45-Minute Swim Kick Set: Build Your Lower Body in the Pool

Session Overview

This 45-minute kick-focused swim session develops lower body propulsion, improves ankle flexibility, and teaches you to maintain a streamlined body position — all critical for efficient open water and pool swimming. Most triathletes underutilise their kick; this session addresses that gap and helps you build a more balanced freestyle technique.

What You’ll Need

• Kickboard (standard foam pool equipment — most pools provide them)
• Fins (optional but helpful for the technique drills)
• Pool access, 25m
• Goggle

Warm-Up (8 minutes)

Swim 200m easy freestyle — no kickboard yet — focusing on a gentle 2-beat kick (one kick per arm stroke). Then do 4 x 25m flutter kick on your back without a board, arms by your sides, looking up at the ceiling. This activates your kick without the hip restriction of holding a board in front of you.

Main Set

Use the kickboard for the main effort sets. Hold the board at arm’s length, keep your face in the water between breaths (don’t look forward — look down), and kick from the hip, not the knee. Toes should be pointed (plantar flexed) and ankles relaxed — your feet create propulsion when the leg drives down and the foot flicks at the bottom of the motion.

• 4 x 50m kickboard, steady effort, 20 seconds rest — establish a consistent 6-beat kick and count your strokes per length
• 4 x 25m kickboard sprint, maximum effort, 30 seconds rest — explosive kick sets build fast-twitch ankle flexor strength
• 4 x 50m kickboard with fins (if available), easy effort, 15 seconds rest — fins allow greater propulsive force and help train ankle plantarflexion
• 2 x 100m full freestyle, focus on integrating your kick with arm stroke, 30 seconds rest — bring it all together

Cool-Down (5 minutes)

Swim 150m easy backstroke — no board, easy flutter kick. Backstroke opens up your hip flexors, which may feel tight after extended kickboard work. Finish with 50m easy freestyle, arms only, no kick, to relax the legs completely before exiting the pool.

Coaching Notes

• If your kick is very weak, you’ll move slowly on the board and your legs may sink — this is normal for new swimmers and means the session is working exactly the muscles you need to develop. Don’t be discouraged.
• Stiff ankles are the number one limiter of kick efficiency. Off-pool, practice ankle circles daily and spend time sitting with ankles extended (like a ballet point position) to improve your plantarflexion range.
• Easier version: Use fins for the entire session instead of just the fin drill. Fins compensate for weak kick while still loading the muscles in a useful way.
• Target: Most triathletes should aim for a 2-beat kick during distance swimming (conserves energy for the bike and run) but having a strong 6-beat kick as a tool for the final sprint or when being overtaken in a race pack is extremely useful.