<clinical_study>
  <!-- This xml conforms to an XML Schema at:
    https://clinicaltrials.gov/ct2/html/images/info/public.xsd -->
  <required_header>
    <download_date>ClinicalTrials.gov processed this data on September 20, 2023</download_date>
    <link_text>Link to the current ClinicalTrials.gov record.</link_text>
    <url>https://clinicaltrials.gov/ct2/show/NCT03293901</url>
  </required_header>
  <id_info>
    <org_study_id>17-13-HC</org_study_id>
    <nct_id>NCT03293901</nct_id>
  </id_info>
  <brief_title>Calcium Kinetic Responses to Exercise</brief_title>
  <official_title>Skeletal Hormone and Calcium Kinetic Responses to Load Carriage Exercise in Females</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>United States Army Research Institute of Environmental Medicine</agency>
      <agency_class>U.S. Fed</agency_class>
    </lead_sponsor>
    <collaborator>
      <agency>Cornell University</agency>
      <agency_class>Other</agency_class>
    </collaborator>
  </sponsors>
  <source>United States Army Research Institute of Environmental Medicine</source>
  <oversight_info>
    <is_fda_regulated_drug>No</is_fda_regulated_drug>
    <is_fda_regulated_device>No</is_fda_regulated_device>
  </oversight_info>
  <brief_summary>
    <textblock>
      This randomized cross-over study will identify physiological factors that underlie changes in&#xD;
      bone metabolism that could affect skeletal injury risk, to include increases in parathyroid&#xD;
      hormone (PTH) in response to militarily relevant exercise in females. The primary objective&#xD;
      is to determine the hormone and calcium (Ca) response to multiple bouts of load carriage&#xD;
      exercise in females. The investigators hypothesize that PTH will increase after multiple&#xD;
      bouts of load carriage exercise and this increase will be due to disruption in Ca kinetics,&#xD;
      specifically either a decrease in fractional intestinal Ca absorption (FCA) or changes in&#xD;
      bone formation and/or resorption.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      Initial military training (IMT) results in increased risk of stress fracture, particularly&#xD;
      for females as up to 21% of females may sustain a stress fracture during IMT, an incidence&#xD;
      that is approximately 4-fold higher than that for males. Young female adults will undergo two&#xD;
      separate study periods in random order, one will include exercise and the other will not.&#xD;
      Each study period will use dual stable Ca isotope methodology in order to determine Ca&#xD;
      kinetic responses to a militarily relevant exercise, and dietary intake will be controlled.&#xD;
      Kinetic analyses will include fractional intestinal Ca absorption (FCA), Ca flux into bone&#xD;
      (Vo+) and out of bone (Vo-), as well as renal Ca handling. Serial blood samples collected&#xD;
      during the study periods will also be used to determine hormonal responses to exercise. The&#xD;
      treadmill exercise will consist of a 60 minute timed trial with load carriage (30% body&#xD;
      weight) completed three times during the 6 day kinetic period. At the start of the study,&#xD;
      blood will be collected for analysis of Ca and bone-related genetic markers, and habitual&#xD;
      food intake and exercise will be assessed. The information gathered from this trial will be&#xD;
      used to identify physiological responses that can be targeted by future interventions&#xD;
      designed to improve bone responses to training and decrease injury risk in female Warriors.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Completed</overall_status>
  <start_date type="Actual">June 16, 2018</start_date>
  <completion_date type="Actual">March 18, 2020</completion_date>
  <primary_completion_date type="Actual">March 18, 2020</primary_completion_date>
  <phase>N/A</phase>
  <study_type>Interventional</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <allocation>Randomized</allocation>
    <intervention_model>Crossover Assignment</intervention_model>
    <primary_purpose>Basic Science</primary_purpose>
    <masking>None (Open Label)</masking>
  </study_design_info>
  <primary_outcome>
    <measure>Hormone response and calcium kinetics</measure>
    <time_frame>Exercise or rest will occur on days 0, 2, and 4 and measures will be taken daily days 0-4. After a washout period, measures will be repeated 1-4 weeks later on days 0, 2, and 4 with whichever intervention was not performed during the first study period.</time_frame>
    <description>After dosing with dual stable calcium isotopes, changes in calcium kinetics (isotopic rations) will be measured in response to multiple bouts of a militarily relevant load carriage exercise or no exercise (rest) in females.</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Fractional calcium absorption</measure>
    <time_frame>Bone measurement will be taken at baseline and FCA will be measured once during each intervention (exercise or rest) on day 0.</time_frame>
    <description>Determine whether fractional Ca absorption (FCA) is associated with bone microarchitecture and strength in females undergoing multiple bouts of a militarily relevant load carriage exercise</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Single nucleotide polymorphisms</measure>
    <time_frame>SNP measurement will be taken at baseline and calcium measurements will be taken daily on days 0-4 when undergoing exercise and daily on days 0-4 when there is no exercise (rest).</time_frame>
    <description>Evaluate whether single nucleotide polymorphisms (SNPs) previously identified to be associated with circulating 25OHD concentrations explain some of the variability in calcium kinetic responses to load carriage exercise.</description>
  </secondary_outcome>
  <number_of_arms>2</number_of_arms>
  <enrollment type="Actual">21</enrollment>
  <condition>Nutritional Status</condition>
