## Protocol Section
### Identification Module
**NCT ID:** NCT01655979

**Acronym:** MEP

**Brief Title:** Medium-term Bedrest Whey Protein (MEP)

#### Organization Study ID Info
**ID:** ESA-AO-06-BR
#### Organization
**Class:** OTHER
**Full Name:** DLR German Aerospace Center
### Status Module
#### Expanded Access Info
#### Last Update Post Date
**Date:** 2012-08-02

**Type:** ESTIMATED

**Last Update Submit Date:** 2012-07-31

**Overall Status:** COMPLETED

#### Primary Completion Date
**Date:** 2012-04

**Type:** ACTUAL

#### Start Date
**Date:** 2011-08

**Status Verified Date:** 2012-07

#### Study First Post Date
**Date:** 2012-08-02
**Type:** ESTIMATED
**Study First Submit Date:** 2012-07-23
**Study First Submit QC Date:** 2012-07-31
### Sponsor Collaborators Module

#### Collaborators

**Class:** OTHER

**Name:** European Space Agency

**Class:** OTHER

**Name:** University Hospital, Clermont-Ferrand

**Class:** UNKNOWN

**Name:** Institut Pluridisciplinaire Hubert Curien, Strasbourg, France

**Class:** OTHER

**Name:** Charite University, Berlin, Germany

**Class:** OTHER

**Name:** University of Milan

**Class:** OTHER

**Name:** Université de Nice Sophia Antipolis

**Class:** OTHER

**Name:** University of Ottawa

**Class:** OTHER

**Name:** Manchester Metropolitan University

**Class:** OTHER

**Name:** University of Toronto

**Class:** OTHER

**Name:** Medical University of Graz

**Class:** OTHER

**Name:** University of Cologne

**Class:** OTHER

**Name:** Radboud University Medical Center

**Class:** OTHER

**Name:** University Hospital, Lille

**Class:** OTHER

**Name:** Leiden University Medical Center

#### Lead Sponsor

**Class:** OTHER

**Name:** DLR German Aerospace Center

#### Responsible Party

**Type:** SPONSOR

### Description Module

**Brief Summary:** The human being has shown that he can live and work in the space environment, but due to the lack of essential mechanical load on muscle and bone, the fluid-shift as well as alterations in the acid-base balance (mainly on account of nutritional factors), the exposure to microgravity results in a gradual degradation of muscle, bone and cartilage, deconditioning of the cardiovascular system and metabolic changes. Countermeasures to prevent all the deconditioning of the physiological systems are not yet fully effective and require further investigation.

A commonly utilized model of simulating the physiological effects of microgravity on the human organism on ground is the 6° head-down-tilt bed rest. In the present study the model has been used to study potential countermeasures to spaceflight-associated deconditioning.

One of the most constrictive changes appearing during space flight as well as during bed rest, are disuse-induced muscle losses. These are associated with a decrease in muscle protein synthesis, rather then an increase in muscle protein breakdown. Besides an effective training countermeasure, nutritional countermeasures gain respect in this context: supplementing conventional diets with whey protein or essential amino acids has been shown to increase muscle protein synthesis. Due to these anabolic properties whey protein seems promising to counteract disuse-induced muscle wasting.

Drawbacks of a high protein intake are calciuric effects, ascribed to the proton-release when metabolizing sulfur-containing amino acids. The so called 'low grade metabolic acidosis' has also shown to activate osteoclastic bone resorption and muscle protein degradation. Therefore, to maximize the anabolic potential of a whey protein supplementation, the acidogenic properties need to be compensated. As previous works suggest, a shift of acid base balance into the acid direction and the resulting changes in bone and protein turnover may be hindered by supplementing alkaline mineral salts.

In this regard, a mid-term bed rest study was performed in order to investigate the effect of a combined whey protein (0.6 g/kg body weight/day) and potassium bicarbonate (90 mmol/day) supplementation as a potential countermeasure to multiple physiological and metabolic alterations on the human body resulting from real and simulated microgravity.

