Gallery

David Koczkas (15) paddles during a frequency and amplitude training session using an indoor canoeing pool at the Canoe & Kayak Club Komarno in Komarno, Slovakia on January 7, 2016.

David Koczkas (15) strains as he completes a sit-up exercise at the Canoe & Kayak Club Komarno in Komarno, Slovakia on April 19, 2016.

Prior to starting an endurance training session on water, David Koczkas (15) warms up in the gym at the Canoe & Kayak Club Komarno in Komarno, Slovakia on January 7, 2016.

David Koczkas (15) and Richard Zilizi (15) run together during their pre-training warm-up routine along the river Vah in Komarno, Slovakia on Jul 16, 2015.

David Koczkas (15) and Richard Zilizi (15) are captured during their pre-training stretching routine at the Canoe & Kayak Club Komarno in Komarno, Slovakia on Jul 16, 2015.

David Koczkas (15) and Richard Zilizi (15) paddle on the river Vah during their training in Komarno, Slovakia on Jul 16, 2015.

Oliver Koczkas (47) follows David Koczkas (15) and Richard Zilizi (15) on a motor boat during their training in Komarno, Slovakia on July 16, 2015.

Oliver Koczkas (47), David's father and coach, holds the stopwatch as he watches the C2 boat David and Richard Zilizi (15) finish a timed lap during a training session on river Vah in Komarno, Slovakia, on April 19, 2016.

Oliver Koczkas (47) shouts at David Koczkas (15) and Richard Zilizi (15) as they complete a timed lap during a training session on river Vah in Komarno, Slovakia, on April 19, 2016.

The C2 boat of David Koczkas (15) and Richard Zilizi (15) participates in a simulated race on Nitra river in Komarno, Slovakia, as a part of their training program on April 19, 2016.

Richard Zilizi (15) and David Koczkas (15) carry their C1 boats to a storage room following their training session on river Vah in Komarno, Slovakia on July 16, 2015.

Oliver Koczkas (47) and David Koczkas (15) have a post-training argument in the boat storage room of the Canoe & Kayak Club Komarno in Komarno, Slovakia on April 19, 2016.

David Koczkas (15) and Oliver Koczkas (47) are pictured in the living room of their home, in Komarno, Slovakia on September 12, 2015. The scene was shot in the evening before David took part in the ICF Canoe Marathon World Championships in Gyor, Hungary.

Team Slovakia, consisting of the coach Oliver Koczkas (47), and riders Richard Zilizi (15), Istvan Bainai-Toth (16) and David Koczkas (15), leaves a pre-race meeting at the ICF Canoe Marathon World Championships in Gyor, Hungary on September 13, 2015.

David Koczkas (15) and Oliver Koczkas (47) wait at the Team Slovakia's van to be called to a pre-race presentation at the ICF Canoe Marathon World Championships in Gyor, Hungary on September 13, 2015.

Richard Zilizi (15) prepares the C2 boat he shares with David Koczkas (15) prior to their 11 mile race at the ICF Canoe Marathon World Championships in Gyor, Hungary on September 13, 2015.

David Koczkas (15) and Richard Zilizi (15) are seen chasing their competitors while they complete a portage section of the race course at the ICF Canoe Marathon World Championships in Gyor, Hungary on September 13, 2015.

David Koczkas (15) smashes his paddle on the water surface as he, together with Richard Zilizi (15), cross the finish line of the 11 mile long race course at the ICF Canoe Marathon World Championships in Gyor, Hungary on September 13, 2015.

The Koczkas family - David (15), Oliver (47) and Andrea (44), is portrayed in the living room of their home, in Komarno, Slovakia on September 12, 2015. The scene was shot in the evening before David took part in the ICF Canoe Marathon World Championships in Gyor, Hungary.

David Koczkas (15) is seen in his room on September 12, 2015, as he packs his racing kit into a backpack, while preparing for his race at the ICF Canoe Marathon World Championships in Gyor, Hungary the following day.

David Koczkas (15) leaves his house in Komarno, Slovakia, in the early morning of September 13, 2015.

Oliver Koczkas (47) drives his car to Komarno, Slovakia, where he is to lead a training session with his son, David Koczkas (15), on April 19, 2016.

A morning aerial view of the racing area, shot during the day 2 of the National Youth Championships of Slovakia in Piestany, Slovakia, on August 8, 2015.

A detail seen in the storage compartment of a car during the day 1 of the National Youth Championships of Slovakia in Piestany, Slovakia, on August 7, 2015.

David Koczkas (15) and Richard Zilizi (15) compete in a C2 race on day 1 of the National Youth Championships of Slovakia in Piestany, Slovakia, on August 7, 2015.

A general view of a race on day 1 of the National Youth Championships of Slovakia in Piestany, Slovakia, on August 7, 2015.

David Koczkas (15), Richard Zilizi (15) and Oliver Koczkas (47) analyse their performance following a C2 sprint on the day 1 of the National Youth Championships of Slovakia in Piestany, Slovakia, on August 7, 2015.

David Koczkas (15), portrayed among his friends from the Komarno Canoe & Kayak Club, cheers for his friend, at the time competing in a C1 race on the day 2 of the National Youth Championships of Slovakia in Piestany, Slovakia on August 8, 2015.

Richard Zilizi (15) strains his face while he has his shoulder massaged, following a C1 race on the day 1 of the National Youth Championships of Slovakia in Piestany, Slovakia on August 7, 2015.

Oliver Koczkas (47) watches his son David Koczkas (15) as he competes in a C1 race on the day 1 of the National Youth Championships of Slovakia in Piestany, Slovakia on August 7, 2015.

David Koczkas (15) crosses the finish line of a 200m C1 race, and becomes the national champion in his age category of this discipline. The race took place on the day 1 of the National Youth Championships of Slovakia in Piestany, Slovakia on August 7, 2015.

David Koczkas (15) receives a congratulatory hug from his father and coach Oliver Koczkas (47), following his win in a C1 race on the day 2 of the National Youth Championships of Slovakia in Piestany, Slovakia on August 8, 2015.

A celebratory scene at the results board, captured on the day 1 of the National Youth Championships of Slovakia in Piestany, Slovakia on August 7, 2015.

David Koczkas (15) stands on the podium after finishing first in a C1 race on the day 1 of the National Youth Championships of Slovakia in Piestany, Slovakia on August 7, 2015.

A C4 boat riders, consisting of David Koczkas (15), Richard Zilizi (15), Istvan Banai-Toth (16) and Samuel-Daniel Sykora (15), stand on the podium after receiving medals for their win in the C4 race. The four, all based in Komarno, Slovakia became champions in their age category of the discipline for the first time. The scene was shot on the day 1 of the National Youth Championships of Slovakia in Piestany, Slovakia on August 7, 2015.