Week 6: Efficiency and Open Water
Week 6 of this advanced swim workout holds volume at 3,200m but pulls intensity back from week 5 and turns the focus to efficiency and open water transfer. Twenty hundreds, four four-hundred IMs, and eight hundred metre sighting swims, all in Salty Johnson recycled ocean plastic swimwear that handles the pool and the point-to-point equally well.
Week 6 at a glance: 3 sessions · 3,200m each · 25m pool · kickboard and pull buoy · about 90 minutes per swim.
Session 1: Sprint (3,200m, ~90 min)
Introduction: The classic 20x100m, the most honest set in swimming.
- Warm-up: 400m freestyle, 200m choice.
- Main Set: 20x100m freestyle at threshold, 20s rest; 4x50m sprint, 30s rest.
- Cool-down: 400m easy.
Technique: Hold stroke count within one stroke per length across all twenty.
Tips: Pick a target you can hold for rep 20, not rep 1, then hold it.
Motivation: Twenty hundreds tells you exactly where your fitness is, no negotiating!
Session 2: Mixed Strokes/IM (3,200m, ~90 min)
Introduction: Four 400m IMs, the full distance, at controlled rather than racing effort.
- Warm-up: 600m (200m freestyle/200m IM order drill/200m kick).
- Main Set: 4x400m IM, 45s rest; 12x50m rotating butterfly, backstroke, breaststroke, freestyle, 20s rest.
- Cool-down: 400m easy.
Technique: Negative split each 400m IM, the breaststroke and freestyle half should be the stronger one.
Tips: If butterfly technique breaks before 75m, swim the first 50m and kick the last 50m.
Motivation: Sixteen hundred metres of IM, and the 50s afterwards are the easy part!
Session 3: Endurance (3,200m, ~90 min)
Introduction: Two 800m swims, the second built as a full open water simulation.
- Warm-up: 400m freestyle, 200m kick.
- Main Set: 2x800m freestyle, 60s rest. Swim the second with two sighting lifts per length and no push-off streamline; 3x200m freestyle, 30s rest.
- Cool-down: 400m easy.
Technique: Keep the sighting lift low, a high head drops the hips and costs more than the look is worth.
Tips: Compare your two 800m times, the gap is roughly what open water will cost you on race day.
Motivation: Rehearse the race, do not just train for it!
Salty Johnson Spotlight: Ninety minute sessions three times a week is where fabric quality stops being a marketing line and starts being a budget item. Our women's one-pieces and men's board shorts are made from recycled ocean plastic with UPF 50+, designed to outlast a full ocean swim season. Grab yours at www.saltyjohnson.com.au/collections/sustainable-womens-one-piece-swimsuits for her or www.saltyjohnson.com.au/collections/board-shorts for him.
Made from ocean plastic, built for ocean swims, which is either poetic or just good engineering!
Advanced swim workout questions, answered
What is the point of a 20x100m set?
It is a threshold benchmark. Twenty repeats on short rest is long enough that you cannot fake it with sprint fitness, and the spread between your first and last rep is a direct readout of your aerobic base.
How do you simulate open water in a 25m pool?
Sight twice per length, skip the push-off streamline so you lose the free metres a wall gives you, swim long unbroken sets, and where possible share a lane closely to mimic pack swimming and broken water.
Should I swim a 400m IM if I am a distance freestyler?
Yes, at controlled effort. It builds kick, body position and shoulder balance, and it is the single most efficient way to find out which part of your technique fails first under fatigue.
How much weekly volume do I need for a 5km ocean swim?
Around 9 to 12km a week, with at least one continuous swim of 2.5km or more in the final four weeks. This program's 9.6km week 6 sits right in that band.
Keep the series going
- Previous: Advanced Week 5, Speed Endurance (3,100m)
- Next: Advanced Week 7, Peak Volume (3,400m)
- Scaling back? Intermediate Week 6 (1,400m)
- All free plans: Salty Johnson swim workouts and Salty Sundays in Bondi