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César Cielo

Guinness names César Cielo's 20.91 from 2009 as the mark McEvoy broke. The all-time list dates it 18 December 2009 in São Paulo.

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Race time

20.91s

Long-course men's 50 m freestyle, São Paulo. Personal best, not a short-course time.

OfficialGuinness World Records (opens source in a new tab)

Mechanism

Why it's so fast

César Cielo's 50 metre freestyle is mostly the start, the underwater kicks, and a few strokes. The pool ends before a long swim would. The clock on this page is the one the all-time list prints.

  1. Underwater

    The fastest part of a one-length race is often under the surface, away from the drag of the air-water line. The rules limit how far that phase may last, which is why the stroke still matters.

  2. The dive

    César Cielo's reaction and entry are a large share of 50 metres. A slow start is not recovered over a single length.

  3. The surface that is left

    Once the swimmer is up, stroke rate and a straight body line decide the rest. Extra drag from a poor position costs time immediately.

Nearby on this list: Cameron McEvoy.

Provenance

Every measurement

Claimed, measured and official figures side by side, each with its source. The ranked figure is marked.

  1. 20.91sRanked figure

    Long-course men's 50 m freestyle, São Paulo. Personal best, not a short-course time.

    World Aquatics' McEvoy story says Cielo's record had stood since December 2009. The all-time table prints 18 December 2009 in São Paulo. Textile-suit rules changed in 2010; the mark stayed on the ratified list.

    Official
    Guinness World Records (opens source in a new tab)

Reference

Specs

Country
Brazil
Event
50 m freestyle, long course
Time
20.91 s
Date
18 December 2009

Context

Background

Guinness names César Cielo's 20.91 from 2009 as the mark McEvoy broke. The all-time list dates it 18 December 2009 in São Paulo.

World Aquatics' McEvoy story says Cielo's record had stood since December 2009. The all-time table prints 18 December 2009 in São Paulo. Textile-suit rules changed in 2010; the mark stayed on the ratified list.

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