Open Water 5x300m Race Pace Swim Session

Session Overview

This open water interval session uses 5 x 300m efforts at race pace to build your ability to distribute effort evenly across the swim leg. It is ideal for intermediate triathletes preparing for sprint or Olympic distance races — the interval structure trains pacing discipline and sustained race-level intensity in real open water conditions.

What You’ll Need

• Open water venue (lake, reservoir, or sheltered sea swim area)
• Wetsuit if water temperature is below 22°C
• Tow float or safety buoy (mandatory at most open water venues)
• Swim watch or GPS with open water mode
• Swim partner or lifeguard supervision at the venue

Warm-Up (10 minutes)

Begin with 10 minutes of easy freestyle at conversational effort — RPE 3–4 out of 10. Focus on long strokes, relaxed bilateral breathing, and getting fully comfortable in the water before the main set. Include 4–6 brief sighting efforts to establish your navigation pattern.

Main Set

Complete 5 x 300m at race pace (RPE 7–8 out of 10) with 60 seconds of active rest between each rep. During rest, tread water or float — do not swim back toward a buoy, as the movement disrupts recovery. Aim to hold consistent pace across all five reps. If you fade significantly on reps 4–5, you started too hard.

• Rep 1: Controlled — establish your target pace at RPE 7
• Reps 2–3: Hold pace, practise sighting every 6–8 strokes
• Rep 4: Push slightly — RPE 7.5, maintain stroke rate throughout
• Rep 5: Race effort — RPE 8, strong finish with a firm kick in the last 50m
• Rest: 60 seconds between every rep

Cool-Down (10 minutes)

Swim 10 minutes of easy backstroke or relaxed freestyle at RPE 2–3. Focus on recovering your breathing and stretching through the shoulders and hips. Exit the water slowly and spend 5 minutes stretching lats, chest, and hip flexors on the bank.

Coaching Notes

• Sight every 6–8 strokes in open water — increase frequency near buoys or in choppy conditions
• Even pacing across 300m is consistently faster than sprinting the first 100m and fading
• Beginners: reduce to 4 x 200m with 90 seconds rest until open water confidence is established
• Advanced: reduce rest to 45 seconds and add a sixth rep for additional lactate tolerance work