John Spezzano has been a student of martial arts for almost 40 years, and a student of strength for over a decade. Covering as many combat bases as possible, John has instructor certificates in Filipino Martial Arts, Pencak Silat and Jeet Kune Do from Guro Dan Inosanto, Muay Thai from Ajarn Chai Sirisute, Wing Chun from Sifu Francis Fong, a Silver Glove in Boxe Francaise Savate from Professor Nicolas Saignac and a Brown Belt in Brazilian Jiu Jitsu from Professor Shawn Williams.

From 1995-2009 John was a staff instructor at the Inosanto Academy of Martial Artsin Los Angeles, teaching classes in all of the above listed arts. In 2010, he started the Muay Thai and strength programs at Five Star Martial Arts in Los Angeles, where he taught until the end of 2016.

John completed his level 1 kettlebell certification in 2008. In 2010, Black Belt Magazine published his book The Martial Arts / Kettlebell Connection,one of the first publications available to specifically help martial artists improve their combat sport performance through the use of the kettlebell. John completed the level 2 kettlebell certification in 2012, and re-certified in 2014. He was promoted to StrongFirst Team Leader in 2016, and now helps teach the next generation of kettlebell instructors. In August 2017, John opened Source 1 Martial Arts and Fitness in downtown Los Angeles.