Pain sensitivity after low-level clenching is influenced by preloading eccentric exercise

Area of Science:

• Neurology
• Pain Research
• Exercise Physiology

Background:

• Understanding factors influencing pain sensitivity is crucial for managing chronic pain conditions.
• Jaw clenching (bruxism) can lead to significant pain and discomfort.
• The role of preconditioning exercise on subsequent pain perception requires further investigation.

Purpose of the Study:

• To investigate the impact of preloading eccentric exercise on pain sensitivity in healthy volunteers.
• To compare the effects of eccentric exercise versus gum chewing as preloading stimuli.

Main Methods:

• Twenty healthy volunteers participated in the study.
• Pain sensitivity was assessed using a visual analog scale (VAS) after electrical stimuli on the masseter and hand.
• Preloading involved 6 minutes of either eccentric exercise or gum chewing, followed by 15 minutes of low-level clenching two days later.

Main Results:

• Eccentric exercise resulted in low levels of pain-related sensations two days post-exercise.
• Temporal summation of pain in the masseter muscle increased after low-level clenching when preceded by eccentric exercise (P=0.016).
• No significant changes in temporal summation were observed when preloading involved gum chewing.

Conclusions:

• Eccentric exercise may enhance central nervous system pain sensitivity, facilitating pain from subsequent jaw clenching.
• The type of preloading exercise significantly influences pain sensitivity following low-level clenching.
• Eccentric exercise could be a contributing factor in the development of chronic tooth clenching-related pain.