Here’s the format of Swim Smooth‘s Paul Newsome’s weekly regime while training for the 46km Manhattan Island Marathon Swim – roughly 50k per week:
• Monday = 3km easy technique swim (pool)
• Tuesday = 10km challenging aerobic swim (80% pool and 20% open water), e.g. 10x 800m + 2km open water swim
• Wednesday = 3km easy technique swim (pool)
• Thursday = 10km challenging open water swim at 1:18 to 1:22 pace per 100m (completed now 25 weeks in a row)
• Friday = 3km easy technique swim (pool)
• Saturday = 4km to 8km challenging aerobic swim, e.g. 2x (1600m, 800m, 2 x 400m, 4 x 200m) working down from 1:25 to 1:17 per 100m
• Sunday = 14km to 20km long race simulation swim with my best being a 4h35m 20km swim (1:22/100m) on the 19th May
Much respect for whoever can maintain such an ordeal week-in week-out for 6 months or so !