Diurnal variation in swim performance remains, irrespective of training once or twice daily

Louise Martin, Alan M Nevill, Kevin G Thompson

    Research output: Contribution to journalArticlepeer-review

    19 Citations (Scopus)


    PURPOSE: Fast swim times in morning rounds are essential to ensure qualification in evening finals. A significant time-of-day effect in swimming performance has consistently been observed, although physical activity early in the day has been postulated to reduce this effect. The aim of this study was to compare intradaily variation in race-pace performance of swimmers routinely undertaking morning and evening training (MEG) with those routinely undertaking evening training only (EOG).

    METHODS: Each group consisted of 8 swimmers (mean +/- SD: age = 15.2 +/- 1.0 and 15.4 +/- 1.4 y, 200-m freestyle time 132.8 +/- 8.4 and 136.3 +/- 9.1 s) who completed morning and evening trials in a randomized order with 48 h in between on 2 separate occasions. Oral temperature, heart rate, and blood lactate were assessed at rest, after a warm-up, after a 150-m race-pace swim, and after a 100-m time trial. Stroke rate, stroke count, and time were recorded for each length of the 150-m and 100-m swims.

    RESULTS: Both training groups recorded significantly slower morning 100-m performances (MEG = +1.7 s, EOG = +1.4 s; P < .05) along with persistently lower morning temperatures that on average were -0.47 degrees C and -0.60 degrees C, respectively (P < .05). No differences were found in blood-lactate, heart-rate, and stroke-count responses (P > .05). All results were found to be reproducible (P > .05).

    CONCLUSIONS: The long-term use of morning training does not appear to significantly reduce intradaily variation in race-pace swimming or body temperature.

    Original languageEnglish
    Pages (from-to)192-200
    Number of pages9
    JournalInternational Journal of Sports Physiology and Performance
    Issue number2
    Publication statusPublished - Jun 2007


    Dive into the research topics of 'Diurnal variation in swim performance remains, irrespective of training once or twice daily'. Together they form a unique fingerprint.

    Cite this