Lachlan Giles' martial arts journey began during his teenage years, inspired by Jet Li's dynamic performances in martial arts films. Initially enrolling in kung fu classes, Giles' trajectory shifted dramatically after witnessing Royce Gracie's groundbreaking Brazilian Jiu-Jitsu display at UFC I. This pivotal moment prompted Giles to pursue Brazilian Jiu-Jitsu training, marking the start of his distinguished grappling career.

Giles began his Brazilian Jiu-Jitsu training under Tyrone Crosse, who guided him from white to purple belt. Following a knee injury, Giles returned to training under John Simon, who awarded him both his brown and black belts. Additionally, Giles refined his technical skills and strategic approach through extensive training with Thiago Stefanutti.

Lachlan Giles gained global recognition at the 2019 ADCC World Championship with an extraordinary performance in the absolute division. Competing at just 77kg, Giles submitted three significantly larger opponents—Kaynan Duarte, Patrick Gaudio, and Mahamed Aly—using precise heel hook submissions. This remarkable achievement earned him the nickname "The Giant Slayer," highlighting the effectiveness of superior technique and strategic execution over size and strength.

For over a decade, Giles has served as head coach at Absolute MMA St Kilda in Melbourne, Australia. Renowned for his cerebral coaching style, Giles emphasizes specific sparring, detailed question-and-answer sessions, and systematic problem-solving drills. His innovative approach has produced notable athletes, including Craig Jones and Livia Gluchowska. Giles frequently conducts international seminars, teaching distinctive frameworks such as his "wedges" guard passing system and comprehensive half-guard methodology.

Lachlan Giles is highly regarded for his instructional content, particularly his detailed teachings on the Body Lock Pass. Known for clear and effective communication, Giles makes complex techniques accessible to practitioners of all levels. His instruction frequently integrates anatomical and biomechanical explanations, reflecting his academic background and commitment to evidence-based coaching.

Beyond the mats, Giles earned a PhD in Physiotherapy in 2016, specializing in patellofemoral pain. His academic career includes peer-reviewed research publications on knee injuries, rehabilitation protocols, and Brazilian Jiu-Jitsu-specific training methods. Giles operates a private physiotherapy clinic in Melbourne alongside his wife, fellow BJJ black belt Livia Giles. His scientific expertise uniquely informs his coaching, optimizing training methods, injury prevention strategies, and overall athlete performance.

Giles is renowned for his precise leg lock entries and mastery of heel hook submissions, techniques he has successfully employed against larger opponents. His strategic approach emphasizes leveraging technique, positioning, and systematic troubleshooting to overcome strength and size disadvantages. Giles' methodical and conceptual understanding of positions has become a hallmark of both his competitive and instructional styles.

As a leading figure in Australian grappling, Giles has significantly elevated Australia's global reputation in Brazilian Jiu-Jitsu through his competitive achievements and coaching successes. He has developed numerous homegrown talents who have achieved international recognition, solidifying his role as Australia's unofficial ambassador in the global grappling community.

Lachlan Giles exemplifies exceptional work ethic by successfully balancing multiple demanding roles: clinician, researcher, elite competitor, and coach. Known for his relentless curiosity, Giles is often observed on the mats recording new ideas and techniques to test and refine. Although he continues to compete occasionally, particularly in local Australian events or Masters divisions, Giles has expressed that his true passion lies in solving jiu-jitsu puzzles and helping others improve. This multifaceted approach has earned him the affectionate nickname "the professor" among peers, highlighting his intellectual and analytical contributions to the sport.