Long Course Swim: Building Endurance

Session Overview

This challenging 60-minute pool session builds the sustained endurance required for 1900m to 3800m open water swims. Using progressive rest structures and long continuous efforts, you will develop aerobic swimming capacity and mental resilience for IRONMAN and 70.3 swim legs. Designed for advanced triathletes in peak or race-prep training phases.

What You’ll Need

• Pool access (25m or 50m)
• Pull buoy
• Paddles (optional, for final set)
• Swim watch or poolside clock for interval timing
• Water bottle at pool edge

Warm-Up (10 minutes)

400m easy: alternate 100m freestyle and 100m backstroke x2. Focus on long, relaxed strokes. Finish with 4 x 25m high elbow catch drills at easy pace.

Main Set

Total main set distance: approximately 2000m. Keep your technique consistent under fatigue.

• 3 x 500m at 70% effort, 30 seconds rest between each (1500m total) — aim for even splits
• 200m easy backstroke or mixed stroke recovery
• 4 x 100m descending (each 100m faster than the previous), 20 seconds rest between each
• 100m easy cool-in before the cool-down

Cool-Down (5 minutes)

200m very easy backstroke and breaststroke mix. Focus on relaxed breathing and loosening the shoulders and upper back.

Coaching Notes

• For the 500m sets, resist going out too fast on set 1 — aim for even 100m splits throughout all three reps
• Use the pull buoy for set 3 if shoulder fatigue sets in, isolating upper body endurance
• Scaling down: replace 500m sets with 400m sets and take 45 seconds rest
• RPE for 500m sets: 6-7. Final descending 100m: 8-9