CSS Speed Pyramid: 5×200m Descending Pool Session

Session Overview

This 45-minute CSS speed pyramid targets your Critical Swim Speed threshold with five descending 200m repeats, helping you hold your fastest sustainable pace while building lactate tolerance. It’s ideal for intermediate swimmers preparing for sprint or Olympic-distance racing.

What You’ll Need

  • 25m or 50m pool
  • Pace clock or swim watch
  • Pull buoy (optional warm-up aid)
  • Goggles and swim cap

Warm-Up (10 minutes)

Swim 400m easy as 200m freestyle, 100m backstroke, 100m freestyle with a focus on long stroke and relaxed breathing. Add 4 x 25m build efforts, starting at 60% effort and finishing at 80%. Rest 15 seconds between each build.

Main Set

The pyramid drops target pace by 2–3 seconds per 100m with each rep, finishing with your fastest effort. Each rep is a full 200m. Take 40 seconds rest between repeats to allow partial recovery while maintaining quality. Total main set distance: 1,000m.

  • Rep 1: 200m at CSS pace + 6 seconds per 100m (controlled, settling in)
  • Rep 2: 200m at CSS pace + 4 seconds per 100m (building effort)
  • Rep 3: 200m at CSS pace + 2 seconds per 100m (working hard)
  • Rep 4: 200m at CSS pace (true threshold effort)
  • Rep 5: 200m at CSS pace − 2 seconds per 100m (maximum sustainable sprint)

Cool-Down (5 minutes)

Swim 200m easy, alternating 50m backstroke with 50m gentle freestyle. Focus on slow, controlled breathing and letting your heart rate drop. Finish with light shoulder stretches on the pool wall.

Coaching Notes

  • If you don’t know your CSS pace, swim a 400m TT and a 200m TT on separate days and use an online CSS calculator to find your target per 100m
  • Avoid going out too hard on Rep 1 — the descending structure only works if you have something left for Rep 5
  • Focus on stroke rate and catch depth as fatigue accumulates, not just kicking harder
  • To make it easier, extend rest to 60 seconds; to make it harder, cut rest to 25 seconds and add a 6th rep at CSS − 3 seconds
  • Target RPE 7–8 on Reps 3–4, RPE 9 on Rep 5

Training at your own risk. The information provided is for general guidance only and is not a substitute for professional medical advice. Please consult a doctor before starting any new exercise programme, especially if you have any pre-existing health conditions.