Just to give you an idea, here is the 6 months training prior to Arch to Arc. I had very rough weekly schedule where I would swim 4 mornings a week and 2 evenings a week as well as either running or biking to the pool/work. Then I would something long at the weekend both days if I could. I never once completed all sessions in a week but there was plenty in there. Swim times are recorded as actual moving time, not pool time which was a lot longer
Week 1 13h31m - S 3h13m, B 4h9m, R 6h9m - includes marathon
Week 2 18h56m - S 8h6m, B 3h12m, R 7h37m - includes 10k swim and marathon
Week 3 11h23m - S 2h41m, B 0h0m, R 8h41m
Week 4 9h37m - S 4h8m, B 3h1m, R 2h27m
Week 5 10h50m - S 3h19m, B 3h30m, R 4h1m
Week 6 15h55m - S 8h29m, B 5h52m, R 1h33m - includes 10k swim
Week 7 14h38m - S 5h45m, B 4h31m, R 5h45m
Week 8 18h24m - S 9h2m, B 0h32m, R 8h46m - includes 11k swim and marathon
Week 9 16h20m - S 4h4m, B 8h38m, R 3h37m - includes 100 mile bike
Week 10 15h19m - S 7h32m, B 1h29m, R 6h16m
Week 11 18h18m - S 6h27m, B 0h25m, R 11h15m - includes 8hr (30 mile) speed march in a blizzard
Week 12 7h6m - S 4h30m, B 2h35m, R 0h0m - moved house
Week 13 26h6m - S 4h17m, B 17h42m,R 4h7m - includes 100 mile bike and marathon
Week 14 13h33m - S 4h4m, B 4h9m, R 5h19m
Week 15 13h58m - S 5h18m, B 3h52m, R 4h46m
Week 16 15h24m - S 7h15m, B 5h58m, R 2h10m
Week 17 26h28m - S 14h13m,B 2h34m, R 9h40m - includes 40 mile run and 24 mile swim (1 mile each hour)
Week 18 12h6m - S 5h58m, B 4h44m, R 1h24m
Week 19 11h54m - S 4h3m, B 6h7m, R 1h43m
Week 20 16h10m - S 9h53m, B 3h17m, R 2h59m - includes 6hr (13 mile) channel swim qualification
Week 21 14h55m - S 5h6m, B 2h40m, R 7h8m
Week 22 17h55m - S 4h36m, B 11h44m,R 1h35m - includes 162 mile bike
Week 23 23h39m - S 7h12m, B 3h45m, R 12h42m - includes 52 mile run
Week 24 13h26m - S 4h28m, B 6h39m, R 2h18m
Week 25 12h40m - S 7h26m, B 1h28m, R 3h45m
Week 26 6h6m - S 2h56m, B 2h2m, R 1h8m - 3 days only. A2A started on Thursday lunchtime