Swim technique changes with speed and fatigue, so changes practised only slowly in drills may not carry over to race pace; practise them in full stroke at speed and when tired, with external cues
Interpretation
Triathletes' main swim deficit is efficiency rather than power (Toussaint 1990: 6 swimmers vs 5 triathletes, 1.23 vs 0.92 m per stroke, propelling efficiency 61% vs 44%). Coordination shifts from catch-up to near-continuous propulsion between 80% and 98% of maximal speed in 19 elite triathletes and 15 elite swimmers (Millet 2002), and fatigue shortens and slows the stroke in 17 competitive swimmers (Alberty 2005). Motor-learning evidence (Schmidt and Bjork 1992 review; Chua 2021 meta-analysis, 73 and 40 studies) shows practice performance is a poor guide to retention and favours external cues, supported by two short swimming studies (Freudenheim 2010; Stoate and Wulf 2011). Graded limited: no trial of a drill or technique block in adult triathletes, small or unreported samples, and most retention evidence comes from non-swimming tasks.
Practical implication
Pick one or two changes, use one external cue for each, link drills to full-stroke swimming, then progress the change to threshold and race pace and practise it at the end of hard sets; recheck with video every four to six weeks. This is inference from pool-swimmer and general motor-learning research, not a tested triathlon programme.
Sources
8 sources, independently verified.
MSSE 22(3):409–415. At an equal power input (1000 W), groups did not differ in gross efficiency, stroke frequency or work per stroke, but competitive swimmers covered 1.23 vs 0.92 m per stroke and swam 1.17 vs 0.95 m/s; propelling efficiency 61 ± 6% vs 44 ± 3%. The triathletes' deficit was efficiency, not capacity to do work; the author recommends triathletes prioritise technique. Very small, older sample.
Filmed at six speeds from 80% to 100% of maximal velocity. Index of coordination rose in both groups from catch-up (about -8.8% triathletes, -8.6% swimmers) at 80% to about 2.6% and 0.3% at 98%, i.e. coordination changes with speed. Triathletes' stroke length at maximal speed 1.70 m vs 2.15 m for swimmers. Cross-sectional; no training intervention.
Two maximal 25 m efforts before and after an all-out 200 m. With fatigue, stroke length and stroke rate fell (p<0.05), the propulsive phase lengthened and arm coordination changed; intracyclic velocity variation did not change significantly. Abstract gives directions, not magnitudes. Pool swimmers, short distances.
Review of motor and verbal learning experiments: conditions that maximise performance during practice can be detrimental to long-term retention and transfer, while some conditions that slow acquisition (e.g. variation) can enhance it. Laboratory tasks, not swimming; no prescription for specific sports.
External versus internal focus: performance, 73 studies, 1,824 participants, Hedges' g 0.264; learning, 40 studies, 1,274 participants, retention g 0.583 and transfer g 0.584. Age, health status and skill level did not moderate the effect. Mixed motor tasks, mostly not swimming; publication bias not reported in the abstract.
16 m front crawl. External cues (e.g. pushing the water back) produced shorter swim times than internal cues (e.g. pulling the hands back); in a second experiment external focus also beat a no-instruction control. Short sprint, intermediate swimmers; sample size not in abstract.
Three 25-yard lengths under external, internal and control conditions. Swim times were similar in control and external conditions and significantly slower with an internal (body-part) focus; swimmers who reported a body-part focus in the control condition swam more slowly than outcome-focused swimmers. External focus may be unnecessary for already automatic skills, but internal focus hampered performance.
Scoping review of 23 studies of motor-learning methods in children aged 5–12: 87% reported a positive effect during practice, but 87% lacked retention or transfer tests, 35% had no control or comparison group and 48% under-described the intervention; literature scarce and of questionable methodological quality. Children, not adults.