CSS 3 x 400 m with Fast 50s
A 2900 m threshold session with three 400 m repeats just slower than CSS and eight 50s slightly faster than CSS to finish the main set.
- Duration
- 1 h 02 minestimated
- Distance
- 2,900 m
- Effort
- 79
- Level
- Intermediate
- Focus zone
- Threshold
Your values
Targets relative to your threshold values. Enter your values to see absolute numbers.
100% is your threshold pace. Higher values are faster, lower values are slower.
| # | Step | Length | Target |
|---|---|---|---|
| 1 | Warm-upEndurance Easy freestyle | 400 m | 85-92% CSS pace |
| 2 | Rest | 20 s | |
| 4 ×Repeat these steps | |||
| 3.1 | Warm-upRecovery Drill of choice | 50 m | 75-85% CSS pace |
| 3.2 | Rest | 15 s | |
| 4 ×Repeat these steps | |||
| 4.1 | Warm-upTempo Build to CSS pace | 50 m | 92-96% CSS pace |
| 4.2 | Rest | 15 s | |
| 5 | Rest | 45 s | |
| 3 ×Repeat these steps | |||
| 6.1 | IntervalThreshold Freestyle, CSS plus 1 to 2 s per 100 m | 400 m | 97-100% CSS pace |
| 6.2 | Rest | 30 s | |
| 7 | RecoveryRecovery Easy freestyle | 200 m | 75-85% CSS pace |
| 8 ×Repeat these steps | |||
| 8.1 | IntervalThreshold Freestyle, CSS minus 2 s per 100 m | 50 m | 101-104% CSS pace |
| 8.2 | Rest | 15 s | |
| 9 | Cool-downRecovery Easy choice of stroke | 300 m | 75-85% CSS pace |
About this workout
Four hundreds are the longest standard repeat in CSS training. They take five to eight minutes each for most swimmers, so pacing and concentration matter as much as fitness. Swim them one to two seconds per 100 m slower than your CSS with 30 seconds rest. That pace looks easy on paper and feels hard by the third repeat.
After an easy 200 the set changes gear. Eight 50s at about two seconds per 100 m faster than CSS, on 15 seconds rest, remind the body what a quicker turnover feels like when you are already tired, which helps in the last part of a race.
This session suits intermediate swimmers and triathletes preparing for a standard-distance or longer swim. Start with 2 x 400 if you are new to threshold work, and build to 4 x 400 over a few weeks.
Tips
- Check your 100 m splits on the first 400 and adjust before the second.
- Keep the 50s fast but long, do not let the stroke shorten.
- Take a drink during the easy 200 if you need it.
Good forPoolOpen waterStandard-distance triathlonHalf-distance triathlon
Season phaseBuildPeak