Dr Nessan Costello is a Senior Lecturer in Sport and Exercise Nutrition at Leeds Beckett University and a practising sport nutrition consultant with over a decade of experience in elite sport. He has worked with Premier League footballers, Grammy-winning performers, and high-performing executives. His consultancy roles include Chelsea FC, Leeds United, and Newcastle United – most notably supporting Chelsea’s UEFA Conference League and Club World Cup wins in 2025, and Leeds United’s return to the English Premier League in 2019 after a 16-year absence. Alongside his applied work, Nessan co-leads a practitioner-focused PhD programme at Leeds Beckett, supervising research into energy expenditure, hydration, body composition, and behaviour change in high-performance environments. He has authored over 25 peer-reviewed publications and secured more than £750K in research funding. Through his dual focus on elite practice and academic development, Nessan bridges the gap between science and real-world delivery – driving innovation, research, and professional standards in sport and exercise nutrition.
