She was most successful in the 2002–03 season, when she was the first German to win the women's overall Biathlon World Cup.

[1] Beck's father, Martin Glagow, is a former army officer and ski technician: he waxed Martina's skis until the end of the 2004–05 season, and was also a wax technician for the British biathlon team from 2000 until his retirement in 2011.

[2][3] Although Beck stands only 1.58 m (5 ft 2 in) tall, she was a strong skier, but was renowned for her shooting ability: she was regularly among the female athletes with the highest accuracy rate, leading the shooting statistics in the 2003–04 season with a rate of 89 percent.

Later, she became the first German biathlete to win the women's Biathlon World Cup in the 2002–03 season, alongside the pursuit World Cup; in 2005–06, she finished third in the overall standings and won the mass start standings.

During the 2006 Winter Olympics in Turin, Beck won three silver medals: one in the sprint competition, one in the pursuit, and one in the relay.