### Conditions Module

**Conditions:**

- Countermeasure Evaluation

### Design Module

#### Design Info

**Allocation:** RANDOMIZED

**Intervention Model:** CROSSOVER

##### Masking Info

**Masking:** NONE

**Primary Purpose:** TREATMENT

#### Enrollment Info

**Count:** 10

**Type:** ACTUAL

**Phases:**

- NA

**Study Type:** INTERVENTIONAL

### Arms Interventions Module

#### Arm Group 1

**Intervention Names:**

- Dietary Supplement: Whey Protein + Potassium bicarbonate

- Other: Control

**Label:** MEP-1

**Type:** EXPERIMENTAL

#### Arm Group 2

**Intervention Names:**

- Dietary Supplement: Whey Protein + Potassium bicarbonate

- Other: Control

**Label:** MEP-2

**Type:** EXPERIMENTAL

### Interventions

#### Intervention 1

**Arm Group Labels:**

- MEP-1

- MEP-2

**Description:** 0.6 mmol WP/kg body weight + 90 mmol KHCO3 during bed rest

**Name:** Whey Protein + Potassium bicarbonate

**Type:** DIETARY_SUPPLEMENT

#### Intervention 2

**Arm Group Labels:**

- MEP-1

- MEP-2

**Description:** Bed rest without dietary supplement

**Name:** Control

**Type:** OTHER

### Outcomes Module

#### Primary Outcomes

**Measure:** Change in body composition

**Time Frame:** Baseline, after 21 days of bed rest

#### Secondary Outcomes

**Measure:** Plasma Volume

**Time Frame:** Baseline, after 21 days of bed rest

**Measure:** Maximum volume of oxygen uptake

**Time Frame:** Baseline, after 21 days of bed rest

**Description:** During a an Isometric Maximum Voluntary Contraction Test on the knee extensors \& flexors, the plantarflexors and dorsiflexors, the elbow extensors \& flexors the Isometric Torque will be measured in Nm.

**Measure:** Isometric torque

**Time Frame:** Baseline, after 21 days of bed rest

**Measure:** Muscle fatigue

**Time Frame:** Baseline, after 21 days of bed rest

**Measure:** Bone metabolism

**Time Frame:** Baseline, after 2,5,14,21 days of bed rest, 1, 5, 14, 28 days after finishing bed rest

**Measure:** Bone mineral density + content

**Time Frame:** Baseline, after 21 days of bed rest

**Measure:** Standing balance

**Time Frame:** Baseline, after 21 days of bed rest

**Description:** Locomotion will be assessed by Dynamic Gait Index, specific parameters are: total Score and Subscore

**Measure:** Locomotion

**Time Frame:** Baseline, after 21 days of bed rest

**Measure:** Body mass

**Time Frame:** Daily for a duration of 35 days

**Measure:** Intracranial pressure

**Time Frame:** Baseline, after 1,4, 7,10,13,14,15,16,17,18,19,20,21 days of bed rest,1,2,4 days after finishing bed rest

**Measure:** Monitoring of Vitamin K status

**Time Frame:** Baseline, after 2,5,14,21 days of bed rest, 1, 5 days after finishing bed rest

**Measure:** Fat metabolism

**Time Frame:** Baseline, after 21 days of bed rest

**Measure:** Glucose metabolism

**Time Frame:** Baseline, after 21 days of bed rest, 4 days after finishing bed rest

**Measure:** Nitrogen balance

**Time Frame:** Daily for a duration of 33 days

**Measure:** Energy metabolism

**Time Frame:** Baseline, after 21 days of bed rest

**Measure:** Glucocorticoid activity

**Time Frame:** Baseline, after 2,3,7,8,12,13,16,17 days of bed rest, 2,3 days after finishing bed rest

**Measure:** Muscle metabolism

**Time Frame:** Baseline, after 21 days of bed rest

**Measure:** Acid base balance

**Time Frame:** Baseline, after 2, 14, 21 days of bed rest, 5 days after finishing bed rest

**Description:** Muscle sympathetic nerve activity is measured by MSNA recording by microneurography technique.

**Measure:** Sympathetic activity during orthostatic stress

**Time Frame:** Baseline, after 21 days of bed rest

**Description:** Visual Orientation is assessed by 'Oriented Character Recognition Test' and Luminous Line Test. The main parameter is Score.

