The IRONMAN swim glossary. An asterisk marks a term specific to IRONMAN-branded events.
SWIM
New to the swim, or just want the lingo straight? This glossary explains the swimming terms you will hear in training and on race day, from open-water starts to strokes, drills, and gear. Skim it, or jump to what you need.
Race-Day and Open-Water Terms
Rolling startIRONMANAthletes enter the water a few at a time, seeded by expected swim pace. This is the most common IRONMAN start format today.
Mass startIRONMANThe whole field starts the swim together, often 10 to 15 minutes after the pros. Used at some championship events.
Beach startStarting the swim from dry land and running into the water.
Floating startAlso called a water start. Starting from a treading-water position in deep water.
SightingLifting your head to see where you are going and spot buoys, other swimmers, or the shore.
BuoyA floating marker that shows the course layout, distance, and turns.
DraftingSwimming just behind or beside another swimmer to make swimming easier.
Open waterSwimming outdoors in a lake, river, or ocean.
Wetsuit legalA race where the water is cool enough to allow a wetsuit, usually at or below 76.1 degrees Fahrenheit (24.5 Celsius) for age-groupers.
SwimSmartIRONMANAn IRONMAN safety and preparation program, launched in 2013, that brings innovation to IRONMAN swims.
Strokes and Technique
FreestyleThe front-crawl stroke used by almost every triathlete.
BackstrokeSwum on your back. Useful for warm-ups and recovery.
BreaststrokeA slower, frog-kick stroke. Handy for sighting or catching your breath.
ButterflyA powerful two-arm stroke, rarely used in triathlon.
Bilateral breathingBreathing on alternating sides, which keeps your stroke balanced.
The catchThe moment your hand and forearm grip the water at the front of the stroke.
Flip turnAn underwater somersault at the wall to change direction in a pool.
Dolphin kickAn up-and-down kick from the hips with both legs together.
Training and Pool Terms
BaseAlso base pace. The pace you can hold for interval sets. Also the lane you pick in a masters class.
Main setThe bulk of a coached workout, often 2,000 to 4,000 yards or meters.
Warm-upEasy swimming at the start of a session to prepare the body.
Cool-downEasy swimming at the end to flush the arms and lower the heart rate.
DrillsSpecific exercises that improve technique and feel for the water.
Negative splitSwimming the second half of a set or race faster than the first.
Circle swimSwimming in a continuous loop within a shared lane, keeping to the right.
LaneA sectioned area of the pool for lap swimming.
Lane linesThe floating markers that separate lanes.
LengthOne end of the pool to the other.
DeckThe hard surface around the pool.
FlagsSmall pennants hung over the pool to signal the wall is near, useful for backstroke.
MastersA coached swim group or club for adult swimmers.
Gear
GogglesEyewear for clear vision in the water. Pack a clear and a tinted pair for race day.
KickboardA foam board held out front for kicking drills.
Pull buoyA foam float held between the legs to isolate and work the upper body.
PaddlesHand plates that add resistance to build upper-body strength.
FinsFlippers that add propulsion and change the focus of the kick in drills.
Frequently Asked Questions
What is the IRONMAN swim distance?
A full IRONMAN swim is 2.4 miles (3.8 km) and an IRONMAN 70.3 swim is 1.2 miles (1.9 km). Both are open-water swims and the first leg of the race.
What is sighting in open-water swimming?
Sighting is lifting your head to look forward while you swim, so you can spot buoys, other swimmers, and the shore and stay on course without a pool wall to guide you.
What is a rolling start in an IRONMAN?
In a rolling start, athletes enter the water a few at a time, seeded by their expected swim pace, rather than all at once. It is the most common IRONMAN start format today.
What does wetsuit legal mean?
A race is wetsuit legal when the water is cool enough to allow a wetsuit, usually at or below 76.1 degrees Fahrenheit (24.5 Celsius) for age-group athletes.
What is bilateral breathing?
Bilateral breathing means breathing on alternating sides as you swim freestyle. It keeps your stroke balanced and helps you sight on both sides in open water.
