Boat? was commercial air travel viable then?
Commerical air travel was in its infancy in the 1920s, and transatlantic flight of any kind was extremely unusual; the first west-to-east crossing by aeroplane was only made in April 1928, after the St Moritz Olympics, and aeroplane passenger services were not available until the late 1930s. The airship Graf Zeppelin made a one-off commercial crossing between Germany and the US in October 1928, regular crossings between Germany and South America only started in the 1930s. Our prospective Olympian would be looking at ocean liners to get to Europe, perhaps the appropriately-named Olympic of the White Star Line or rivals from the Cunard Line, United States Line, Hamburg America Line or similar companies offering transatlantic crossings.
A good portion of the team had slightly shorter journeys, though, already being in Europe; the driver of the gold medal winning five-man bobsleigh team, 16 year old Billy Fiske, was at school in France where he had discovered the sport. The brakeman, Richard Parke, lived in Paris and was also a racer. The team was filled by advertising in European editions of the New York Herald Tribune; Geoffrey Mason was studying in Freiburg, saw the advert, responded, was accepted sight unseen, and travelled to St Moritz ten days before the games started - the first time he saw a bobsleigh and met the rest of the team. After he collected his gold medal he returned to Freiburg by train, and never rode a bobsleigh again.