Sara Kolak was born in Koprivnica on 22 June 1995. She made her first athletic steps in elementary school, where her gift was recognized by a professor of physical education. She started throwing the small ball in sixth grade and in that category she quickly started to compete and achieve good results. The next year she was the best thrower in Erste Blue League and the logical sequence was the throwing discipline as she joined Athletic Club “Sloboda” from Varaždin with Stjepan Novoselec as a  coach.

Following her very good performance at cadets’ championship in the next few years, the next step was to join Kvarner Club in Rijeka for better training conditions. As a high school student in different city, she continues to train javelin throw in Rijeka with her next coach Petar Kurtović. At the beginning of 2013, as a junior, Sara appeared at European and World Junior Championships.

At the European Junior Championship in 2013  in Rieti, Italy she won a bronze medal with 57.79 meters, setting her personal record and improving the Croatian national junior and senior record by 99 centimeters. Soon after her first junior medal, Sthe first problems with the back and shoulder injury started. Due to the injury she missed the rest of the season.

In May 2014,  Sara started working with her new coach Andrej Hajnšek and she moved to Celje, Slovenia but continued to perform as a member of Rijeka »Kvarner» Athletics Club.  After a relatively quick recovery, Sara won a new bronze medal at the 2014 World Junior Championships in Eugene, Oregon.  At the end of the competition her javelin flew to  55.74 meters,  which was 60 centimeters better than Polish Marceline Witek.

After her second bronze medal, the shoulder pain returned, and in October 2014 she was forced to undergo a surgery on her right shoulder in Krapinske Toplice. After that Sara was faced with a painstaking physical therapy and a long and difficult recovery throughout the whole 2015 season.

European bronze and Olympic gold medal

At the beginning of 2016, after one-year of recovery, Sara started to train again and officially moved to senior national team.
In the open championship of Slovenia, on February 29, 2016 she threw her new national record 60.24 m , which was 2.45 meters better than the last one.

As a member of the Rijeka AK “Kvarner”,  she switched the norm (57.50m) for the European Championship the same year in Amsterdam and at the same time she became the first Croatian to throw the javelin over 60 meters. This success is even more greater because it happened at the first championship after her shoulder injury and 15 months without proper training.

On the open championship in Split, Croatia on March 6, 2016, she improved her Croatian record and set a new one with 62.75 m, thus achieving the Olympic norm and becoming the 11th Croatian athlete to appear at the Summer Olympics 2016 in Rio de Janeiro, Brazil.

Beside this great success, Sara performed at the European Winter Throwing Cup in Arad, Romania where she won a silver medal with a throw of 58.11 meters.

The Olympic Games’ norm has been achieved and preparations for the 2016 European Championship in Amsterdam have started. At the beginning of July,  Sara was among the 12 best European woman javelin throwers. In the third series of the finals the javelin stopped at 63.50 meters, improving the Croatian national record again and winning the new bronze medal for Croatia, Sara’s first medal in seniors’ competition. In Amsterdam, Sara’s hit was better than the one from world champion Katharina Molitor and the double Olympic winner and world recorder Barbora Špotakova.  Sara announced great upcoming results as a senior and the Olympic Games in Rio de Janeiro were just around the corner.
Although she came to Rio de Janeiro as a debutant, she justified all his previous achievements. The Olympic championship went slower in the first few series with two hits of 55.68 and 55.86 meters and Sara held 15th place overall. In the third series all came back and the javelin flew to 64.30 m, a new Croatian national record. With this last hit she secured the 3rd place and appearance in the Olympic finals.

In the fourth series at the very end of the Olympic Games, the javelin flew even to amazing  66.18 m,  a new personal and state record and the 5th gold medal for Croatia at the OI 2016 in Rio. The president of the IAAF Sebastian Coe, proclaimed Sara Kolak as the greatest surprise of the entire athletics program of the Olympic Games in Rio de Janeiro.