Jack Duncan spent five years in The Royal Marines, including a spell as a sniper, before becoming a Personal Trainer in the Cheltenham area of The UK. Jack uses a nutrition-lead approach with clients. He also has an exercise clothing brand - Front Line Fitwear - which donates a percentage of its profits to help ex military personnel who are suffering from mental health issues: http://www.frontlinefitwear.co.uk @frontlinefitwear on Instagram.