Swim training that understands the pool
Training load from your critical swim speed, your sets analysed from the laps of your watch, and an AI coach that fits your swims into the rest of your week.
Swimming is where most training apps give up: no power, unreliable heart rate and pace measured per 100 metres. Strilab uses the right reference for the water, your critical swim speed (CSS), to work out how hard every session was, in the pool or in open water.
Your swims feed the same fitness and fatigue model as everything else you do, so the AI coach knows how a hard set on Tuesday affects the rest of your week.
What Strilab does for you
Load based on your CSS
Each swim is scored against your critical swim speed. Because effort in the water rises steeply with speed, Strilab uses a cubic intensity factor (hours × IF³ × 100).
Pool and open water
Pool swims and open water swims are imported from Garmin or Strava with distance, duration, pace per 100 m and stroke rate.
Your sets, analysed
The laps your watch records are used to find the reps of your session and tell you how even your pace was across the set.
One model for all your training
Swims add to the same fitness, fatigue and form as your runs and rides, so your load reflects everything you do.
A coach that plans your swims
Ask the AI coach how many swims fit this week or how to prepare your next race, and it answers with your calendar and your recent sessions.
Stats that show progress
Follow your weekly swim volume and how your CSS evolves over months on the stats page.
Goals you can train for
Pick a swim event as your goal or train swimming as part of a triathlon.
- 1,500 m
- 3,800 m
- Open water race
- Triathlon swim
- Your own distance
The numbers behind your training
- CSS
- Critical swim speed, edited in min/100 m: your threshold in the water.
- Pace per 100 m
- The way swimmers think about speed, in every session and set.
- Stroke rate
- Strokes per minute, when your watch records them.
- Training stress
- How much each swim adds to your load, comparable with your other sports.
Frequently asked questions
What is CSS and how do I set it?
Critical swim speed is the pace you can hold for a long, hard effort, roughly your threshold in the water. A common test is a 400 m and a 200 m time trial. Enter it in your athlete settings as min/100 m.
Does Strilab support open water swimming?
Yes. Open water swims are imported with their GPS track, distance and duration, and count towards your training load like pool sessions.
Why is swim load calculated differently?
Resistance in water grows much faster with speed than on land, so Strilab uses a cubic intensity factor for swimming (hours × IF³ × 100) instead of the squared one used for running and cycling.
Which watches work for swimming?
Any watch that uploads swims to Garmin Connect or Strava. Laps recorded in the pool make the set analysis more accurate.
Learn more on the blog
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Understanding Training Periodization for Endurance Athletes
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Recovery and Tapering: The Science of Rest
Discover why recovery and tapering are essential for endurance performance. Learn evidence-based strategies to rest smarter and race faster.
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Understanding CTL, ATL, and TSB: Your Fitness Performance Model
Learn how Chronic Training Load, Acute Training Load, and Training Stress Balance help you monitor fitness, fatigue, and form for peak performance.
Read article →Other sports
Make every length count
Connect your watch, set your CSS and see your swims in the same picture as the rest of your training.
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