Swimming: The Complete Training Guide

Strokes, drills, pacing, open water, and AI coaching for swimmers and triathletes.

Swimming fundamentals

Swimming is the most technique-dependent of the triathlon disciplines. Unlike running and cycling where fitness improvements translate directly to speed, a swimmer with poor technique can have excellent aerobic fitness but still swim slowly.

The front crawl (freestyle) is the fastest and most efficient stroke for triathlon. Mastering bilateral breathing, horizontal body position, high elbow catch, and efficient kick are the four pillars of fast, sustainable freestyle swimming.

Key swim drills for triathletes

Catch-up drill

Develops timing and full extension — each arm waits at full reach before the other completes the pull.

Improves stroke timing and front quadrant swimming

Fingertip drag

Drag fingertips along the water surface during recovery to enforce high elbow position.

Fixes dropped elbow on recovery phase

Kick sets with fins

Isolated kick sets develop ankle flexibility and kick efficiency without total exhaustion.

Strengthens kick and improves body position

Single-arm drill

Swim with one arm while the other stays at side or extended. Forces focus on catch and pull mechanics.

Reveals asymmetry and improves catch technique

Bilateral breathing

Alternate breathing sides every 3 strokes to develop even stroke balance.

Prevents stroke asymmetry, critical for open water sighting

Sighting practice

Practice lifting eyes forward briefly without interrupting stroke rhythm — essential for open water navigation.

Open water navigation efficiency

Pace zones and pacing strategy

Swimming pacing is measured per 100m (or 100 yards). Unlike running where pace is intuitive, swimmers need to train across a range of intensities to develop both aerobic fitness and speed.

IntensityEffortBest forTypical % of training
Easy/recoveryVery comfortableWarm-up, cool-down, recovery30%
Aerobic baseConversationalBase building, long sets40%
ThresholdControlled hardCSS (Critical Swim Speed) training20%
VO2 Max / SpeedHard to maxShort repeats, speed development10%

Pool vs open water swimming

Pool training advantages

  • • Precise pace measurement (100m splits)
  • • Consistent conditions for structured work
  • • Easy to track intervals and rest periods
  • • Year-round accessibility
  • • Best for technique work and drilling

Open water advantages

  • • Race-specific conditions (chop, current, wetsuit)
  • • Navigation and sighting practice
  • • Mass start simulation
  • • Mental comfort for race day
  • • Drafting technique development

Tracking swimming with Flip My Performance

Syncs pool and open water swims from Garmin, Apple Watch, Polar, and Strava
Tracks pace per 100m trends over time
SWOLF score tracking for efficiency monitoring
Pool vs open water volume breakdown
Swimming contributes to overall multisport training load
For triathletes: swim + bike + run combined CTL view

Swimming FAQ

Track your swimming with AI

Connect Garmin or Apple Watch and get AI insights on your swim training.

Start Free →