Yale University:

In 1909–10, football faced a crisis resulting from the failure of the previous reforms of 1905–06 to solve the problem of serious injuries. There was a mood of alarm and mistrust, and, while the crisis was developing, the presidents of Harvard, Yale, and Princeton developed a project to reform the sport and forestall possible radical changes forced by government upon the sport. President Arthur Hadley of Yale, A. Lawrence Lowell of Harvard, and Woodrow Wilson of Princeton worked to develop moderate changes to reduce injuries. Their attempts, however, were reduced by rebellion against the rules committee and formation of the Intercollegiate Athletic Association. The big three had tried to operate independently of the majority, but changes did reduce injuries.

Please answer a question about this article. If the question is unanswerable, say "unanswerable". Who attempted to enact measures of soccer reform?
unanswerable