A former gymnastics coach in Louisiana who admitted molesting more than a dozen boys — including some he promised would improve at the sport if they relented — has been sentenced to 65 years in prison, authorities said.

Jonathan M. West was sentenced Monday after pleading guilty to molesting 13 boys between the ages of 8 and 15 from 2015 through May, Jefferson Parish District Attorney Paul Connick announced Monday.

West, 27, who previously worked as a gymnastics and cheerleading coach at facilities in Metarie, Kenner and St. Charles Parish, molested the victims in some instances while driving them to gymnasiums. West also told some of the victims that the molestation would make them better at gymnastics, Connick said.

West was simply known as “Jonny” to six of his victims, according to victim impact statements read in court by nine people, including mothers of the victimized boys.

West was arrested in May after four boys spoke with police in Kenner, according to the New Orleans Advocate. Additional victims then came forward after seeing reports of the arrest, Connick said.

If he’s ever released from prison, a judge ordered West to be electronically monitored and to register as a sex offender for the rest of his life. In all, West pleaded guilty to 24 charges, including nine counts of indecent behavior with juveniles and eight counts of sexual battery. A judge ruled that his sentences will be served concurrently, Connick said.