Medium-term Bedrest Whey Protein (MEP)

NCT01655979 | Completed

• 1 other identifier: ESA-AO-06-BR
• Study Type: interventional
• Target: 10
• Locations: 1 country
• Sites: 1

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

Countermeasure Evaluation

Outcome Measures

Primary Outcomes (1)

• Change in body composition

  Baseline, after 21 days of bed rest

Secondary Outcomes (29)

• Plasma Volume

  Baseline, after 21 days of bed rest

• Maximum volume of oxygen uptake

  Baseline, after 21 days of bed rest

• Isometric torque

  Baseline, after 21 days of bed rest

• Muscle fatigue

  Baseline, after 21 days of bed rest

• Bone metabolism

  Baseline, after 2,5,14,21 days of bed rest, 1, 5, 14, 28 days after finishing bed rest

Study Arms (2)

MEP-1

EXPERIMENTAL

Dietary Supplement: Whey Protein + Potassium bicarbonate; Other: Control

MEP-2

EXPERIMENTAL

Dietary Supplement: Whey Protein + Potassium bicarbonate; Other: Control

Interventions

Whey Protein + Potassium bicarbonate DIETARY_SUPPLEMENT

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

MEP-1; MEP-2

Control OTHER

Bed rest without dietary supplement

MEP-1; MEP-2

Eligibility Criteria

• Age: 20 Years - 45 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• 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

You may not qualify if:

• 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

Sponsors & Collaborators

• DLR German Aerospace Center: lead
• European Space Agency: collaborator
• University Hospital, Clermont-Ferrand: collaborator
• Institut Pluridisciplinaire Hubert Curien, Strasbourg, France: collaborator
• Charite University, Berlin, Germany: collaborator
• University of Milan: collaborator
• Université de Nice Sophia Antipolis: collaborator
• University of Ottawa: collaborator
• Manchester Metropolitan University: collaborator
• University of Toronto: collaborator
• Medical University of Graz: collaborator
• University of Cologne: collaborator
• Radboud University Medical Center: collaborator
• University Hospital, Lille: collaborator
• Leiden University Medical Center: collaborator

Study Sites (1)

DLR German Aerospace Center

Cologne, 51147, Germany

Location

Related Publications (1)

• 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

MeSH Terms

Interventions

Whey Proteins; potassium bicarbonate

Intervention Hierarchy (Ancestors)

Milk Proteins; Animal Proteins, Dietary; Dietary Proteins; Proteins; Amino Acids, Peptides, and Proteins; Whey; Milk; Dairy Products; Food; Diet, Food, and Nutrition; Physiological Phenomena; Food and Beverages

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 23, 2012
• First Posted: August 2, 2012
• Study Start: August 1, 2011
• Primary Completion: April 1, 2012
• Last Updated: August 2, 2012

Record last verified: 2012-07

Locations

DE (1)