Marijuana Use, Strength Training, and Alcohol Consumption (MUSTAC) Study

Study Overview
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Brief Summary
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Self-medication of pain by consuming alcohol and marijuana is common. However, the research regarding pain as a determinant for alcohol and marijuana use has relied on laboratory pain induction paradigms with limited clinical relevance. The study will assess demand for alcohol and marijuana before and after delayed onset muscle soreness (DOMS) induction in co-users. This will provide a clinically relevant, but time-limited, model for the effects of musculoskeletal pain on demand.

Official Title
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Marijuana Use, Strength Training, and Alcohol Consumption (MUSTAC) Study

Conditions
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Chronic Pain

Intervention / Treatment
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* Behavioral: Eccentric Biceps Flexion
* Behavioral: Concentric Biceps Flexion


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 21 years; English-speaking Self-identify as White/Caucasian or Black/African American Own a smartphone with cellular/data plan Regularly co-use alcohol and smoked marijuana as indicated by scores of ≥3 on item 1 of the CUDIT-R and AUDIT. Willing and able to give informed consent Exclusion Criteria: Participation in biceps-specific conditioning program in the past 6 months* Self-reported wrist/hand, elbow, or shoulder pain the past 3 months Chronic medical condition that may affect pain perception (e.g. diabetes, fibromyalgia, headaches) Self-reported kidney dysfunction, muscle damage, or major psychiatric disorder Medical marijuana prescription Consumption of marijuana using only non-inhalational methods (e.g. edibles, tinctures, or cannabidiol oil) Score of ≥ 10 on Patient Health Questionnaire-9 (moderate depression) Women who are pregnant, trying to become pregnant, or breastfeeding

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 65 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Delayed Onset Muscle Soreness Induction<br>Participants will complete an exercise session designed to induce delayed onset muscle soreness in the biceps | Behavioral: Eccentric Biceps Flexion<br>* Muscle lengthening biceps exercise<br>|
| Sham Comparator: Sham Delayed Onset Muscle Soreness Induction<br>Participants will complete an exercise session that is unlikely to induce delayed onset muscle soreness in the biceps | Behavioral: Concentric Biceps Flexion<br>* Muscle shortening biceps exercise<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Alcohol Demand: Breakpoint | Changes in breakpoint of alcohol demand, assessed using the Alcohol Purchase Task. Breakpoint indicates the drink price at which participants report no alcohol consumption. Values represent difference scores derived from breakpoint values coded so that positive values indicate an increase in the demand index from baseline to follow-up. | 48 hours after exercise | 
| Alcohol Demand: Omax | Changes in Omax, assessed using the Alcohol Purchase Task. Omax reflects the highest total amount in dollars that a participant would spend on alcohol-containing beverages. Values represent difference scores derived from log-transformed Omax values coded so that positive values indicate an increase in the demand index from baseline to follow-up. | 48 hours after exercise | 
| Alcohol Demand: Pmax | Changes in Pmax, assessed using the Alcohol Purchase Task. Pmax reflects the price point at which demand for alcohol becomes elastic (i.e., declines in response to increasing price). Values represent difference scores derived from log-transformed Pmax values coded so that positive values indicate an increase in the demand index from baseline to follow-up. | 48 hours after exercise | 
| Alcohol Demand: Essential Value | Changes in Essential Value, assessed using the Alcohol Purchase Task. Essential Value represents the reinforcing efficacy of alcohol, such that higher Essential Value indicates greater reinforcing efficacy. Values represent difference scores derived from Essential Values coded so that positive numbers indicate an increase in the demand index from baseline to follow-up. | 48 hours after exercise | 
| Cannabis Demand: Intensity | Changes in intensity of cannabis demand, assessed using the Marijuana Purchase Task. Intensity reflects the number of joints that would hypothetically be consumed if they were free. Values represent difference scores derived from log-transformed intensity values coded so that positive values indicate an increase in the demand index from baseline to follow-up. | 48 hours after exercise | 
| Cannabis Demand: Breakpoint | Changes in breakpoint of cannabis demand, assessed using the Marijuana Purchase Task. Breakpoint indicates the joint price at which participants report no cannabis consumption. Values represent difference scores derived from breakpoint values coded so that positive values indicate an increase in the demand index from baseline to follow-up. | 48 hours after exercise | 
| Cannabis Demand: Omax | Changes in Omax, assessed using the Marijuana Purchase Task. Omax reflects the highest total amount that a participant would spend on cannabis. Values represent difference scores derived from log-transformed Omax values coded so that positive values indicate an increase in the demand index from baseline to follow-up. | 48 hours after exercise | 
| Cannabis Demand: Pmax | Changes in Pmax, assessed using the Marijuana Purchase Task. Pmax reflects the price point at which demand for cannabis becomes elastic (i.e., declines in response to increasing price). Values represent difference scores derived from log-transformed Pmax values coded so that positive values indicate an increase in the demand index from baseline to follow-up. | 48 hours after exercise | 
| Cannabis Demand: Essential Value | Changes in Essential Value, assessed using the Marijuana Purchase Task. Essential Value represents the reinforcing efficacy of cannabis, such that higher Essential Value indicates greater reinforcing efficacy. Values represent difference scores derived from Essential Values coded so that positive numbers indicate an increase in the demand index from baseline to follow-up. | 48 hours after exercise | 
| Alcohol Demand: Intensity | Changes in intensity of alcohol demand, assessed using the Alcohol Purchase Task. Intensity reflects the number of drinks that would hypothetically be consumed if they were free. Values represent difference scores derived from log-transformed number of drinks coded so that positive values indicate an increase in the demand index from baseline to follow-up. | 48 hours after exercise |