Investigating the Effects of Time-of-day and Menstrual Cycle Phase (Low and High Progesterone) on Female's Cognitive and Strength Performance

NCT07399847 | Not Yet Recruiting

• 1 other identifier: FHM-2025-5797-RECR-2
• Study Type: observational
• Target: 30
• Locations: 0 countries
• Sites: N/A

Brief Summary

This study is designed to determine whether time-of-day and menstrual cycle phase influence athletic performance and is expected to contribute valuable insight into how both time-of-day, and hormonal factors can influence performance and expand existing research. This study aims to support more inclusive, effective and personalised approaches to training and competition schedules for female athletes. The study will involve two testing days that require a participant to complete a compilation of tests at 07:00, 12:00 and 18:00 hours. The testing days will be arranged for when a participant is in phase 1 (lowest levels of progesterone in the menstrual cycle) and phase 4 (highest level of progesterone in the menstrual cycle). The tests will examine a participant's executive function and physical strength. This study will aim to recruit thirty 18-30-year-old females from Lancaster University who identify with a sport that they train \~3 times a week for with a purpose to compete. The females recruited must have a regular menstrual cycle and no history of sleep disorders. Aim: To investigate the effects of time-of-day and menstrual cycle phase (low and high progesterone levels) on executive function and strength in females. Objectives:

1. 1.To determine the effects of time-of-day on executive function and strength tests.
2. 2.To determine the effects of menstrual cycle phase on executive function and strength tests.
3. 3.To examine if there is an interaction between time-of-day and menstrual cycle phase on executive function and strength tests.

Conditions

Circadian Rhythm; Menstrual Cycle Phase; Female Athletes; Executive Function (Cognition); Eumenorrhea; Strength

Outcome Measures

Primary Outcomes (1)

• Change in muscle strength with time-of-day and menstrual cycle phase

  Repeated measures of strength at 07:00, 12:00 and 18:00 hours in phase 1 and 4 of the menstrual cycle. Handgrip strength requires participants to maximally squeeze the dynamometer for 3-seconds. 3 repeats will be carried out with the participants dominant hand, with 1-minutes of rest between each, recording the maximal values to determine both peak and mean values. Participants would also perform both countermovement and squat jumps, measuring flight time (seconds) and vertical jump height (centimetres). Each jump type will be repeated 3 times with a rest interval of 30-seconds between each jump repetition and a 2-minute rest interval between jump types. Maximal isometric Voluntary contraction of knee extensors and flexors would be measured over 4-seconds at 60° flexion. Between away and towards contractions, participants will have 30-seconds and between each set, they will have 3-minutes passive recovery.

  07:00, 12:00 and 18:00 hours in phase 1 and 4 (the points of low and high progesterone) of the menstrual cycle (each cycle is 21-35 days). Phase 1 is during menstruation and phase 4 is +7 days (±1) after the confirmation of the luteinising hormone peak.

Secondary Outcomes (20)

• Change in cognitive performance with time-of-day and menstrual cycle phase

  07:00, 12:00 and 18:00 hours in phase 1 and 4 (the points of low and high progesterone) of the menstrual cycle (each cycle is 21-35 days). Phase 1 is during menstruation and phase 4 is +7 days (±1) after the confirmation of the luteinising hormone peak.

• Change in menstrual cycle symptoms with time-of-day and menstrual cycle phase

  07:00, 12:00 and 18:00 hours in phase 1 and 4 (the points of low and high progesterone) of the menstrual cycle (each cycle is 21-35 days). Phase 1 is during menstruation and phase 4 is +7 days (±1) after the confirmation of the luteinising hormone peak.

• Ovulation phase confirmation

  Prior to testing visit and the following menstrual cycle. The day to begin ovulation testing varies depending on menstrual cycle length (21-35 days) but typically will begin around day 10 of each cycle, with day 1 being the first day of bleeding.

• Change in participant weight with time-of-day and menstrual cycle phase

  07:00, 12:00 and 18:00 hours in phase 1 and 4 (the points of low and high progesterone) of the menstrual cycle (each cycle is 21-35 days). Phase 1 is during menstruation and phase 4 is +7 days (±1) after the confirmation of the luteinising hormone peak.

• Change in hormone levels with time-of-day and menstrual cycle phase

  07:00, 12:00 and 18:00 hours in phase 1 and 4 (the points of low and high progesterone) of the menstrual cycle (each cycle is 21-35 days). Phase 1 is during menstruation and phase 4 is +7 days (±1) after the confirmation of the luteinising hormone peak.

Study Arms (1)

Female participants

Female (assigned at birth), aged 18-30 years. They must be tier 2 athletes which requires the participants to identify with a sport, train with a purpose to compete, regularly train \~3 times per week and compete at a local level. The participants must have a regular menstrual cycle - considered between 21-35-day cycles with at least 9 periods a year. Participants must not be currently/previously (in the last 3 months) using of any contraceptive method that alter the menstrual cycle or used the emergency contraceptive pill either 3 months prior to the study or during the study.

Eligibility Criteria

• Age: 18 Years - 30 Years
• Sex: female
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

Participants will be selected from across Lancaster University (staff and students)

You may qualify if:

• Female (assigned at birth)
• Aged 18-30 years
• Tier 2 athlete which requires the participants to identify with a specific sport, train with a purpose to compete, regularly train \~3 times per week and compete at a local level (for example being a member of a BUCS sport and competing regularly with that sport)
• Regular menstrual cycle - considered between 21-35-day cycles with at least 9 periods a year.

You may not qualify if:

• The current/previous (in the last 3 months) use of any contraceptive method that alter the menstrual cycle
• The use of the emergency contraceptive pill either 3 months prior to the study or during the study
• Diagnosis of menstrual disorders including (but not exclusively) endometriosis and Polycystic Ovary Syndrome (PCOS)
• A formal diagnosis of sleep disorders such as insomnia
• Consume \>400mg/day of caffeine
• A musculoskeletal injury in the past 3 months
• A formal diagnosis of neurological or psychiatric disorders such as Attention-Deficit/Hyperactivity Disorder (ADHD), Autism Spectrum Disorder (ASD), Dyslexia or schizophrenia
• Taking prescribed medication that may affect sleep for example stimulants such as Methylphenidate
• No regular night shift work
• No trans-meridian travel within 10 days of their expected participation dates (travel that will cause jetlag)

Sponsors & Collaborators

• Lancaster University: lead
• Liverpool John Moores University: collaborator

Biospecimen

Retention: SAMPLES WITHOUT DNA

Participants will have 90ml of bloods taken from their arm over the course of the study to measure levels of progesterone (P2), oestrogen (E2), inflammatory markers (Interleukin 6 (IL-6), Tumour necrosis factor alpha (TNF-alpha) and High-sensitivity C-reactive protein (hsCRP)) and for omics analysis. The blood will be centrifuged down and blood serum will be analysed.

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Senior Lecturer in Integrative Physiology

Study Record Dates

• First Submitted: January 13, 2026
• First Posted: February 10, 2026
• Study Start: February 1, 2026
• Primary Completion (Estimated): June 1, 2026
• Study Completion (Estimated): September 1, 2026
• Last Updated: February 10, 2026

Record last verified: 2026-02