1500m is 60 lengths of a 25m pool, a sensible size for a regular session and the swim distance in an Olympic triathlon. The first three sets below add up to exactly 1500m. The last two are longer and are about getting faster over 1500m.
4 × 100 free @ 2:00 means swim four 100s, leaving every two minutes; whatever time is left is your rest. 20s rest means rest 20 seconds after each one. Send-offs are set for the pace on each card, so add five seconds if they feel tight. All sets are in metres for a 25m pool. Load this set opens it in the builder, where you can change anything, print it or send it to your Garmin.
For: Regular lap swimmers who can swim 400m comfortably.
If 2:55 is tight, go on 3:05. Same for every send-off on this page.
For: Fitter swimmers who want a hard half hour.
Note your time on the first 100. The aim is to hold it, not beat it.
For: Swimmers working towards a non-stop 1500m.
Each week, try cutting 5 seconds off the 200 send-off.
For: Anyone who wants a feel for their 1500m without doing a time trial.
Add up the five swim times and you have a fair guess at your 1500m.
For: Triathletes targeting an Olympic-distance swim.
As it gets easier, cut the send-off by 5 seconds rather than adding more 300s.
At 2:00 per 100m it takes 30 minutes non-stop. At 1:40 per 100m it's 25 minutes, and at 2:30 per 100m it's about 37 minutes. Add your rest on top for a session with breaks.
60 lengths of a 25m pool, or 30 lengths of a 50m pool.
Mix steady longer reps for your base with some threshold work like 100s on a tight send-off. The broken 1500m ladder on this page is a good way to check progress every few weeks.
All 28 sets are on the workouts page, grouped by goal.