Choi Sung-hoon

Akiyama faced Sherif Mohamed at ONE Championship 109: King of the Jungle on February 28, 2020. Akiyama won the fight via knockout in the first round, his first stoppage via strikes in nearly 13 years.

After three years from his previous bout, Akiyama announced his contract with ONE Championship. Akiyama faced Agilan Thani in a co-headliner bout at ONE Championship: Legendary Quest on June 20, 2019. He lost the bout via unanimous decision

After another year away from the sport, Akiyama returned to face Alberto Mina on November 28, 2015 at UFC Fight Night 79. He lost the back-and-forth fight via split decision.

He names Heavyweight Champion boxer Mike Tyson as his hero and holds a University degree in Commerce. He is close friends with South Korean actor Jang Keun-suk. In September 2015, Akiyama also appeared as a guest on 2 Days & 1 Night.

After over two and a half years away from the sport, Akiyama returned from his self-imposed hiatus on September 20, 2014 at UFC Fight Night 52. He was originally scheduled to face Kyle Noke on the card. However, Noke was forced out of the bout with a knee injury and replaced by Amir Sadollah. Akiyama won the fight via unanimous decision.

Akiyama faced Jake Shields on February 26, 2012 at UFC 144. He lost the fight via unanimous decision (30-27, 30-27, 30-27). During the bout, Akiyama was able to utilize multiple judo techniques which was praised as the main highlights of the fight; despite losing the decision.

Akiyama was expected to face Thiago Alves on July 21, 2012 at UFC 149. However, Akiyama was forced out of the bout with an injury.

Akiyama was briefly scheduled to face Chael Sonnen on March 19, 2011 at UFC 128, but, due to Sonnen's suspension, the fight was scrapped. Akiyama was later scheduled to face Nate Marquardt at the same event, but pulled out due to the 2011 Tōhoku earthquake and tsunami and was replaced by Dan Miller.

Akiyama was defeated by Vitor Belfort at UFC 133 via KO (Punches) in the first round. This defeat marked the third straight loss for Akiyama in the UFC. Following the fight, Dana White stated that Akiyama most likely would not be cut from the organization if he agrees to move down to welterweight. As of September 3, 2011, Akiyama has stated he will move down a weight class, allowing him to stay in the UFC. On November 3, 2011, a picture of Akiyama had circled the web of his body frame as a welterweight.

Choo Sung-hoon's great-grandfather, Choo Jeong-won, was born in Jeju County, Jeollanam-do, Korean Empire (now Jeju City). During the Imperial Japanese occupation of Korea, Choo Jeong-won and his family sailed to Japan and adopted Japanese names to help settle in. In March 2009, Akiyama married famous Japanese fashion model Shiho Yano (also known as SHIHO in Japan) whom he had been dating since January 2007. The couple have a daughter, Choo Sarang, who was born on October 24, 2011. Akiyama and Sarang starred in the reality show, The Return of Superman, covering their father-daughter relationship.

Akiyama joined Xtreme Couture for the month of October 2009 to work on his striking skills. Akiyama was expected to face MMA legend and former PRIDE Middleweight Champion Wanderlei Silva on February 21, 2010 at UFC 110, but Silva instead faced British striker Michael Bisping on the card, winning via unanimous decision. At the Post-fight conference, UFC President Dana White stated that Akiyama had requested to fight Silva for a while and has refused to fight other opponents, after which both fighters verbally agreed to fight.

Akiyama was expected to face Silva on July 3, 2010 at UFC 116. Wanderlei had to pull out on June 22, 2010 due to fractured ribs suffered in training. Chris Leben was chosen as a replacement. Despite controlling the majority of the fight with effective strikes and solid Judo takedowns, Akiyama became fatigued after the first round and lost via triangle choke with just twenty seconds left in the third round. His loss to Leben was his first official loss in five years.

