James Gunnar Nixon (born January 13, 1993) is an American track and field athlete who competes in the decathlon.

[1] He attended Edmond Santa Fe High School, where he started taking part in decathlon competitions and broke the national high school record with a score of 8035 points (which brought him the Gatorade Track and Field Athlete of the Year Award in the men's section).

[2] He won at the Arcadia Invitational high school competition with a meet record of 7573 points (with junior implements).

In his first season for the Arkansas Razorbacks he broke the world junior record for the indoor heptathlon with a score of 6022 points.

Joined Coach Jeremy Fischer[9] and Craig Poole[10] at USA Olympic Training Center[11] in Chula Vista, CA.