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15. Michael Kimmel, Manhood in America (New York: Free Press, 1996), 120.

16. David Whitson, “Sport in the Social Construction of Masculinity,” in Sport, Men and the Gender Order, eds. Michael A. Messner and Donald F. Sabo (Champaign, IL: Humans Kinetics Books, 1990), 23.

17. Don Sabo, “Sports Injury, the Pain Principle, and the Promise of Reform,” Journal of Intercollegiate Sport 2, no. 1 (June 2009): 145–52.

18. Maya Dusenbery and Jaeah Lee, “Charts: The State of Women’s Athletics, 40 Years After Title IX,” Mother Jones online, last modified June 22, 2012, www.motherjones.com/politics/2012/06/charts-womens-athletics-title-nine-ncaa.

19. Joanna L. Grossman and Deborah L. Brake, “The Big 4–0: Title IX Puts a Fourth Decade Under Its Belt,” Verdict (blog), Justia, June 26, 2012, https://verdict.justia.com/2012/06/26/the-big-4–0.

20. Whitson, “Sport in the Social Construction,” 26.

21. Eric Anderson, “Orthodox and Inclusive Masculinity: Competing Masculinities Among Heterosexual Men in a Feminized Terrain,” Sociological Perspectives 48, no. 3 (2005): 337–55.

22. Paul Langhorst, “Youth Sports Participation Statistics and Trends,” Engage Sports Blog, March 8, 2016, www.engagesports.com/blog/post/1488/youth-sports-participation-statistics-and-trends.

23. Jonathan Drennan, “Rugby’s Decline Continuing Apace in an Apathetic Australia,” Irish Times online, last modified December 8, 2016, www.irishtimes.com/sport/rugby/international/rugby-s-decline-continuing-apace-in-an-apathetic-australia-1.2898261.

24. Michael Atkinson and Michael Kehler, “Boys, Bullying, and Biopedagogies in Physical Education,” in THYMOS: Journal of Boyhood Studies 6, no. 1 (Spring 2012) (ed. Reichert and Nelson): 181.

25. US Centers for Disease Control and Prevention online, “A Fact Sheet for Youth Sports Parents: Heads Up Concussion,” last modified December 2015, https://docs.google.com/viewer?url=https%3A%2F%2Fwww.cdc.gov%2Fheadsup%2Fpdfs%2Fyouthsports%2Fparents_eng.pdf.

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27. Ben Rains, “Study Shows Concussions up 500 % in Youth Sports,” Sports Illustrated online, last modified July 13, 2016, www.si.com/tech-media/2016/07/13/concussions-youth-sports-rising-nfl.