Runners and cyclists often have stiff ankles, and ankle range is linked to kick speed. But the kick adds little to front crawl speed at triathlon pace, and no trial shows stretching makes adult swimmers faster.
High-intensity swim training improves fitness in competitive swimmers, mostly young pool sprinters. What the trials and meta-analyses show, why they say little about 3.8 km, and how much fast swimming a long-course triathlete needs.
How to structure limited pool time so it builds speed as well as endurance: what goes in a 45-minute session, how much rest to take, where drills and toys fit, and how to rotate session types across a week.
Myth: an Ironman swimmer only needs long, steady volume.
Myth: it's a non-drafting bike, so who you exit the swim with is irrelevant.
Myth: don't kick — save your legs for the bike.