JEFFERSON CITY – Starting with his junior year at Richmond, Jacoby Johnson chased the boys 400-meter dash record. On May 27 at Adkins Stadium, during his final high school track and field meet, Johnson overtook the record. Then, on May 28, he outdid himself. Johnson, who graduated May 15, set the record during the 400 preliminaries at Class 3 state competition, winning his heat and finishing second overall in 49.42 seconds. His time broke the 32-year-old school record, 49.6, set by Bobby Johnson. “I’m not going to lie to you, I really wasn’t thinking about the school record, because I was just trying to get in the zone and run my best race … all year,” he said. To get in that zone, Johnson kept to himself and collected his thoughts, he said. He also went through a routine of listening to music and occasionally stretching. His musical playlist consisted primarily of rapper NBA YoungBoy, he said. “He kind of gets me in the zone,” Johnson said. Having set the school record,…