Question: In what race was a Clay County, Kansas native world leader in 1970?

Context paragraphs:
Midwest National Air Center: Midwest National Air Center (ICAO: KGPH, FAA LID: GPH) is a public-use airport in Clay County, Missouri, United States.  The airport is located one nautical mile (1.85 km) north of the central business district of Mosby, near Excelsior Springs.  It is owned by the Clay County Commission and was formerly known as Clay County Regional Airport.

WWXL: WWXL (1450 AM) is a radio station licensed to Manchester, Kentucky, broadcasting with a full-time signal of 1,000 watts.  The station broadcasts a sports talk format.  The station also broadcasts the full slate of Clay County High School football and basketball games, select coverage of Clay County High School girls' basketball games, and select games of Clay County Elementary School football andbasketball games.  The General Manager of WWXL AM is Tyler Wolfe whose on-air name is The Wolfeman.

Clay County School District (North Carolina): Clay County Schools (CCS) is the School District in North Carolina that manages the County's public school system.  It is the only school system in Clay County, with about 1,200 students attending a total of 3 separate schools located on a central campus in Hayesville, North Carolina.  The system covers all of Clay County.

John Olness House: The John Olness House is a house in Kragnes Township, Clay County, Minnesota, just north of Moorhead on U.S. Route 75.  The house is listed on the National Register of Historic Places as an example of a link between the farm communities and the farm-related businesses in Clay County.  The architecture shows influences of the Queen Anne style, which stands out in Clay County because most buildings were in the local vernacular style.  The owner, John Olness, was a successful farmer, and he also owned several businesses in the nearby community of Kragnes, including the local grain elevator and lumber yard.

Ken Swenson: Kenneth Lloyd "Ken" Swenson (born April 18, 1948 in Clay Center, Kansas) is a retired middle-distance runner from the United States.  Swenson was the world leader at 800 meters in 1970 and competed in the 1972 Summer Olympics in Munich.

Clay County Historical Museum: The Clay County Historical Society Museum is located in Green Cove Springs, Clay County, Florida.  It is located in a former trail depot.  Exhibits include railroad memorabilia, a country kitchen display and a country store display.  It is operated by the Clay County Historical Society.  The museum is located at 915 Walnut Street in the Historical Triangle which also includes the 1896 county jail and 1890 courthouse at Walnut Street and Ferris Street (Hwy 16).

Clay Center, Kansas: Clay Center is a city in and the county seat of Clay County, Kansas, United States.  As of the 2010 census, the city population was 4,334.

Anybody Killa discography: Anybody Killa has released 6 studio albums.  5 on Psychopathic Records.  1 on Slangtown Records.  And a rerelease on his own label Native World Inc.  He has also released 1 EP and 1 greatest hits album on Psychopathic Records.  He has released 7 other EP's on his own record label "Native World Inc.".

Clay County Courthouse (Illinois): The Clay County Courthouse, located at 300 Broadway Street in Louisville, is the county courthouse serving Clay County, Illinois.  Built in 1913, the courthouse was Clay County's fourth courthouse; it has served continuously as the seat of Clay County government since its opening.  Architect Joseph W. Royer, who planned several other Illinois courthouses, designed the Classical Revival building.  The courthouse was added to the National Register of Historic Places in 2015.

Claycomo, Missouri: Claycomo is a village in Clay County, Missouri, United States.  The village’s name is a portmanteau of "Clay, Co" (Clay County), and "Mo" (Missouri).  The population was 1,430 at the 2010 census.  Ford Motor Company has an assembly plant in Claycomo.  Kansas City Assembly is responsible for building the Ford F-150 pickup trucks and the Ford Transit vans.

Supporting paragraphs: Ken Swenson Clay Center, Kansas
Answer: 800 meters