https://thetriathlete.co.uk/sessions/swim-efficiency-circuit-swolf-css-45min-session/
Swim Efficiency Circuit: SWOLF Test and CSS Speed Blocks - The Triathlete
Measure your swim efficiency with the SWOLF test then build CSS speed in one 45-minute pool session. A smart swim workout for triathletes of all levels.
swimefficiencycircuitswolftest