ESTIMATING STUDY SAMPLE SIZE AND ASSESSING RELIABILITY OF PEAK FAT OXIDATION (PFO) DATA (G/MIN) COLLECTED DURING FATMAX TESTS, WITH CONSIDERATION FOR MENSTRUAL CYCLE IN ENDURANCE-TRAINED WOMEN

Autor(i)

  • Eoin Molloy Post-Graduate Research Student, South East Technological University, Ireland
  • Maria Murphy-Griffin Lecturer, Dr, Department of Sport & Exercise Science, South East Technological University, Ireland
  • Michael Harrison Head of Department of Sport & Exercise Science, South East Technological University, Ireland

DOI:

https://doi.org/10.46827/ejpe.v12i2.5784

Ključne riječi:

FATMAX, sample size estimation, peak fat oxidation, reliability

Sažetak

Background: Sample size estimations are completed to determine the number of participants needed to highlight a relevant treatment effect [1]. This is crucial to ensure that the results are reliable. Estimating sample size can also assist researchers by informing the financial outlay for a project and minimising any over spend. Purpose: In this study, different methods to estimate sample size using PFO data were utilised. PFO data collected using the test re-test method was employed to estimate sample size. PFO results from previous research were also applied to estimate sample size [2,3,5,6]. Methods: Subsequently, a group of endurance-trained women (n=5) aged 36 (+/- 2.4 years) were recruited from the main study. Menstrual cycle (MC) length was established and within the MC, the mid-follicular phase (MF) (low hormone phase) was determined [4]. Identifying the MF phase of the MC would allow for FATMAX test re-test’s to be conducted when sex hormones were least likely to change or impose an effect on substrate utilisation. Tests were separated by 24 hours to allow participants to recover, to ensure hormonal change was minimal and to test the reliability of the results collected. Results: Results from previous research were statistically analysed individually and in group form to estimate sample size. When analysing PFO data from previous research, a mean sample estimation of 7 participants was suggested. Test re-test PFO results were assessed for reliability (ICC=0.82) before sample size estimations were conducted. Individual analysis from the test re-test method outlined a mean sample estimation of 14 participants, and group analysis from this method suggested a mean sample estimation of 14 participants. An overall mean sample from all estimations outlined a sample size of 12 participants.

Acknowledgement

The above article was conducted in paralell as a relaibility study for the article titled “Investigsating the effects of hormonal fluctuations associated with menstrual cycle on peak fat oxidation during graded exercise” which was published in a previous edition of the European Journal of Physical Education and Sport Science, Volume 11, Issue 7. https://oapub.org/edu/index.php/ejep/article/view/5715

 

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Biografije autora

  • Eoin Molloy, Post-Graduate Research Student, South East Technological University, Ireland

    Eoin Molloy PhD(c) began his studies at Waterford Institute of Technology, Waterford, Ireland, from which he holds a BSc (Hon 1:1) in Sports Coaching and Performance. Upon graduating from WIT, Eoin continued his studies and completed a Post graduate Diploma in Performance Nutrition (with Distinction) through the Institute of Performance Nutrition. Whilst completing his PgDip, Eoin decided to also set out on the PhD track investigating performance and health markers of fasted training on female recreational endurance athletes. The aim of Eoin’s research is to gain a better understanding of the effects of fasted training and the menstrual cycle phase on endurance performance and substrate utilisation in female athletes. The objective is to clearly demonstrate the importance of female-specific training programs derived from female-specific research.

  • Maria Murphy-Griffin, Lecturer, Dr, Department of Sport & Exercise Science, South East Technological University, Ireland

    Dr. Maria Murphy-Griffin is a full-time lecturer in the department's undergraduate programmes since 2002. She is interested in both exercise for health and in sport and performance and has a particular interest in exercise/sport physiology. Dr. Maria Murphy-Griffin has been awarded a BA in Physical Education and Mathematics (UL), an MSc in Sports Science (Loughborough University, Leics) and a PhD in Exercise and the Heart (UL).

  • Michael Harrison, Head of Department of Sport & Exercise Science, South East Technological University, Ireland

    Professor Michael Harrison has worked at WIT since 1999.  He is the Head of the Department of Sport and Exercise Science and a former Dean of the School of Science and Computing. Michael’s research, undertaken in conjunction with University Hospital Waterford and UPMC Whitfield, considers the impact of exercise on clinical populations, including age-related frailty, vascular disease and cancer.  He has a specific interest in immune cell subsets that exert positive and negative influences on the processes that underlie ageing and vascular disease. Michael is Chair of the Register of Exercise Professionals in Ireland and sits on the Professional Standards Committee of the European Register of Exercise Professionals.  He has been part of different national working groups and local initiatives to establish community-based exercise services for individuals with chronic health conditions and sits on the Advisory Board of the Exercise is Medicine Ireland National Centre.  Michael holds a Fellowship from the American College of Sports Medicine. 

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2025-01-28

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Svezak 12 Br. 2 (2025)

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