Normative data on regional sweat-sodium concentrations of professional male team-sport athletes

Abstract

Background

The purpose of this paper was to report normative data on regional sweat-sodium concentrations of various professional male team-sport athletes, and to compare sweat-sodium concentrations among sports. Data to this effect would inform our understanding of athlete sodium requirements, thus allowing for the individualisation of sodium replacement strategies. Accordingly, data from 696 athletes (Soccer, n = 270; Rugby, n = 181; Baseball, n = 133; American Football, n = 60; Basketball, n = 52) were compiled for a retrospective analysis. Regional sweat-sodium concentrations were collected using the pilocarpine iontophoresis method, and compared to self-reported measures collected via questionnaire.

Results

Sweat-sodium concentrations were significantly higher (p < 0.05) in American football (50.4 ± 15.3 mmol·L⁻¹), baseball (54.0 ± 14.0 mmol·L⁻¹), and basketball (48.3 ± 14.0 mmol·L⁻¹) than either soccer (43.2 ± 12.0 mmol·L⁻¹) or rugby (44.0 ± 12.1 mmol·L⁻¹), but with no differences among the N.American or British sports. There were strong positive correlations between sweat-sodium concentrations and self-reported sodium losses in American football (r _s = 0.962, p < 0.001), basketball (r _s = 0.953, p < 0.001), rugby (r _s = 0.813, p < 0.001), and soccer (r _s = 0.748, p < 0.001).

Conclusions

The normative data provided on sweat-sodium concentrations might assist sports science/medicine practitioners in generating bespoke hydration and electrolyte-replacement strategies to meet the sodium demands of professional team-sport athletes. Moreover, these novel data suggest that self-reported measures of sodium loss might serve as an effective surrogate in the absence of direct measures; i.e., those which are more expensive or non-readily available.

Keywords:

• Sweat
• Sodium
• Team-sport
• American football
• Basketball
• Baseball
• Soccer
• Rugby (3–10)

Acknowledgements

The authors wish to thank the study participants for their time and cooperation.

Funding

No funding was received.

Availability of data and materials

All data generated or analysed during this study are included in this published article.

Authors’ contributions

Conception and design of research (MKR, BD, AB); performed experiments (BD, AB, JT, RJ); analysed data (GR); interpreted results of experiments (GR, NBT, MKR); prepared figs. (GR, NBT); drafted manuscript (NBT, MKR); edited and revised manuscript (NBT, MKR); approved final version of manuscript (NBT, BD, AB, GR, MKR, JT, RJ).

Ethics approval and consent to participate

Ethical approval was received from Hartpury University Centre, and written, informed consent was received from all participants prior to data collection.

Consent for publication

Not applicable.

Competing interests

There were no conflicts of interest in the conception of this study or production of the manuscript. The results of the study are presented clearly, honestly, and without fabrication, falsification, or inappropriate data manipulation.

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