**Measure:** Visual Orientation

**Time Frame:** Baseline, after 6,12,20 days of bed rest, 2,4 days after finishing bed rest

**Measure:** Plasma galanin and adrenomedullin responses during head up tilt test (orthostatic stress)

**Time Frame:** Baseline, after 21 days of bed rest

**Measure:** Cartilage metabolism and -thickness

**Time Frame:** Baseline, after 2,3,5,7,14,21 days of bed rest, 5 days after finishing bed rest

**Description:** Blood cell count, reticulocytes, Haptoglobin, Bilirubin, Ferritin, EPO, Thrombopoietin, Urinary Urobilinogen and Fecal Urobilinogen (markers of blood cell degradation)

**Measure:** Hematopoetic system

**Time Frame:** Baseline, after 10, 21 days of bed rest, 1, 28 days after finishing bed rest

**Measure:** Fat accumulation in bone marrow

**Time Frame:** Baseline, after 10, 21 days of bed rest, 3, 28 days after finishing bed rest

**Measure:** Achilles tendon structure

**Time Frame:** Baseline, after 21 days of bed rest, 2, 28 days after finishing bed rest

**Measure:** Headache - frequency and quality

**Time Frame:** Baseline, daily during 21 days of bed rest

**Measure:** Muscle volume

**Time Frame:** Baseline, after 20, 21 days of bed rest, 3 days after finishing bed rest

**Measure:** Free water and fat content in muscle

**Time Frame:** Baseline, after 20, 21 days of bed rest, 3 days after finishing bed rest

**Description:** Orthostatic tolerance will be assessed by Head up tilt test. The following parameters are assessed to measure orthostatic tolerance: beat-to-beat heart rate \[bpm\], beat-to-beat blood pressure \[bpm\] time to presyncope \[min, s\]

**Measure:** Orthostatic tolerance

**Time Frame:** Baseline, after 21 days of bed rest

### Eligibility Module

**Eligibility Criteria:** Inclusion Criteria:

* Healthy males, 20 -45 years
* BMI: 20 - 25 kg/m2
* Height: 158 - 190 cm
* Weight: 65 - 85 kg
* maximum relative oxygen uptake: 30 - 60 ml/min/kg
* non-smokers
* successful medical and psychological screening
* Willingness to participate in the entire study
* signed informed consent
* social insurance
* Clear criminal background check

Exclusion Criteria:

* Abuse of drugs, medicine or alcohol
* Vegetarians, Vegans
* Migraines
* History of mental illness
* Claustrophobia
* History of: thyroid dysfunction, renal stones, diabetes, allergies, hypertension, hypocalcaemia, uric acidaemia, lipidaemia, hyperhomocysteinaemia
* Rheumatism
* Muscle-, Cartilage- or Joint Injuries
* Gastro-esophageal reflux disease, renal function disorder, Hiatus hernia
* Chronic back pain
* Bone diseases
* Herniated discs
* Achilles tendon injuries
* Cruciate ligament rupture or any other severe knee injury
* BMD more than 1.5 SD \< t-score
* History of orthostatic intolerance or vestibular disorders
* Anaemia
* Vitamin D Deficiency
* Positive response in thrombosis screening
* Use of metallic implants, osteosynthesis material
* Porphyria, Blood dyscrasia
* HIV, Hepatitis
* Increased Inner Eye pressure
* Intolerance to local anesthetics
* Participation in another study up to three month before study onset

**Healthy Volunteers:** True

**Maximum Age:** 45 Years

**Minimum Age:** 20 Years

**Sex:** MALE

**Standard Ages:**

- ADULT

### Contacts Locations Module

#### Locations

**Location 1:**

**City:** Cologne

**Country:** Germany

**Facility:** DLR German Aerospace Center

**Zip:** 51147

### References Module

#### References

**Citation:** Rudwill F, O'Gorman D, Lefai E, Chery I, Zahariev A, Normand S, Pagano AF, Chopard A, Damiot A, Laurens C, Hodson L, Canet-Soulas E, Heer M, Meuthen PF, Buehlmeier J, Baecker N, Meiller L, Gauquelin-Koch G, Blanc S, Simon C, Bergouignan A. Metabolic Inflexibility Is an Early Marker of Bed-Rest-Induced Glucose Intolerance Even When Fat Mass Is Stable. J Clin Endocrinol Metab. 2018 May 1;103(5):1910-1920. doi: 10.1210/jc.2017-02267.

**PMID:** 29546280

## Derived Section

### Intervention Browse Module - Browse Branches

- Abbrev: Ot

- Name: Other Dietary Supplements

- Abbrev: All

- Name: All Drugs and Chemicals

### Intervention Browse Module - Browse Leaves

- ID: T435

- Name: Whey Protein

- Relevance: HIGH

- As Found: Ingredients

### Misc Info Module

- Version Holder: 2024-05-24
