Swimming
Left-Arm Butterfly Drill
The Left-Arm Butterfly Drill uses one arm for butterfly strokes while the other stays extended forward. It trains upper-body pulling and the timing between your arm stroke, body wave, and dolphin kicks.
- Intermediate
- Moderate injury risk
- Rest 30 sec
How to do it
- Push off the wall face down with both arms extended forward.
- Make a small dolphin kick with your legs together.
- Bend your left elbow to angle your hand and forearm toward the pool bottom.
- Pull your left hand back toward your hip.
- Make the second dolphin kick as the pull finishes.
- Sweep your left arm forward above the water.
- Enter the water with your left hand in line with your shoulder.
- Reach your left arm forward to finish the stroke.
Form cues
- Keep your right arm still out front.
- Lead the wave with your chest.
- Exhale into the water.
- Breathe left as your arm recovers.
Common mistakes
- Crossing the centerlineKeep your left hand on its own side throughout the pull rather than sweeping beneath your right shoulder.
- Kicking mainly from the kneesLet the kick travel from your hips through relaxed knees to your feet instead of bicycling your lower legs.
- Lifting your head to breatheTurn only enough for your mouth to clear the surface so your hips do not sink.
Safety
Forcing the arm recovery or continuing when tired can strain your shoulder. Losing breathing control in the water creates a drowning risk, even during short drill lengths.
- Practice in a lifeguarded pool only if you can already swim a length comfortably.
- Check lane traffic before pushing off, leaving enough space for your wide arm recovery.
- End the interval at the wall before fatigue disrupts your stroke; stop immediately for pain or breathing distress.
If you have shoulder or neck pain, limited overhead reach, or difficulty coordinating dolphin kicks, choose a simpler drill or seek guidance before attempting this version.
Muscles worked
Primary muscles
Secondary muscles
Equipment
- Pool Lane Line (optional)
Sets and reps
- Sets
- 4–6
- Target
- 25 meters
- Rest
- 30 sec
Use an easy technique pace and practice an equal distance with the right-arm version.