Comment on: “Effects of Carbohydrate Mouth Rinse on Cycling Time Trial Performance: A Systematic Review and Meta-analysis” and Subsequent Comment/Author Reply from Li et al.

  • Fernando Klitzke BorszczEmail author
  • Ricardo Dantas de Lucas
Letter to the Editor

Dear Editor,

Recently, Brietzke et al. [1] presented a systematic review and meta-analysis on the effects of a carbohydrate (CHO) mouth rinse on cycling performance. This review received some criticism concerning the effects of the CHO mouth rinse in subjects in the fed and fasting states [2]. The authors replied to this criticism by including a new subgroup analysis for subjects who fasted overnight versus those in a restricted alimentary state [3]. Unfortunately, the review and letters contained substantial miscalculations and misinterpretations that could confuse the reader and lead to inaccurate conclusions. In the present letter, we discuss our three main concerns about the outcomes of Brietzke et al. [1, 3] and Li et al. [2].

Firstly, the authors stated that “A carbohydrate mouth rinse improves mean power output, but not the time to complete a cycling time trial” [1]. This statement could have been true if the time trial had been conducted outdoors, where environmental...


Compliance with ethical standards


No sources of funding were used to assist in the preparation of this letter.

Conflicts of interest

Fernando Klitzke Borszcz and Ricardo Dantas de Lucas declare that they have no conflicts of interest that are directly relevant to the content of this letter.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Fernando Klitzke Borszcz
    • 1
    Email author
  • Ricardo Dantas de Lucas
    • 1
  1. 1.Physical Effort Laboratory, Sports CentreFederal University of Santa CatarinaFlorianópolisBrazil

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