NCT01509456

Brief Summary

Mainly due to the absence of gravitational forces in weightlessness, astronauts suffer from an increased bone loss- negatively affecting health and vitality during a mission. The development of effective countermeasures to this loss includes many different aspects like sports but also nutrition. Alkaline salts, abundant in fruits and vegetables, have shown to have positive effects on markers of bone turnover of postmenopausal women but also men and younger adults. With the current study the effects of a potassium bicarbonate supplementation added to a standardised, strictly controlled, definite diet of healthy, young men, should be verified within 21 days of 6°- HDT- Bedrest- the gold standard of simulating weightlessness within earthbound conditions.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
8

participants targeted

Target at below P25 for not_applicable

Timeline
Completed

Started Feb 2010

Shorter than P25 for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

February 1, 2010

Completed
8 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

October 1, 2010

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

October 1, 2010

Completed
9 months until next milestone

First Submitted

Initial submission to the registry

July 4, 2011

Completed
6 months until next milestone

First Posted

Study publicly available on registry

January 13, 2012

Completed
Last Updated

March 1, 2017

Status Verified

February 1, 2017

Enrollment Period

8 months

First QC Date

July 4, 2011

Last Update Submit

February 28, 2017

Conditions

Bone Diseases, MetabolicAcid-Base ImbalanceMuscular AtrophySprains and StrainsProtein MetabolismBody Weight ChangesCardiovascular Abnormalities

Keywords

bone metabolismpotassium bicarbonatealkaline saltacid base balancebed rest

Outcome Measures

Primary Outcomes (1)

  • The reduction of the immobilisation induced bone loss by supplementing an alkaline salt (potassium bicarbonate)

    21 days of HDT- Bedrest

Secondary Outcomes (6)

  • Influence of KHCO3 on bone mass, bone mineral density and bone strength

    21 days of HDT- Bedrest

  • Determination of effects of KHCO3 on muscle strength, muscle power and muscle volume

    21 days of HDT- Bedrest

  • Determine the effects of KHCO3 on body composition and body weight

    21 days of HDT- Bedrest

  • Determine the effects of KHCO3 on the cardiovascular system

    21 days of HDT- Bedrest

  • Determine the effects of KHCO3 on the neuro- vestibular system

    21 days of HDT- Bedrest

  • +1 more secondary outcomes

Study Arms (2)

Potassium Bicarbonate

ACTIVE COMPARATOR
Dietary Supplement: Potassium Bicarbonate

Control

NO INTERVENTION

Interventions

Potassium BicarbonateDIETARY_SUPPLEMENT

90 mmol daily, effervescent tablets 30 mmol diluted in 200 ml tab water supplemented three times a day together with the main meals for 21 days of HDT- bedrest

Potassium Bicarbonate

Eligibility Criteria

Age20 Years - 45 Years
Sexmale
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • healthy male subjects
  • age: 20- 45
  • weight 65- 85 kg
  • height: 158- 190 cm
  • BMI 20- 26 kg/m2
  • no high performance sports
  • non- smoking (minimum 6 months prior to study start)
  • willing to complete both parts of the study
  • presentation of social security and criminal record
  • successful completion of medical and psychological screening
  • signed informed consent

You may not qualify if:

  • drugs- and alcohol abuse
  • antiinflammatory drugs taken during the study
  • vegetarianism, veganism
  • migraine
  • psychical illness in the past
  • claustrophobia
  • hiatal hernia
  • gastroesophageal reflux
  • diabetes mellitus
  • Rheumatic disease
  • muscle or joint disease
  • disc prolapse
  • orthostatic intolerance
  • Hyperlipidaemia
  • renal disease
  • +14 more criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

German Aerospace Centre (DLR)

Cologne, 51147, Germany

Location

Related Publications (1)

  • Frings-Meuthen P, Bernhardt G, Buehlmeier J, Baecker N, May F, Heer M. The negative effect of unloading exceeds the bone-sparing effect of alkaline supplementation: a bed rest study. Osteoporos Int. 2019 Feb;30(2):431-439. doi: 10.1007/s00198-018-4703-6. Epub 2018 Sep 25.

    PMID: 30255228DERIVED

MeSH Terms

Conditions

Bone Diseases, MetabolicAcid-Base ImbalanceMuscular AtrophySprains and StrainsBody Weight ChangesCardiovascular Abnormalities

Interventions

potassium bicarbonate

Condition Hierarchy (Ancestors)

Bone DiseasesMusculoskeletal DiseasesMetabolic DiseasesNutritional and Metabolic DiseasesNeuromuscular ManifestationsNeurologic ManifestationsNervous System DiseasesAtrophyPathological Conditions, AnatomicalPathological Conditions, Signs and SymptomsSigns and SymptomsWounds and InjuriesBody WeightCardiovascular DiseasesCongenital AbnormalitiesCongenital, Hereditary, and Neonatal Diseases and Abnormalities

Study Officials

  • Francisca May, Dr.

    German Aerospace Centre, Institute of Aerospace Medicine (DLR)

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
NONE
Purpose
BASIC SCIENCE
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

July 4, 2011

First Posted

January 13, 2012

Study Start

February 1, 2010

Primary Completion

October 1, 2010

Study Completion

October 1, 2010

Last Updated

March 1, 2017

Record last verified: 2017-02

Locations

DE(1)