More than 750 of the USA's top Level 8, 9 and 10 male gymnasts will compete in the 2014 U.S. Men's Junior Olympic National Championships, May 8-11, at the Long Beach (Calif.) Arena. The event features competition in regional team, all-around and individual apparatus. Opening ceremonies were held last night.

Defending champion and current senior national team member Marvin Kimble of Milwaukee, Wis./Swiss Turners, is expected to compete.

For a complete list of competitors by session, click here.

The levels are determined by age and skill level. Level 8 consists of athletes who are 11 and 12 years-old; Level 9 athletes are 13 and 14 years-old. At Level 10, there are two age divisions, 15-16 year-olds and 17-18 year-olds. Each level has two divisions – Junior Elite and Junior Olympic.

For Level 10 athletes competing in the Junior Elite Division, the Junior Olympic National Championships are a qualifier to the P&G Gymnastics Championships (Aug. 21-24 in Pittsburgh, Pa.) where the Level 10 Junior National Team will be determined. Six Level 8 and ten Level 9 gymnasts from the Junior Elite Division will be named to the Level 8/9 Junior Olympic National Team at the conclusion of the Junior Olympic Nationals.

Competition begins today with three Level 10 sessions. Levels 8 and 9 get underway on May 9, also with three sessions of competition.

In the Junior Olympic division, the top 24 all-around qualifiers, plus the top 12 individual event qualifiers in each age group, advance to Saturday's Level 10 and Sunday's Level 8/9 Junior Olympic Division all-around and individual event finals.

On Saturday, the top 42 Level 10 Junior Elite athletes from each age division compete to determine the Level 10 Junior Elite Division all-around and event champions. The top 42 Level 8 and the top 42 Level 9 Junior Elite athletes compete on Sunday to determine the respective all-around and event champions.

Via USA Gymnastics.