Muramoto is from Nagasaki, Nagasaki and began judo at the age of 6.[1] He belonged to Asahi Kasei after graduation from Tenri University in 1999.
Muramoto was good at Uchimata and Harai goshi.[1]
In 2000, he won a gold medal at the Asian Championships held in Osaka, Japan. He was also participate All-Japan Championships 8 times. He was expected to get medal of Olympic Games or World Championships but could not participate by the trouble of the knee since 1995.[1]
Muramoto retired in 2007. Now, he has coached judo at Osaka University of Health and Sport Sciences since 2009.
- All-Japan high school Championships (+95 kg) 1st
- Inter-highschool championships (+95 kg) 1st
- Kodokan Cup (+95 kg) 3rd
- All-Japan Selected Championships (+100 kg) 3rd
- All-Japan University Championships (Openweigh) 1st
- Jigoro Kano Cup (+100 kg) 3rd
- World Masters Munich (+100 kg) 3rd
- All-Japan Selected Championships (+100 kg) 2nd
- All-Japan Selected Championships (+100 kg) 2nd
- All-Japan Selected Championships (+100 kg) 2nd