Morning versus late-afternoon aerobic exercise: effects on sleep in endurance athletes and inactive people

Effects of Exercise Timing and Physical Activity Level on Sleep Quality and Body Temperature

This trial will test if doing aerobic exercise in the morning versus the late afternoon changes deep sleep, how quickly you fall asleep, and core body temperature in endurance athletes and inactive adults.

Quick facts

• Phase: Not applicable
• Study type: Interventional
• Enrollment: 42 (estimated)
• Ages: 18 Years to 30 Years
• Sex: All
• Sponsor: Centre Hospitalier Universitaire de Saint Etienne (Academic / other)
• Locations: 1 site (Saint-Etienne)
• Trial ID: NCT07322276 on ClinicalTrials.gov

What this trial studies

Participants who are either endurance-trained athletes or inactive, sedentary adults will be assigned to perform standardized aerobic exercise sessions in the morning or late afternoon. The study will record sleep architecture with emphasis on deep sleep and sleep onset latency, and will continuously monitor core body temperature and autonomic markers such as heart rate variability. Investigators will compare effects of exercise timing within and between the two participant groups to determine whether training status modifies these responses. The protocol involves supervised in-person exercise sessions and physiological monitoring at a single center.

Who should consider this trial

Good fit: Healthy adults who are either endurance-trained athletes (specializing in aerobic exercise with >300 minutes/week for at least 6 months and regional-level participation) or inactive/sedentary adults who do not meet WHO exercise recommendations, and who do not have excluded medical or sleep conditions.

Not a fit: People with diagnosed sleep disorders, significant medical conditions (renal, respiratory, cardiovascular, neuromuscular), current mental health conditions requiring treatment, or who are pregnant or breastfeeding are excluded and unlikely to benefit.

Why it matters

Potential benefit: If positive, the findings could guide when people should schedule aerobic workouts to improve deep sleep and recovery.

How similar studies have performed: Previous research shows regular exercise can improve sleep overall, but evidence about the specific effects of exercise timing on deep sleep and core temperature is mixed and relatively limited.

Eligibility criteria

Inclusion Criteria:

* Group "Inactive" :No regular exercise practice (inactive people that don't follow the WHO recommendations) and have sedentary behaviors
* Group "Active": Regular exercise (athletes that are specialized in aerobic exercise, with more than 300 minutes per-week over 6 months and practice at regional level).

Exclusion Criteria:

* Have sleep disorders medically diagnosed or detected by sleep forms cutoffs (clinical insomnia by ISI, severe risk of obstructive sleep apnea by Stop-Bang, bad sleep quality by PSQI.
* Have a diagnosed mental health condition requiring treatment
* Have renal, respiratory, cardiovascular or neuromuscular disease medically diagnosed.
* Be pregnant or breastfeeding

Where this trial is running

Saint-Etienne

• Chu Saint-Etienne — Saint-Etienne, France (Recruiting)

Study contacts

• Principal investigator: Frédéric ROCHE, PhD — Centre Hospitalier Universitaire de Saint Etienne
• Study coordinator: Frédéric ROCHE, PhD

Conditions Healthy Endurance Athlet; Inactive People; endurance athletes; exercise timing; sleep quality