The influence of sleep, menstrual cycles, and training loads on heart rate variability : a four-year case study on an elite female slalom kayaker

Rauter, Samo (author), Novak, Ajda (author), Verdel, Nina (author)

This study aimed to examine the influence of training load, performance, sleep, and menstrual parameters on heart rate variability (HRV) and to evaluate its potential as a predictor of sports performance. A four-year longitudinal case study was conducted on a female elite kayak athlete, involving daily monitoring of HRV, sleep quality and duration, menstrual cycles, illnesses, and acute training loads. Over this period, 1394 measurements were taken each morning immediately after waking up and before getting up. The results of four competitive seasons were analyzed using a performance index and were statistically processed with a linear mixed model. The analysis revealed a statistically significant positive association between rMSSD and both sleep quality (p < 0.001) and the follicular phase of the menstrual cycle (p = 0.003). In contrast, the training load (p = 0.94), sleep duration (p = 0.27), and illness (p > 0.05) showed no statistically significant effect on rMSSD. Additionally, neither rMSSD (p = 0.82) nor its trend (p = 0.70) were significant predictors of the performance index. Despite the lack of a statistically significant correlation between HRV and sports performance, the findings suggest that the pre-competition decrease in HRV observed in this case study may reflect anticipatory physiological changes, potentially linked to increased sympathetic activation, as suggested in the existing literature.

• Language: English
• Keywords: sport, kayaker, female, heart rate variability, sports performance, longitudinal study, elite athlete, training load, sleep quality, menstrual cycle, physiological monitoring
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FŠ - Faculty of Sport
• Publication status: Published
• Publication version: Version of Record
• Year: 2025
• Number of pages: 11 str.
• Numbering: Vol. 15, iss. 7, art. 3806
• PID: 20.500.12556/RUL-183349
• UDC: 797.122.2
• ISSN on article: 2076-3417
• DOI: 10.3390/app15073806
• COBISS.SI-ID: 230886147
• Publication date in RUL: 11.06.2026

Record is a part of a journal

• Title: Applied sciences
• Shortened title: Appl. sci.
• Publisher: MDPI
• ISSN: 2076-3417
• COBISS.SI-ID: 522979353

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: šport, kajakaštvo, ženske, variabilnost srčnega utripa, športna uspešnost, longitudinalna študija, elitni športniki, vadbena obremenitev, kakovost spanja, menstrualni ciklus, fiziološko spremljanje

Projects

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P5-0147
• Name: Kineziologija monostrukturnih, polistrukturnih in konvencionalnih športov