Speedo Junior Fastskin LZR HyperPro Kneesuit Size Guide

This size guide covers the Speedo Fastskin LZR HyperPro Kneeskin — Girls' Junior, a World Aquatics approved competition racing kneeskin available in sizes 26–32 (ages 7–14). The LZR HyperPro delivers all-day comfort combined with moderate compression, engineered to work in synergy with the swimmer and built to last race after race. Designed for all ages, skill levels, strokes and distances.

Key features include comfortable compression engineered for comfort and performance, optimised seamlines and bonded dual layers designed and engineered for fit, flexibility and performance, flexible comfort straps anchored with precision to provide stability and a comfortable, unrestricted fit, and shape-retaining lightweight fabric with durable wrapped yarns and water repellant coating — built to last race after race. Fully approved by World Aquatics and developed by Speedo Aqualab. All measurements are body measurements taken from your child's body, not garment measurements.

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Body Measurement Points
Speedo LZR HyperPro Junior Kneeskin body measurement points — body loop, chest, waist and hip diagram for girls
How to Measure

To find the correct LZR HyperPro Kneeskin size, use a soft measuring tape and take all measurements directly against your child's skin. Age is shown as a guide only — always use body measurements, as children develop at very different rates. The Body Loop is the most important measurement for a kneeskin.

  • A
    Body LoopMeasure over one shoulder, down the front, under the crotch and back up to the same shoulder. This gives the torso length needed for a kneeskin.
  • B
    HipMeasure at the widest part of the hips and seat, keeping the tape horizontal.
  • C
    ChestMeasure across the fullest part of the chest, keeping the tape horizontal.
  • D
    WaistMeasure at the narrowest part of the natural waist.

Note: Ages shown in the sizing table are a guide only. Always use body measurements to select the correct size. Children of the same age can vary significantly in size.

Sizing Table — Girls' Fastskin LZR HyperPro Kneeskin
Size 26 Size 28 Size 30 Size 32
Age (guide only) 7–8 yrs 9–10 yrs 11–12 yrs 13–14 yrs
Body Measurements
Body Loop cm 117–124 125–132 133–140 141–145
Chest cm 66.0–70.0 71.0–74.0 75.0–79.0 80.0–84.0
Waist cm 59.0–61.5 62.0–64.5 65.0–67.0 68.0–70.0
Hip cm 70.0–74.5 75.0–79.5 80.0–84.5 85.0–89.5

Ages shown are a guide only. Always use body measurements to select the correct size. All measurements are body measurements, not garment measurements.

Fit Notes — Speedo Fastskin LZR HyperPro Kneeskin (Girls')
  • The LZR HyperPro Kneeskin uses moderate compression engineered for all-day comfort and performance — it will feel firmer than a training suit but is designed to be worn comfortably throughout a full competition day, making it an excellent choice for junior swimmers at any level.
  • Always use body measurements to select the correct size — the age guide is indicative only, as children develop at very different rates.
  • The Body Loop is the most important measurement for a kneeskin — always measure this first. If measurements fall across different size brackets, use the Body Loop as the primary guide.
  • The flexible comfort straps should sit flat across the shoulders with no pulling, twisting, or rubbing. They are anchored with precision to provide stability and a comfortable, unrestricted fit throughout the competition day.
  • The suit should be completely wrinkle-free when correctly fitted. Any bunching or gathering indicates the suit is too large.
  • The bonded dual layers and optimised seamlines should lie flat against the skin with no rubbing or pressure points at any point during racing.
  • The leg hems should end above the knee in line with WA regulations and feel snug but not restrict movement or blood flow.
  • Allow 10–15 minutes to try on correctly for the first time. Take care with fingernails and jewellery when pulling on the suit to protect the water repellant coating.
  • Do not use petroleum-based products, oils, or creams before putting on the suit — these degrade the water repellant coating.
  • Rinse in cold fresh water immediately after each use. Do not tumble dry, iron, or dry-clean.
  • Unsure? Contact our team or call +44 1827 330600. Speak to a member of staff at Allens if you are unsure.
Frequently Asked Questions — Speedo Fastskin LZR HyperPro Kneeskin (Girls')

Yes. The Speedo Fastskin LZR HyperPro Kneeskin is fully approved by World Aquatics (WA) and is legal for use in all sanctioned competitive swimming events. It has been developed by Speedo Aqualab and is built to compete at all levels of the sport. Always check with your event organiser for any local age group rules regarding tech suits in competition.

The LZR HyperPro Junior Kneeskin is available in sizes 26 to 32, covering an approximate age range of 7 to 14 years. However, age is a guide only — always use body measurements to select the correct size, as children of the same age can vary significantly in size. If your child's measurements fall between two sizes, speak to a member of staff at Allens for guidance.

The Body Loop is measured by running a soft tape measure over one shoulder, down the front of the body, under the crotch, and back up to the same shoulder. This is the most important measurement for a kneeskin as it determines the torso length and whether the flexible comfort straps will sit correctly on the shoulders without pulling during competition.

Always select by body measurements. The age ranges shown are a guide only — children develop at very different rates and age alone is not a reliable indicator of the correct size. Measure the body loop, chest, waist, and hip and compare to the sizing table above, using the body loop as the primary guide. Speak to a member of staff at Allens if you are unsure.

The LZR HyperPro Kneeskin should feel firm and compressive but comfortable throughout a full competition day. The flexible comfort straps should sit flat on the shoulders with no pulling or rubbing, the bonded seamlines should lie flat with no rubbing, and the suit should be completely wrinkle-free when correctly fitted. The leg hems should sit above the knee in line with WA regulations.

The Speedo Fastskin LZR HyperPro Kneeskin is designed for all competitive swimming events and all four strokes. It is specifically engineered to suit all skill levels, strokes and distances — making it an ideal choice for junior swimmers competing at club, county, or regional level who want a reliable, comfortable racing kneeskin that performs race after race.

Yes. The LZR HyperPro Kneeskin's moderate compression and all-day comfort make it an excellent choice for a junior swimmer's first Fastskin racing suit. The flexible comfort straps are anchored with precision to reduce rubbing and provide a comfortable, unrestricted fit throughout a full competition day, making it much easier to wear compared to higher compression suits.

The LZR HyperPro sits within the Fastskin racing range and is designed to deliver all-day comfort with moderate compression, suitable for all skill levels and distances. It features flexible comfort straps, optimised seamlines, bonded dual layers, and a shape-retaining lightweight fabric built to last race after race — engineered to work in synergy with the swimmer and developed by Speedo Aqualab.

The LZR HyperPro Kneeskin is a competition racing suit and is not designed for regular training use. Using it for training will degrade the water repellant coating and shorten the lifespan of the suit. Reserve it for races and competition warm-ups to maintain its performance. Speedo offer a wide range of junior training swimsuits for everyday training use.

Rinse the suit thoroughly in cold fresh water immediately after every use to remove chlorine and salt. Do not machine wash, tumble dry, iron, or dry-clean. Store the suit flat and dry, away from direct sunlight. Avoid contact with sun cream or petroleum-based products as these degrade the water repellant coating. Regular care after each use is essential to maximise the lifespan of the suit.