Effect of Physical Exercise on Motor Learning Acquired With Physical or Mental Practice

Motor learning is crucial for human daily routine, involving the acquisition of new movements. It consists of an online acquisition phase followed by offline consolidation, where motor memory is organized into stable representations. Acquisition can be achieved through physical practice (PP, overt repetition of movement) or mental rehearsal using motor imagery (MI). Recent studies suggest that high-intensity interval physical exercise (HIIE) enhances motor learning, particularly during consolidation, by promoting neural plasticity mediated by brain-derived neurotrophic factor (BDNF). However, the impact of HIIE on sequential motor consolidation with PP or MI remains poorly understood.

In contrast, sleep deprivation (SD) reduces BDNF release and neural plasticity. Limited research has explored the effects of SD on motor acquisition, especially sequential motor learning. Considering the opposing effects of HIIE and SD, performing HIIE after SD may protect motor consolidation processes.

This study aims to examine the influence of HIIE on sequential motor learning using PP or MI under both sleep-deprived and normal sleep conditions. Six groups, each comprising 12 participants, will learn an 8-item bimanual sequence.

* MI group: acquired the motor sequence mentally during training
* MI+HIIE group: acquired the motor sequence mentally and achieve a HIIE before the consolidation
* PP: acquired the motor sequence physically
* PP+HIIE group: acquired the motor sequence physically and achieve a HIIE before the consolidation
* SD+PP group: one night of sleep deprivation prior physical motor acquisition with PP and consolidation
* SD+PP+HIIE group: one night of sleep deprivation prior physical motor acquisition and HIIE before consolidation.

All groups will be tested on the sequence at the beginning and the end of the acquisition phase (pre- and post-acquisition), and after the physical exercise (i.e. HIIE) or the rest period (post-exercise).

Hypothesis of this study are :

* Acute physical exercise (HIIE) would enhance the consolidation of motor memory (post-exercise) after physical and mental acquisition (PP,MI) compared to conditions without exercise.
* One night of sleep deprivation would affect the acquisition and consolidation of motor learning.

Physical exercise would compensate for the detrimental effects of sleep deprivation on the consolidation of motor learning.

The ability to learn new movement (i.e. motor learning) is an essential part of the human daily routine. Motor learning is typically characterized by an online acquisition phase followed by an offline consolidation phase (i.e., without further practice) whereby the motor memory traces are reorganized into stable and long-lasting representations. The acquisition can be achieved through physical practice (PP, overt repetition of the movement) or through motor imagery (MI, covert rehearsal of movement). Over the last two decades, studies have demonstrated that performing high intensity interval exercise (HIIE) can enhance motor learning and particularly the consolidation phase. It seems that HIIE induced a favourable physiological cascade that contributes to the neural plasticity. In this vein, both lactate and brain derived neurotrophic factor (BDNF) biological markers seems to play a major role in long-term memory consolidation. To date, little is known on the HIIE contribution to sequential motor consolidation with PP or MI.

By contrast to HIIE, sleep deprivation decreased the BDNF released and the neural plasticity. There are very few studies that have examined the impact of sleep deprivation (SD) on motor acquisition and only one on sequence motor learning. Considering the antagonistic effects of HIIE and SD, it might possible that performing HIIE following SD could protect the motor consolidation processes.

Therefore, the main goal of this study is to understand the influence of HIIE on sequential motor learning through PP or MI under condition of sleep deprivation and normal night. In this study, six groups will be enrolled each including 12 participants. All groups will learn a bimanual sequence of 8 items.

* MI group: acquired the motor sequence mentally during training
* MI+HIIE group: acquired the motor sequence mentally and achieve a HIIE before the consolidation
* PP: acquired the motor sequence physically
* PP+HIIE group: acquired the motor sequence physically and achieve a HIIE before the consolidation
* SD+PP group: one night of sleep deprivation prior physical motor acquisition with PP and consolidation
* SD+PP+HIIE group: one night of sleep deprivation prior physical motor acquisition and HIIE before consolidation.

All groups will be tested on the sequence at the beginning and the end of the acquisition phase (pre- and post-acquisition), and after the physical exercise (i.e. HIIE) or the rest period (post-exercise).

Hypothesis of this study are :

* Acute physical exercise (HIIE) would enhance the consolidation of motor memory (post-exercise) after physical and mental acquisition (PP,MI) compared to conditions without exercise.
* One night of sleep deprivation would affect the acquisition and consolidation of motor learning.
* Physical exercise would compensate for the detrimental effects of sleep deprivation on the consolidation of motor learning.

Eligibility Criteria:
Inclusion Criteria:

* Male or female aged 18 to 35
* Available for the entire study (13 days maximum)
* Right-handed upper limbs with a score \> 0.5 on the Edinburgh laterality test
* Having dated and signed an informed consent
* Subject affiliated or entitled to a social security scheme
* Absence of contraindication to the practice of physical activity
* Considered active according to the GPAQ (Global Physical Activity Questionnaire)
* Neutral or moderate circadian typology (31 to 69)
* Regular physical activity (2h/week minimum)

Exclusion Criteria:

* Musculoskeletal injury \< 6 months
* Pathology or surgical intervention resulting in a locomotor disorder \< 6 months
* Chronic or disabling neurological, cardiovascular or psychic pathology
* Resting heart rate \> 100 bpm
* Pittsburgh Sleep Quality Index \> 10
* Taking sleeping pills or medication with a psychoactive effect during the last 6 months
* Ongoing participation in an interventional research
* Pregnant or breastfeeding women
* Person deprived of judicial or administrative freedom.
* Contraindication to TMS (Transcranial Magnetic Stimulation):
* Frequent or severe headaches
* History of epilepsy
* Head trauma with loss of consciousness
* Implanted equipment (including implanted pacemaker or defibrillator, cochlear implant, pump administering medication, surgical clips, metal shrapnel)
* Neurosurgical intervention (in particular eye surgery)
* An open wound on the scalp
* Consumption of more than three glasses of alcohol per day