Light, Exercise Intensity and Mood in Overweight

Study Overview
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Brief Summary
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The purpose of this study is to determine if an exposure to light in the morning has a positive influence on self-chosen exercise intensity on a bicycle ergometer in overweight and obese patients.

Official Title
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Light, Exercise Intensity and Mood in Overweight

Conditions
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Overweight, Obesity Grade I

Intervention / Treatment
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* Device: Phillips Energy Light HF3319


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Body Mass Index 25 - 35 kg/m2 Exclusion Criteria: Women who are pregnant or breast feeding, Other clinically significant concomitant disease states (e.g., renal failure, hepatic dysfunction, cardiovascular disease, etc.), Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, dementia, etc. of the participant Previous enrolment into the current study Participation in other studies in the last four weeks Systolic blood pressure > 170 mmHg, diastolic blood pressure > 100 mmHg Shift work in the last two months Travels across time zones in the last four weeks Use of photosensitisation drugs Clinical manifest depression Cardiovascular diseases which reduce age-appropriate exercise capacity

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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Bright Light<br>8 a.m. study participants will be exposed to Bright Light (4500 lx) Phillips Energy Light HF3319 for 30 minutes prior and during a 30 minute lasting exercise test with self-chosen exercise intensity on a bicycle ergometer. The light exposure and time-trial will be performed in three repetitive exercise sessions 48h apart. | Device: Phillips Energy Light HF3319<br>* Exposure to Light administered with Phillips Energy Light HF3319.<br>|
| Experimental: Control<br>8 a.m. study participants will be exposed to a Control Light Condition (230 lx) Phillips Energy Light HF3319 for 30 minutes prior and during a 30 minute lasting exercise test with self-chosen exercise intensity on a bicycle ergometer. The light exposure and time-trial will be performed in three repetitive exercise sessions 48h apart. | Device: Phillips Energy Light HF3319<br>* Exposure to Light administered with Phillips Energy Light HF3319.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean power output in watts |  | Power output during the first 30 minute time-trial on a bicycle ergometer. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Subjective sleepiness | Subjective sleepiness will be measured with the Multidimensional Mood Questionnaire (Category Wakefulness - Sleepiness) | 1 minute after the light exposure vs. 1 minute before the light exposure in the first time trial | 
| Subjective Mood | Subjective Mood measured with the Multidimensional Mood Questionnaire (Category Good Mood - Bad Mood) | 1 minute after the light exposure vs. 1 minute before the light exposure in the first time trial | 
| Mean power output in watts during the first, second and third time-trial on a bicycle ergometer. |  | Mean of the 30 minutes of the exercise from the first, second and third time-trial. |