Azem Maksutaj is a Swiss former kickboxer who competed in the lightweight, welterweight, middleweight, super middleweight, light heavyweight, cruiserweight and heavyweight divisions. Originally from Kosovo, he relocated to Switzerland at an early age where he began training in Muay Thai at fifteen. After capturing the Swiss national title at lightweight during his first year of competition in 1992, he then went on to win European and world honours 1994 while fighting around the 77 kg super middleweight mark. The late 1990s saw Maksutaj move between light heavyweight and cruiserweight, taking five world titles in those divisions, before eventually making the jump to heavyweight in 2001 where he spent the remainder of his career, acting as a journeyman in the K-1 promotion while also winning another four world titles.
Andreas "Andy" Hug was a Swiss karateka and kickboxer who competed in the heavyweight division. Considered to be one of the greatest heavyweight kickboxers of all time, Hug was renowned for his ability to execute numerous kicking techniques rarely seen in high-level competition. Although he was usually smaller than his opponents, standing at 1.80 m and being barely a heavyweight, weighing around 98.0 kg in his prime, he made up for his lack of size with his tremendous athleticism and speed. A southpaw, his trademark kicks included the axe kick and the "Hug Tornado", a low spinning heel kick targeting his opponents' thighs.
Peter Aerts is a Dutch semi-retired kickboxer. Known for his devastating high kicks, which earned him the nickname "The Dutch Lumberjack", he is widely considered to be one of the greatest heavyweight kickboxers of all time.
Glaube Araújo Feitosa is a Brazilian former kickboxer and a kyokushin full contact karate practitioner who was competing in K-1. In 2005, Feitosa won K-1 World Grand Prix 2005 in Las Vegas tournament and was a K-1 World Grand Prix 2005 finalist. He has gone the distance with some of the top fighters in his time, such as Peter Aerts, Remy Bonjasky, Semmy Schilt and Errol Zimmerman. An accomplished karate fighter, he was known for his use of the "question mark kick," utilizing the technique in several knockout victories in his career. Feitosa also holds wins over Cheick Kongo, Alistair Overeem, Ruslan Karaev, and Paul Slowinski.
Ondřej Hutník is a retired Czech Muay Thai kickboxer. He is a former SUPERKOMBAT Super Cruiserweight Championship title challenger.
Xhavit Bajrami is a Swiss former kickboxer who competed in the heavyweight division. A Seido karate practitioner and Andy Hug student, Bajrami built up an undefeated record domestically before he was recruited by K-1 where he won the K-1 Braves '99 tournament and finished as runner-up in two other tournaments. He is also a two-time Muay Thai world champion, having won the ISKA World Super Heavyweight title in 2004 and the WKN World Super Heavyweight strap in 2010.
Errol Zimmerman is a Curaçaoan-Dutch kickboxer, representing the Hemmers Gym in Breda, Netherlands. He is K-1 World Grand Prix 2008 in Amsterdam and SUPERKOMBAT Fight Club tournaments champion. Zimmerman is also former Glory Heavyweight Championship and K-1 Super Heavyweight Championship challenger. In 2011 WIPU voted him the Kickboxer of the Year.
Kyotaro Fujimoto is a Japanese former professional boxer who competed from 2011 to 2019 and a kickboxer. He began competing again as a professional kickboxer in 2021.
Ewerton Teixeira is a Brazilian professional kickboxer, mixed martial artist, and Kyokushin Kaikan karateka. Teixeira obtained his first K-1 title in 2008 at K-1 World Grand Prix 2008 in Fukuoka by beating Keijiro Maeda in the final. He is training K-1 at the Ichigeki Academy Kyokushin Kaikan in Tokyo, Japan. Despite the short career for a kickboxer, Teixeira has notable wins against K-1 legends: Jerome Le Banner, Errol Zimmerman and Musashi.
Andrews Nakahara is a Brazilian professional mixed martial artist, kickboxer and kyokushin karateka currently signed with K-1. He made his MMA pro debut against Kazushi Sakuraba at the Dream 2: Middleweight Grand Prix 2008 First Round.
Mauricio "Baboo" Da Silva is a Brazilian kyokushin kaikan full contact karate practitioner and former professional kickboxer and mixed martial artist. He is a professional coach and trainer of K-1 and MMA, who has trained a number of world class fighters including Francisco Filho, Glaube Feitosa, Andrews Nakahara, Ewerton Teixeira, Ray Sefo, Aleksandr Pitchkounov, Takumi Sato, Jan Soukup, Kou Tasei, Jan Nortje, Doug Viney, Mighty Mo (kickboxer) and Akebono Taro. From 1998 to 2004 he worked as the trainer and sparring partner for Francisco Filho. He lived in Tokyo, Japan from 2005 to December 2010 and trained fighters from the IKO1 Kyokushin - Team Ichigeki and other fighters from visiting teams at the Ichigeki Plaza. He fought in the K-1 PREMIUM 2003 Dynamite!! and also in the Ichigeki events in Japan.
Petr Vondráček is a heavyweight kickboxer. He is a former WKA World Champion.
Yuji Nashiro (名城裕司) is a Japanese kickboxer who competes in the welterweight division.
Masahiro Yamamoto is a Japanese kickboxer who competes in the lightweight division. After beginning his career as a featherweight in 2002, Yamamoto became a mainstay in the All Japan Kickboxing Federation and first challenged for the AJKF Featherweight Championship in December 2004 when he fought to a draw with Genki Yamamoto. He then went on a hot streak in 2005, winning the IKUSA 2005 –60 kg Grand Prix in the process, and was given another chance at the AJKF Featherweight title in January 2006 when he beat Genki Yamamoto in a rematch to take the belt. The following years saw Yamamoto move up to lightweight and have more domestic success as he took the AJKF's Best of 60 kg Tournament 2007 and the Krush Lightweight Grand Prix 2009 before he emerged internationally with the It's Showtime promotion. He lost to Sergio Wielzen in his first attempt at the It's Showtime 61MAX Championship in December 2010 but came back to win the belt in July 2012 by defeating Javier Hernandez.
Michael Thompson is an English former karateka and kickboxer who competed in the cruiserweight and heavyweight division. After a long and distinguished career in Kyokushin, in which he won the British Open four times, the Commonwealth Championships in 1988 and the European Championships in 1991 as well as competing three times in the World Open, Thompson later switched to Seidokaikan and reached the final of the 1994 Seidokaikan Karate World Cup. During his time as a Seidokaikan competitor, he also fought as a professional kickboxer in K-1, amassing a 6–5 record and becoming the WKA European Super Cruiserweight Champion.
Kengo Shimizu, is a Japanese middleweight kickboxer competing in RISE. He is the former SHOOTBOXING and RISE Heavyweight champion.
Jean Rivière is a Canadian former Kyokushin karateka, kickboxer and mixed martial artist. A heavyweight competitor fighting out of Montreal, Rivière reached the semi-finals at the 5th Kyokushin World Open in 1991 and later embarked on a career in the K-1 kickboxing promotion and the burgeoning MMA scene of the mid-1990s.
Seiji Isobe is Japanese Karate instructor residing in Brazil. He is a member of the IKO1 's international committee and is the General Manager of the South American Regional Federation. He holds a rank of 8th Dan Black in Kyokushin Karate.
Alejandro Navarro is a Spanish Full-contact Karateka. He is a 16-time Kyokushin European Champion, of which Navarro has won the Open Championship nine times. He has also once won the 2013 World Cup.
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