fu Mui, and Lee Sau-mei.[5] She studied chemical engineering at the University of Leeds. Following her return to Hong Kong in 1993, for her final appearance as a swimmer at the Asian Games in 1994, she won silver in the women's 4 × 100 m freestyle relay. After a break from sport, in 1995 she took up rowing.[3] She represented Hong Kong in that sport at the 1998 Asian Games,[6] and in 2000 became the first Hong Kong athlete to compete in two different sports at the Olympics.[3] The following year, she retired from competition.[7] She co-founded the Tritons Triathlon Club in 2008 with fellow Olympians Annemarie Munk and Michael Tse (謝家德). Fenella also served as President of the Hong Kong Triathlon Association which grew to 2,500 members.[8]
^"香港三項鐵人總會執行委員新任命副會長及秘書" [New Vice President and Secretary of Hong Kong Triathlon Association Executive Committee]. Hong Kong Triathlon Association. 18 September 2014. Retrieved 6 January 2018.
^ abcSallay, Alvin (14 September 2000). "Different strokes". South China Morning Post. Retrieved 6 January 2018.
^"1986年漢城 ( 亞洲運動會 )". Sports Federation and Olympic Committee of Hong Kong, China. Archived from the original on 6 October 2018. Retrieved 6 January 2018. "1986 Seoul ( Asian Games )". Sports Federation and Olympic Committee of Hong Kong, China. Archived from the original on 6 October 2018. Retrieved 6 January 2018.