Credited with bringing the sport of ski jumping to Canada, he made his debut on the nearby Big Hill in 1915.

Despite holding the world record at the time, he was not allowed to participate in the 1928 Winter Olympics because the officials did not find it suitable for him to have to work his way to Switzerland.

Nelsen worked for the Canadian Pacific Railway, and moved to North Vancouver, British Columbia, where he raised a family.

He was born Nils Johan Nilsen to a Norwegian family in Seljeskogen in Salangen Municipality on 3 June 1894, as the oldest of six children.

Except for a brief period as a ski instructor, he worked as a brakeman and conductor for the Canadian Pacific Railway, whose flexibility made it easier to participate in tournaments.

Among his methods to improve his jumps was placing pieces of lead at the front or back of the skies to give optimal balance.

In British Columbia, he attended competitions in Nelson, Trail, Rossland, Princeton, Kamloops, Sandon, Nakusp, Kimberley and Cranbrook.

In Alberta, he attended tournaments in Calgary, Edmonton, Banff and Camrose; in eastern Canada in Ottawa and Montreal.

In the United States, he attended events in Mount Rainier and Leavenworth in Washington; Dillon, Steamboat Springs and Denver in Colorado; Salt Lake City; and Brattleboro, Vermont.

This was because it was regarded that simply building a larger hill would undoubtedly give a longer jump, and in part because such records did not take style into consideration.

These plans were stopped by officials from the British delegation, who felt it was inappropriate and not fitting for the team, and Nelsen never competed in any Winter Olympics.