Cocoa Intake and Muscle Pain Sensation

Study Overview
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Brief Summary
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This experimental randomized, double-blind, and controlled study included fifteen young, healthy, and pain-free men and 15 age-matched women. It lasted for three visits with at least one-week washout. Pain was experimentally induced, twice at each visit, with intramuscular injections of 0.2 mL hypertonic saline (5%), before and after intake of one of the different chocolate-types; white (30% cocoa-content), milk (34% cocoa-content), dark (70% cocoa-content). Pain duration, pain area, peak pain, and pressure pain threshold were assessed every fifth minute after each injection, between the time-points 5 to 30 min. Prior to inclusion, all participants underwent an examination in a dental chair. This included a clinical examination of the orofacial region according to the Diagnostic Criteria for temporomandibular disorders (DC/TMD) by a blinded examiner. Participants were also examined regarding their psychosocial status prior to inclusion, this included depression, somatization, anxiety, pain catastrophizing and stress.

Official Title
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Cocoa Intake and Muscle Pain Sensation: an Experimental Study

Conditions
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Muscle Pain

Intervention / Treatment
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* Other: before - hypertonic saline 5%
* Other: after - hypertonic saline 5%


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: good general health age between 18-40 years Exclusion Criteria: any pain-related diagnosis of TMD or of the orofacial region any headaches a diagnosis of systemic muscular or joint diseases (fibromyalgia or rheumatoid arthritis) whiplash-associated disorders neurological disorders psychiatric disorders any allergy to the substances used

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Dark Chocolate<br> | Other: before - hypertonic saline 5%<br>* pain was induced by intramuscular injections of hypertonic saline (5%)<br>Other: after - hypertonic saline 5%<br>* pain was induced by intramuscular injections of hypertonic saline (5%)<br>|
| Active Comparator: Milk Chocolate<br> | Other: before - hypertonic saline 5%<br>* pain was induced by intramuscular injections of hypertonic saline (5%)<br>Other: after - hypertonic saline 5%<br>* pain was induced by intramuscular injections of hypertonic saline (5%)<br>|
| Active Comparator: White Chocolate<br> | Other: before - hypertonic saline 5%<br>* pain was induced by intramuscular injections of hypertonic saline (5%)<br>Other: after - hypertonic saline 5%<br>* pain was induced by intramuscular injections of hypertonic saline (5%)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in pain intensity by intake of chocolate | Pain intensity will be assssed using a 0-100 visual analoge scale (0-no pain; 100-worst pain ever experienced) | 5 min after injection of hypertonic saline | 
| Change in peak pain intensity before and after intake of chocolate | Peak pain intensity will be asessed from the 0-100 visual analoge scale (0-no pain; 100-worst pain ever experienced) | 5 min after injection of hypertonic saline | 
| Change in pain duration by intake of chocolate | Pain duration is assessed in seconds. | Pain duration up to 300 seconds after injection of hypertonic saline | 
| Change in pain area by intake of chocolate | Pain area will be marked on lateral charts of the head before and after intake of chocolate and measured in au. | Pain area is marked 5 min after injection of hypertonic saline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in pressure pain threshold by intake of chocolate | Pressure pain thresholds are assessed using a digital algometer over the area of injection in the masseter muscle with a pressure rate of 30kPa/s. | Pressure pain thresholds are assessed 5 min after injection of hypertonic saline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Myalgia, Experimental pain, Human, Temporomandibular disorders, Cocoa