In August 2011 Muki won the European Cup U20 in Berlin in the under 73 kilogram (161-pound) category. He won gold medals in February 2013 at the European Open in Tbilisi, Georgia, in June 2013 at the European Open Tallinn, and in October 2013 at the European Open Minsk in the under 73 weight class. In May 2014, he won the Baku Grand SlaminAzerbaijan in the under 73 kg category, and the following month he won another International Judo Federation World Tour gold medal, this time at the Havana Grand Prix in the under 73 kg category.
At the age of eight, he chose to focus on judo, which he had been practicing for four years, despite excelling in football for a Netanya junior soccer team, and also playing basketball and soccer.[19][16][20][21] He attended Tchernichovsky High School in Netanya.[2] As of June 2015 he still resided with his parents, for reasons of convenience and proximity to the Wingate Institute sports training facility.[21] He served in the Israel Defense Forces as a Sergeant in the Vehicle Division at the Sde Dov airbase.[22] He is a student at Reichman University, with a double major in Economics and Business Administration, and in the school's hall of fame.[23]
From the age of four, Muki has been coached by Israeli judoka Oren Smadja, who won the Olympic bronze medal in the under 71 kilograms (157 lb) weight category in judo at the 1992 Summer Olympics in Barcelona.[17][18][21][24] Smadja is also the national team coach, and Muki views Smadja as a fatherly figure.[21][25] His club is MaccabiNetanya, and he met future Israeli judoka world champion Yarden Gerbi there when he was four years old.[16][18] He noted in 2013: "It's important to me to serve the State as an athlete. This year, I got to play the national anthem in Georgia, Estonia, and Belarus, and last year in Germany. Every time the audience stands for the anthem, it's fun and brings me great pride".[26]
In April 2011 he came in fifth in the World U-20 Junior Championships in the under 73-kilogram (161-pound) category.[27] In August 2011 Muki won the European Cup U20 in Berlin in the under 73 kg category.[28] In September 2011, he came in third in the European U20 ChampionshipsinLommel, Belgium, in the under 73 kg category.[29] In December 2012, he won the Israeli Championship in the under 81 kilograms (179 lb) category in Ra'anana, Israel.[30]
Muki won a gold medal at the European Open in February 2013 in Tbilisi, Georgia, in the under 73 kg category.[31][32][33] He also won gold medals at the European Open Tallinn in June 2013, and the European Open Minsk in October 2013 in the under 73 weight class.[34][35][36][37] He won the Israeli Championship in the under 81 kg category in Ra'anana, Israel in December 2013.[38]
In May 2014, Muki won the Baku Grand SlaminAzerbaijan in the under 73 kg category.[39][40] In June 2014, he won another International Judo Federation World Tour gold medal, at the Havana Grand Prix in the under 73 kg category.[41][42][43] In October 2014, he was ranked number three in the world in his weight class, and in May 2015 he had moved up to number two in the world.[44]
In June 2015, representing Israel at the 2015 European Games in judo in the under 73 kg category in Baku, Muki won the first gold medal for Israel in the inaugural European Games, and in doing so won the 2015 European Judo Championship.[8][9][10][45][46] In the quarterfinals he defeated then-reigning European champion Dex Elmont of the Netherlands.[21] He defeated Nugzar Tatalashvili of Georgia in the final, throwing him for an ippon twenty-eight seconds prior to the end of their match, and after his victory he pointed with a smile at the Israeli flag on his judogi.[21][25][44] He became the first Israeli men's European Judo Champion since Ariel Ze'evi, who won the championship four times.[44] Muki received NIS 40,000 (approximately $10,500) from the Israel Olympic Committee for his achievement, the highest amount of any Israeli athlete, and a monthly stipend of NIS 8,500.[20][21][45][47]
In August 2016, Muki competed for the first time in his career for Israel at the 2016 Summer Olympics at the age of 24, two months after suffering two slipped discs in his lower back.[54][19] In the first round he defeated former European champion Rok Drakšič of Slovenia with an ippon. In the second round he beat Igor Wandtke of Germany. In the quarter-finals, Muki defeated Nicholas Delpopolo of the United States. In the semi-finals, Muki lost to Rustam Orujov of Azerbaijan, and subsequently he was also defeated by Lasha Shavdatuashvili of Georgia for the bronze medal. Muki finished in fifth place.[55][56][57][58][59]
On 7 October 2017, Muki competed at the 2017 Tashkent Grand Prix, his first competition since the 2016 olympics, and won the gold medal.[60][61][62]
On 27 April 2018, Muki took part in the European championshipsinTel Aviv and won the gold medal in the under 81 kg weight category.[63][64][11] In the first round he defeated Jonathan Allardon of France by ippon, in the second round he defeated Matthias Casse of Belgium by waza-ari. He went on to defeat László Csoknyai of Hungary by ippon in the quarter final and Aslan Lappinagov of Russia by shidos in the semi-final. In the final Muki defeated Sami Chouchi of Belgium by waza-ari in golden score.[65]
At the 2019 World Judo ChampionshipsinTokyo, Muki became world champion when he won the gold medal in the under 81 kg weight category.[66][67] Coming to the competition, Muki was ranked 2nd in the world and 5 out of his 6 matches that day, he won by Ippon. He won his first 4 matches by Ippon and in the semi-final he defeated Mohamed Abdelaal of Egypt by Waza-ari. In the final, Muki faced Matthias Casse of Belgium and won by Ippon due to 2 Waza-ari scores.[68]