Aerobic Physical Activity and Orofacial Myofascial Pain

Temporal summation (TS) will be assessed by applying repetitive stimuli in the form of blunt needle pricks (pinprick) to the skin overlying the forearm muscles. The intensity of the pinprick will be individually calibrated to induce a baseline pain of 20/100 on a Numerical Rating Scale (NRS). Participants will be asked to rate the intensity of the pain provoked by the pinprick. The examiner will first apply a single stimulus, followed by a series of 10 stimuli applied at a frequency of 1 Hz over an area of 1 cm². Pain will be assessed verbally using a numerical rating scale ranging from 0 to 100, with anchors at 0 ('no pain') and 100 ('worst imaginable pain'). The entire procedure will be repeated three times. For the pinprick stimulations, the magnitude of temporal summation (ΔTSP = pain score at the 10th stimulation - pain score at the 1st stimulation) will be calculated.

The assessment of referred sensation (RS) will be performed using mechanical stimulation. A force of 0.5 and 2.0 kg will be applied to the masseter muscle using a palpometer (Palpeter; Sunstar Suisse SA, Etoy, Switzerland). The stimulation will be repeated 5 times. Each individual mechanical stimulation will last 5 seconds, followed by a 10-second interval allowing the participant to rate the intensity of the sensation and report any RS. Mechanical sensitivity will be evaluated on an NRS scale of 0-50-100 (where 0 corresponds to no sensation, 1-49 to a non-painful sensation, 50 to the pain threshold, and 100 to the most painful sensation). Sensations will be considered referred if the participant reports a sensation extending beyond the boundary of the masseter muscle. If such a sensation occurs, the participant will be asked to point to the location where the sensation was felt, and the examiner will determine if this location lies outside the masseter muscle limits. If participants

Anxiety will be assed by GAD-7 questionnaire ; a 7-item self-administered questionnaire used as a screening tool and a measure of the severity of generalized anxiety disorder. It calculates the score by assigning 0, 1, 2, or 3 points to the response options 'not at all', 'several days', 'more than half the days', and 'nearly every day', respectively. The total score for the GAD-7 questionnaire ranges from 0 to 21 points.

If GAD-7 score is less than 4 : absence of anxiety, between 5 and 9 : mild anxiety, between 10 and 14 : moderate anxiety and superior than 15 : significant severe anxiety.

Depression will be evaluated by PHQ-4 , a self-administered screening tool designed to score anxiety and depression, both of which are significant risk factors for the chronification of pain. The first two items assess anxiety, while the last two assess depression. Each item is scored from 0 to 3 (0 for 'not at all', 1 for 'several days', 2 for 'more than half the days', and 3 for 'nearly every day').

If PHQ-4 score is less than 2 : absence of psychological distress, between 3 and 5 : mild psychological distress, between 6 and 8 : moderate psychological distress and superior than 9 : psychological distress.

IPAQ (International Physical Activité Questionnaire) assesses overall physical activity and sedentary behavior over the past seven days. The short version with 7 questions will be used in this study. The minimum value is 0 Metabolic Equivalent of Task (MET) by week for sedentary people. The maximum value is at least 1500 MET by week for intensive active people. This questionnaire allows to assess people's activity and classifies participants into three activity levels: inactive, moderate, and high.

The Epworth Sleepiness Scale is a questionnaire designed to determine or measure daytime sleepiness across eight items. Subjects are asked to rate their frequency (or probability) of falling asleep on a scale of 0 to 3 in eight different situations commonly encountered in daily life. The eight items are summed to obtain a global score ranging from 0 to 24, with higher scores indicating greater sleepiness during common daily activities.

Heart rate (HR) in beats per minute will be recorded in a supine position in a quiet room after a 5-minute rest period.

Heart rate variability (HRV) will be recorded in a supine position in a quiet room after a 5-minute rest period with an electrocardiogram.

Blood pressure (BP) in millimeters of mercury will be recorded in a supine position in a quiet room after a 5-minute rest period with blood pressure monitor.