10km Marathon Swim Training Plan Welcome to your 10km Marathon Swim Plan! This plan is ideal for swimmers who want to take on the challenge of a 10km Marathon swim. This plan has a variety of sessions - Endurance, Speed, Power and Technique. Easy to follow sessions with drill videos and structured session you can load onto your Garmin etc. It's great for intermediate swimmers for the full 20 weeks but if you are an experienced/advanced swimmer you can jump in further down the plan. To ...