USA Gymnastics made several transfers of millions of dollars into a closely linked foundation in the years before legal challenges related to sexual assaults by former national team doctor Larry Nassar triggered a bankruptcy filing by the gymnastics federation, tax documents show.

The payments came as a costly sexual-abuse crisis was emerging throughout the Olympic movement, and dwarfed the $100,000 per year that USA Gymnastics had routinely given the National Gymnastics Foundation.

The...