SPL: The Hidden Metric That Transforms Your Swimming

Do you know the hidden metric that transforms your swimming? Many swimmers obsess over speed and distance — but they're missing a crucial indicator.

SPL (Strokes Per Length) measures how many strokes you take to cover 25 meters. It's a direct indicator of your swimming efficiency and technique quality.

What is SPL Exactly?

SPL stands for Strokes Per Length. To calculate yours:

1. Push off the wall and start counting after your breakout
2. Count every arm entry (one stroke = one arm entering the water)
3. Stop counting when you touch the opposite wall
4. That number is your SPL

For front crawl, you count each hand entry. For breaststroke, each arm pull cycle counts as one.

What's a Good SPL?

It depends on your height, because taller swimmers naturally cover more distance per stroke:

Note: These are targets for efficient, relaxed swimming. During sprints, SPL naturally increases as you trade efficiency for speed.

Why Does SPL Matter?

Lower SPL = longer strokes = better technique = less energy wasted.

Here's what high SPL often indicates:

• Short, choppy strokes — not fully extending
• Poor catch — slipping through the water
• Early hand exit — not finishing the pull
• Excessive drag — body position issues

And what optimized SPL indicates:

• Full extension — maximizing distance per stroke
• Strong catch — grabbing the water effectively
• Complete pull — finishing each stroke
• Streamlined position — minimal resistance

The SPL + Tempo Equation

The magic happens when you combine SPL with stroke rate (tempo):

Pace = (SPL × Tempo) + Glide Time

This is the Total Immersion formula. It means you can swim faster by:

1. Lowering SPL (more distance per stroke) at the same tempo
2. Increasing tempo while maintaining SPL
3. Finding your optimal combination of both

Elite swimmers often train both variables separately, then combine them for racing.

How to Improve Your SPL

Technique Drills

• Catch-up drill — forces full extension
• Fingertip drag — promotes high elbow recovery
• Fist swimming — improves feel for the water

Focus Points

• Reach forward before catching
• Rotate your hips to extend reach
• Finish each stroke past your hip
• Streamline off every wall

Track Progress

Keep a simple log:

• Date
• SPL at easy pace
• SPL at moderate pace
• Notes on how it felt

Over weeks and months, you should see your efficient SPL decrease.

Quick Tip for Your Next Swim

Count your strokes on your next swim session. Do 4×50m at easy pace and record your SPL for each length.

Then ask yourself:

• Is it consistent across all lengths?
• Does it increase when you get tired?
• Can you lower it by 1 stroke while maintaining speed?

Track it over time. As your technique improves, you'll see that number drop.

What's your current SPL? Many swimmers are surprised when they first count — it's often higher than expected. The good news: there's almost always room to improve.