Mattie trains at All Olympia Gymnastics Center, AOGC for short, under Galina Marinova and Artur Akopyan. Galina is a two-time Olympia who competed for Bulgaria in the 1980 and 1984 Olympic Games. Galina is also an Olympic rated judge. Artur competed for the USSR at the 1980 Moscow News competition, the 1981 World Championships, and the 1983 World Championships. Artur was also the first gymnast to compete a Tsuk double twist on vault! Mattie also trains alongside several talented athlets who you can find more about below.

Samantha Shapiro was born on May 19, 1993. She was a member of the 2006-2007 Junior National Team, 2007-2008 Junior National Team, and 2008-2009 Junior National Team! Samantha made her elite debut at 2006 U.S Nationals in St. Pual, MN where she placed 13th in the All-Around. The following year Samantha traveled to San Jose, CA where she earned a silver medal at the National Championships and the gold medal on balance beam. She competed at the 20007 Gymnix International Competition in Montreal, CAN where she earned the gold medals on bars, beam, and the all around. Samantha repeated her silver medal placement at US Nationals in 2008. In 2009 Samantha was named to the USA delegation that traveled to Montreal, CAN for the Gymnix World Cup where she competed on Uneven Bars. Although an injury prevented Samantha from competing at the National Championships, she was petitioned on to the 2009-2010 National Team.