Beck (26) had concentrated on the standard duathlon distance of a 10km run, 40km cycle and 5km run since she began the sport in 2003.
She has a wide experience at the world championships with her best performance a fourth in Belgium at the under-23 event in 2004.
Beck tried the long-distance powerman event for the first time in Weyer, Austria, last year and won the international event.
This encouraged Beck to concentrate on the longer events and she will compete in the powerman world championships in Zofingen, Switzerland, in early September.
The world powerman event consists of a 10km run, 150km cycle and 30km run.
Beck has reduced her time at the Pitt St dental surgery to 33 hours a week as she prepares for the world championships.
She does not start work until 2pm and has the morning to fit in the 17 hours a week she spends running or on her bike.
"It works really well," Beck said. "It enables me to train in the daylight instead of squeezing in training after work," Beck said.
Beck has built more distance work into her training under new coach Tim Brazier and she proved that it is working when she finished runner-up to Katherine Anton (Whangarei) in the selection race last weekend.
She will represent New Zealand at the elite standard distance in the United States at the end of September.
Beck completed the race at Ashley Forest, Rangiora, in 2hr 15min 10sec to qualify for her third elite world standard championships.
She finished 15th in Hungary in 2007 and 14th in Italy last year.
Also competing at the world standard championships in the United States are Lindsay Dey in the men's 60 to 69 grade and Paul Gough in the men's 40 to 44 grade.
Dey finished runner-up in the selection race at Rangiora in 2hr 32min 51sec. He will also contest the world triathlon championships in Australia.
