Saturday Swim Session: 100s Into Fast 50s

The 100s Into Fast 50s workout develops consistent freestyle swimming before challenging you to increase your speed over shorter repetitions. Start with controlled, repeatable 100m efforts, then change gears for faster 50s while maintaining good technique and consistent pacing. Choose from three workout options of 1,700m, 2,400m or 3,200m.

How well can you change gears in the pool without losing your technique?

This week’s Saturday Swim Session combines consistent 100m freestyle repetitions with shorter, faster 50m efforts. The idea is simple: establish quality swimming over the 100s, then use the shorter distance and additional recovery to increase your speed.

Establish Your Rhythm Before Increasing the Speed

The workout begins with a set of 100m repetitions with a 30-second Rest Interval (RI).

Rather than attacking the opening rep, aim to produce strong, repeatable swimming. Your pace should be sustainable enough that your final 100m remains comparable with your first.

Once those are complete, you’ll move into the second main set of 50m repetitions.

This time you’ll have a 45-second RI, giving you more recovery and an opportunity to increase your speed.

The 50s should be as fast as possible while continuing to swim with good technique and staying consistent with pace (the last rep should be as fast as the first rep).

Choose Your Workout

Option A – 1,700m
300m WU; 6 × 100m (30sec RI); 12 × 50m (45sec RI); 200m CD.

Option B – 2,400m
600m WU; 8 × 100m (30sec RI); 16 × 50m (45sec RI); 200m CD.

Option C – 3,200m
1,000m WU; 10 × 100m (30sec RI); 20 × 50m (45sec RI); 200m CD.

The Challenge Is Repeatable Speed

Don’t make the mistake of turning the first few 50s into an all-out sprint and then watching your pace gradually disappear.

You have 12, 16 or 20 × 50m to complete.

Use the recovery, swim fast and concentrate on maintaining a strong catch, good body position and controlled technique throughout the set.

Your final few 50s are particularly important. If your last repetition can compete with your first, you’ve probably judged the set well.

The goal isn’t simply to swim one fast 50m.

It’s to produce repeatable speed after already completing a solid block of 100m swimming.

👉 Read the complete workout and my coaching advice:
Saturday Swim Session: 100s Into Fast 50s