Saturday Swim Session: Natasha Van Der Merwe's Beginner Speed Focus Session
Swimming, July 25, 2026
The **Build, Hold & Finish Strong** swim session is designed to improve your ability to change pace while maintaining efficient freestyle technique. With three workout options (1,850m, 2,300m and 3,200m), you'll develop speed control, aerobic endurance and active recovery through a combination of build sets, short intervals and alternating fast and easy swimming. Ideal for triathletes, masters swimmers and recreational swimmers looking to become stronger, more versatile and more confident in the pool.
This week's session is all about learning to change gears in the water. You'll gradually build your speed, practise holding good technique at faster paces, then learn to recover while still swimming efficiently. By alternating fast and controlled efforts, you'll improve your ability to surge when required without sacrificing your stroke. It's an ideal session for triathletes, masters swimmers and recreational swimmers looking to become stronger and more versatile in the pool.
Before you begin, I recommend reading my article explaining Swim Intensity, as it will help you understand how hard each part of the workout should feel and how to pace each repetition appropriately.
Today's Goal
Develop the ability to change pace while maintaining efficient freestyle technique. The aim is not simply to swim fast, but to accelerate smoothly, recover under control and finish each set with good body position and consistent stroke mechanics.
Why You're Doing This Session
Many swimmers can comfortably maintain one pace but struggle when they need to accelerate or recover without stopping. This session develops both aerobic endurance and speed endurance by repeatedly changing intensity throughout the workout.
The build sets teach you how to increase speed progressively rather than sprinting too early. The shorter 50m repetitions reinforce good technique at higher stroke rates, while the fast/easy intervals teach your body to recover while still swimming. This is particularly valuable for open water swimmers and triathletes who often need to respond to changes in pace, navigate around other competitors or accelerate around buoys before settling back into a sustainable rhythm.
Session Inspiration
The inspiration for this week's session came from an Instagram reel by professional triathlete Natasha Van Der Merwe. Rather than reproducing her workout, I've adapted the structure and modified the distances to create a session that's appropriate for recreational swimmers, age-group triathletes and masters swimmers. The result captures the same training principles while making the session achievable for a wide range of abilities.
Today's Workout
Option A (1,850m)
- 150m Warm Up (WU)
- 150m Kick (K)
- 150m Pull Buoy & Paddles (PP)
- 4 × 50m Build 1-4 (10 sec RI)
- 6 × 50m (10 sec RI)
- 3 × 100m (50m Fast / 50m Easy) (20 sec RI)
- 1 × 300m (50m Fast / 50m Easy)
- 200m Swim Cool Down
- 100m Kick
Option B (2,300m)
- 200m Warm Up (WU)
- 200m Kick (K)
- 200m Pull Buoy & Paddles (PP)
- 4 × 50m Build 1-4 (10 sec RI)
- 8 × 50m (10 sec RI)
- 4 × 100m (50m Fast / 50m Easy) (20 sec RI)
- 2 × 200m (50m Fast / 50m Easy) (30 sec RI)
- 200m Swim Cool Down
- 100m Kick
Option C (3,200m)
- 300m Warm Up (WU)
- 300m Kick (K)
- 300m Pull Buoy & Paddles (PP)
- 4 × 50m Build 1-4 (10 sec RI)
- 12 × 50m (10 sec RI)
- 6 × 100m (50m Fast / 50m Easy) (20 sec RI)
- 3 × 200m (50m Fast / 50m Easy) (30 sec RI)
- 200m Swim Cool Down
- 100m Kick
What You Should Focus On
- Build your speed progressively rather than sprinting too early.
- Maintain a long, efficient stroke as your pace increases.
- Swim the "easy" sections with purpose—they're active recovery, not rest.
- Keep your kick controlled and avoid excessive splashing.
- Hold good body position throughout every set, regardless of speed.
Common Mistakes To Avoid
- Swimming the first build repetition too fast.
- Turning the easy 50m sections into complete recovery swims.
- Losing technique as stroke rate increases.
- Taking longer rests than prescribed.
- Relying on the kick instead of maintaining strong upper-body propulsion.
Tips For Completing The Workout Successfully
If you're using paddles, choose a comfortable size that allows you to focus on technique rather than brute force.
For the kick sets, I recommend swimming without a kickboard. This encourages better body alignment and a more natural kicking action. If you're unfamiliar with kicking without a board, the following video explains the technique well:
During the build repetitions, think about increasing your speed by improving the quality of each stroke rather than simply spinning your arms faster.
Finally, don't neglect the easy sections. They teach your body to recover while still swimming, an important skill for endurance events.
Workout Breakdown
For the Warm Up (WU) start with 150m (Option A), 200m (Option B) or 300m (Option C) of mixed swimming, include a range of strokes. During the warm-up feel free to stop and stretch as needed. It doesn’t need to be a continuous swim.
Next up is a further 150m (Option A), 200m (Option B) or 300m (Option C) of Kick. Avoid using a kickboard for the kick (see the video below).
Continue the sessions with a further 150m (Option A), 200m (Option B) or 300m (Option C) of Pull Buoy and Paddles.
The next set is made up of four 50m reps. Build your pace with each subsequent rep. Start with a moderate pace, then a fast pace for the second rep, a faster rep for the third and the final rep will be your fastest. Take a ten second Rest Interval after each rep.
The following set is made up of six (Option A), eight (Option B) or twelve (Option C) reps of 50m. Take a ten second Rest Interval after each rep.
The next set is made up of three (Option A), four (Option B) or six (Option C) reps of 100m. Start these reps with the first 50m fast, then cruise the last 50m of each rep. Take a twenty second Rest Interval after each rep.
The final set is made up of one (Option A), two (Option B) or three (Option C) reps of 300m (Option A) or 200m (Options B & C).
Complete the workout with a 300m Cool Down (CD) made up of 200m swimming then 100m of Kick to finish with. As with earlier in the workout avoid using a kickboard for the kick (see the video above).
After Your Swim
Take a minute to reflect on today's session.
Ask yourself:
- Did I build my speed smoothly during the build repetitions?
- Could I recover effectively during the easy swimming?
- Did my technique remain consistent during the faster efforts?
- Which part of the workout challenged me the most?
The answers will help guide your focus during future sessions.
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