Akiyama lost to Michael Bisping on October 16, 2010 at UFC 120 by unanimous decision. In preparation for his fight with Bisping, Akiyama switched to Jackson’s Submission Fighting in Albuquerque, New Mexico. It is unclear whether the switch is permanent. Even though Akiyama lost to Bisping, he rocked him in the first round. He earned his third "Fight of the Night" honors. He has now earned "Fight of the Night" honors for all three of his UFC appearances.

On February 24, 2009 it was announced on the official UFC website that Akiyama had signed a deal with the company. Even though he suffered a broken orbital bone during the start of round two, Akiyama went on to beat UFC veteran Alan Belcher at UFC 100 on July 11 by split decision (30–27, 28–29, 29–28). It was the 1st fight in Akiyama's career that went to the judges' score cards. The bout was also awarded "Fight of the Night" honors, granting both fighters a record-setting $100,000 bonus each.

On May 30, 2009 Akiyama opened a new gym in Tokyo, Japan. The 'Akiyama Dojo' has Judo and MMA halls, 30 tatami mats and three octagonal cages.

Akiyama was cleared from his FEG-induced suspension and FEG announced that Akiyama would return to K-1 Hero's in Seoul, on October 28, 2007. His opponent was Denis Kang, who was the finalist of PRIDE Bushido Grand Prix 2006 and making his debut in Hero's. Though he was an underdog, Akiyama beat Kang by KO in the first round.

On December 31, 2007, Akiyama faced Kazuo Misaki at Yarennoka!. The rules of the match stated that kicks to the head of a downed opponent would not be allowed. Late in the first round Misaki knocked down Akiyama with left hook, and as Akiyama struggled to his feet, Misaki delivered a lunging kick to the face which knocked Akiyama out. The match was ruled a knockout victory for Misaki, but Akiyama contended that one or both of his hands were on the mat at the time of the kick, which would make the kick a foul under the Yarennoka! rules. After reviewing video of the knockout, the Yarennoka! executive committee agreed; the official result was changed to a no contest.

In K-1 Premium 2006 Dynamite, Akiyama fought the legendary Kazushi Sakuraba in the main event. During the match, Sakuraba called to the referee saying "[Akiyama is] Slippery!" Akiyama went on to win the match with a referee stoppage. This created a controversy amongst MMA fans in Japan, assuming Akiyama was using some sort of body oil or lubricant, banned in K-1 rules.

Akiyama's mixed martial arts debut was in the K-1 Premium 2004 Dynamite event on December 31, 2004, where he defeated boxer Francois Botha by armbar submission in the first round. His first defeat was to Jerome LeBanner, who knocked him out with knees in his second fight at the HERO'S 1 event on March 26, 2005, although LeBanner is a heavyweight that came into the fight at 262 pounds (119 kg), while Akiyama came into the fight at 189.5 pounds (86 kg). He has notable wins against Tokimitsu Ishizawa, Taiei Kin, Kestutis Smirnovas and Melvin Manhoef. Akiyama defeated Melvin Manhoef at the Hero's light-heavyweight Grand Prix 2006 final round, and gained the champion belt.

Representing Japan, Akiyama won the Gold Medal at the 2002 Asian Games defeating Ahn Dong-Jin of South Korea in the finals.

Akiyama was also accused of wearing slippery gear by former world and Olympic champion Kenzo Nakamura when they fought at the world championship trials in 2002.

Representing South Korea, Choo won the Gold Medal at the 2001 Asian Judo Championships.

Akiyama defeated three opponents from France, Mongolia and Turkey to reach the semi-finals of the 81 kg Light Middleweight division. However, all three opponents claimed that Akiyama had a slippery judogi. Wearing a reserve gi, Akiyama lost two games in a row (semifinal and 3rd-place match) and missed the medal.

Yoshihiro Akiyama (秋山 成勲 ) (born July 29, 1975), also known as Sung-hoon Choo (추성훈 ) , is a Japanese mixed martial artist and judoka. Akiyama won the gold medal at the 2001 Asian Championships for South Korea, and for Japan at the 2002 Asian Games. A fourth-generation Japanese of Korean descent, he acquired Japanese nationality in 2001. He is the former K-1 HERO's Light Heavyweight Grand Prix Tournament Champion.