Early career – 2008 Contreras started in weightlifting at the age of 14. and received an award of
RD$100,000 (approximately US$3,125 in May 2006). She dedicated the award to her mother and her coaches. Later that year, she won the silver medal at the 2006 Junior World Weightlifting Championship in snatch with 89 kg and bronze in total with 200 kg. With this she imitated her Cousin Wanda Rijo, who won three gold medals in the 1997 National Games. The
2006 Central American and Caribbean Games held at the
Colombian city of
Cartagena saw Contreras win the gold medal in snatch with 95 kg, the silver in clean and jerk with a 111 kg, and the gold medal in total with 206 kg in the
Lightweight (– 58 kg) division. Following her success in 2006, she was listed among the Dominican Republic newspaper
Diario Libres "Men and Women of the Year". She traveled to
Matanzas, Cuba, to take part at XXVI Manuel Suárez International Weightlifting Tournament winning the gold medal in the 58 kg division with a 92 kg mark in snatch, 117 kg in clean & jerk and 209 kg in total, all of them new records for the competition. Later that year, she was selected by the Dominican Republic Olympic Committee as the
flag bearer at the
2007 Pan American Games. In these games, she won the gold medal in the
under 53 kg category, setting three new records with 95 kg in snatch, 112 kg in clean and jerk, and 207 kg in total. After that winning she was promoted from
sergeant to
sergeant major. At the
2007 World Championships held in
Chiang Mai, Thailand, she failed her three attempts in snatch, two with 92 kg and the last with 93 kg. She marked 107 kg in clean & jerk ranking 12th and ended with no mark in total in the
under 53 kg category because of her snatch failure. In 2008, the Dominican Republic Youth Ministry awarded Contreras for her success in the sports field as a youth, and she was recognized once again in
Dario Libres "Men and Women of the Year", receiving a Silver Tray as one of the 10 finalist for the main award. The 2008 Dominican Republic Military Games saw Contreras win the 58 kg for the later crowned event champion, the National Army. In early March, she won three gold medals at the
2008 Pan American Championships, qualifying her for the next
Olympic Games. For her 2007 year-round performance, the San Pedro de Macorís Guild of Sport Writers awarded Contreras in May, as her province "Athlete of the Year". Before the Olympics, she had a two-month training in
Bulgaria, trying to recover her
legs strength. At the
2008 Summer Olympics, she ranked 5th with a total of 204 kg in the
53 kg category, after being trained by the Bulgarian coach Konstantin Darov.
2009 controversy – 2011 After competing at the Olympics, Contreras tested positive for a
CERA enhancer drug, and faced a two-year suspension, One month later, she won the silver medal at the
2010 Pan American Weightlifting Championships, after losing the gold medal to the Ecuadorian
Alexandra Escobar in the under 58 kg category. Due to stress-related weight loss, Contreras began competing in the 53 kg category later in 2010, and she won three gold medals at the
2010 Central American and Caribbean Games held in
Mayagüez, Puerto Rico, setting new records in snatch with 96 kg, 117 kg in clean and jerk, and 213 kg total weight. She received the support from the telephone company
Tricom to train in
Bulgaria as part of the company's "Tricom Sport Project", Competing at the
2011 World Weightlifting Championships in Paris, France, she won the silver medal with a 95 kg snatch lift in the
– 53 kg, after winning she gave the credit to her coaches Héctor Domínguez, Félix Ogando and
Belarusian Liavontsi Hancharenka. Among many other military athletes, she was awarded for their performance during all 2011 by the Dominican Army Commander,
Major General Pedro Antonio Cáceres Chestaro, during the year-end army
Christmas celebration.
2012 In May, Contreras raised her
body weight to 55.7 kg and competed in the under 58 kg category at the Pan-American Championship held in
Antigua Guatemala, Guatemala winning the bronze medal with a total lifted of 206 kg. The Dominican Republic Weightlifting Federation awarded Contreras with her 6th "Female Weightlifting athlete of the Year", and also being considered by the national Olympic Committee for the National Athlete of the Year Award. She finished in 4th place after the winner,
taekwondo practitioner Gabriel Mercedes,
table tennis player
Wu Xue and
volleyball player
Bethania de la Cruz. After the National Federation gave her one of the
two entries given to the National Olympic Committee by the
International Weightlifting Federation to participate in the
Olympic Games, Contreras was set to practice under the guidance of
Belarusian Leonte Goncharenko. Even though she was lifting 100 kg in snatch and 120 kg in clean and jerk and one of her country's biggest hope for an Olympic medal, she failed her three attempts for 94 kg in snatch falling out of the competition.
2013 She participated in the Women's Sports Festival held in Santo Domingo taking the competitors sports oath, her first competition after the London Olympics and she confessed that she felt that she could overcame what happened there. Contreras, that was awarded weightlifting Most Valuable Athlete, lifted 96 kg in the 53 kg snatch competition to win the gold medal. After helping the Dominican Army to win the weightlifting competition from the National Military Games with gold in the 53 kg, she took part in June in the Panamerican Championships same division, winning the snatch gold medal with 92 kg but she tried to set a new Pan American record with 97 kg and failed. She earned the silver medal with 110 kg in clean and jerk after the 111 from Colombian Rusmery Villar and the gold in total with 202 kg.
2014 Contreras was awarded 2013 athlete of the year in weightlifting by the National Olympic Committee and along with
Brayelin Martínez and
Yenebier Guillén as the only females awarded by the Guild of Sport Writers for their success in the previous year. Competing at home in the
Pan American Weightlifting Championships and after spending 24 hours without food to reach her category weight limit, 58 kg, she won the gold medal in snatch setting a new Pan American record with 97 kg and gold in total with 207 kg. She won the clean and jerk silver with 110 kg after losing by bodyweight to the Colombian Rusmeris Villar with the same lift. Her coach confessed that she made the same mistake with her arms in her two fails with 113 trying to set a new record. Contreras felt disappointed with herself because she was in great form for the competition, but she said that always prepares herself physically and under God's willing. She traveled then traveled to Mexico to compete in the 58 kg division of the first
Pan American Sports Festival, winning the gold medal in clean and jerk with 107 kg and silver in snatch with 90 kg. She participated in the
2014 World Weightlifting Championships in
Almaty, Kazakhstan, finishing in the eleventh position with 87 kg in snatch, 105 kg in clean and jerk and 192 kg in total. Even though she could lift more weight, her main goal was to prepare for the upcoming Central American and Caribbean Games and cumulate points for the
2016 Summer Olympics qualification. Contreras went to the
2014 Central American and Caribbean Games as one of the main medal hope, she was trying to win the gold and set new records working with her coaches Héctor Domínguez and Félix Ogando.
2015 During the
2015 Pan American Games in
Toronto, she was training without pain from her previous injury after having surgery to correct a lumbar hernia in January but could not reach the level of her two previous Pan American Games golds in 2007 and 2011, failing three times to lift 88 kg in the
53 kg snatch. She also saw her clean and jerk record fell in the competition to the later gold medalist, the Colombian Rusmery Villar, improving the mark from 112 to 115 kg. Team partner and bronze medalist
Yafreisy Silvestre later revealed that Contreras was suffering from an injured leg before the competition. Contreras was set to compete in the 58 kg division from the
World Weightlifting Championships, and that division would be her new one onwards. She ranked ninth with 95 kg in snatch, 116 kg in clean and jerk and 211 kg in total. ==Major results==