  <condition>Bones</condition>
  <arm_group>
    <arm_group_label>Rest</arm_group_label>
    <arm_group_type>No Intervention</arm_group_type>
  </arm_group>
  <arm_group>
    <arm_group_label>Exercise</arm_group_label>
    <arm_group_type>Active Comparator</arm_group_type>
    <description>Militarily relevant exercise</description>
  </arm_group>
  <intervention>
    <intervention_type>Behavioral</intervention_type>
    <intervention_name>Exercise</intervention_name>
    <description>Treadmill exercise for 60 minutes with load carriage (weighted vest, 30% body weight) completed three times during the 6 day kinetic period.</description>
    <arm_group_label>Exercise</arm_group_label>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  Women aged 18-42 years&#xD;
&#xD;
          -  No current or prior military service&#xD;
&#xD;
          -  Exercise 2-5 x/wk&#xD;
&#xD;
          -  Stable body weight for 2 months (±5 lbs)&#xD;
&#xD;
          -  Body mass index (BMI) between 19-26 kg/m2&#xD;
&#xD;
          -  VO2max between 35-50 ml·kg-1·min-1&#xD;
&#xD;
          -  Willing to discontinue use of dietary supplements and abstain from alcohol for the&#xD;
             duration of the study&#xD;
&#xD;
          -  Have not donated blood within the last 8 weeks&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  History of endocrine disorders (e.g., diabetes, uncontrolled thyroid dysfunction,&#xD;
             hypoparathyroidism, or hyperparathyroidism)&#xD;
&#xD;
          -  History of bone-modifying disorders (e.g., osteogenesis imperfecta, osteopetrosis, or&#xD;
             rickets)&#xD;
&#xD;
          -  History of cardiovascular or renal disease&#xD;
&#xD;
          -  Pregnancy or lactation in the last 6 months&#xD;
&#xD;
          -  Routine use of medications known to affect bone or calcium metabolism (e.g., thiazide&#xD;
             diuretics, bisphosphonates, oral steroids)&#xD;
&#xD;
          -  A very restrictive diet or severe food allergies&#xD;
      </textblock>
    </criteria>
    <gender>Female</gender>
    <gender_based>Yes</gender_based>
    <gender_description>Eligibility based on female anatomical sex characteristics</gender_description>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>42 Years</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Erin Gaffney-Stomberg, PhD, RD</last_name>
    <role>Principal Investigator</role>
    <affiliation>United States Research Institute of Environmental Medicine</affiliation>
  </overall_official>
  <location>
    <facility>
      <name>United States Army Research Institute of Environmental Medicine</name>
      <address>
        <city>Natick</city>
        <state>Massachusetts</state>
        <zip>01760</zip>
        <country>United States</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>United States</country>
  </location_countries>
  <verification_date>December 2022</verification_date>
  <study_first_submitted>August 10, 2017</study_first_submitted>
  <study_first_submitted_qc>September 20, 2017</study_first_submitted_qc>
  <study_first_posted type="Actual">September 26, 2017</study_first_posted>
  <last_update_submitted>December 20, 2022</last_update_submitted>
  <last_update_submitted_qc>December 20, 2022</last_update_submitted_qc>
  <last_update_posted type="Actual">December 21, 2022</last_update_posted>
  <responsible_party>
    <responsible_party_type>Sponsor</responsible_party_type>
  </responsible_party>
  <!-- Results have not yet been posted for this study                                          -->
</clinical_study>


download date: ClinicalTrials.gov processed this data on September 20, 2023
link text: Link to the current ClinicalTrials.gov record.
url: https://clinicaltrials.gov/ct2/show/NCT03293901
org study id: 17-13-HC
nct id: NCT03293901
lead sponsor: 
collaborator: 
is fda regulated drug: No
is fda regulated device: No
This randomized cross-over study will identify physiological factors that underlie changes in
      bone metabolism that could affect skeletal injury risk, to include increases in parathyroid
      hormone (PTH) in response to militarily relevant exercise in females. The primary objective
      is to determine the hormone and calcium (Ca) response to multiple bouts of load carriage
      exercise in females. The investigators hypothesize that PTH will increase after multiple
      bouts of load carriage exercise and this increase will be due to disruption in Ca kinetics,
      specifically either a decrease in fractional intestinal Ca absorption (FCA) or changes in
      bone formation and/or resorption.
Initial military training (IMT) results in increased risk of stress fracture, particularly
      for females as up to 21% of females may sustain a stress fracture during IMT, an incidence
      that is approximately 4-fold higher than that for males. Young female adults will undergo two
      separate study periods in random order, one will include exercise and the other will not.
      Each study period will use dual stable Ca isotope methodology in order to determine Ca
      kinetic responses to a militarily relevant exercise, and dietary intake will be controlled.
      Kinetic analyses will include fractional intestinal Ca absorption (FCA), Ca flux into bone
      (Vo+) and out of bone (Vo-), as well as renal Ca handling. Serial blood samples collected
      during the study periods will also be used to determine hormonal responses to exercise. The
      treadmill exercise will consist of a 60 minute timed trial with load carriage (30% body
      weight) completed three times during the 6 day kinetic period. At the start of the study,
      blood will be collected for analysis of Ca and bone-related genetic markers, and habitual
      food intake and exercise will be assessed. The information gathered from this trial will be
      used to identify physiological responses that can be targeted by future interventions
      designed to improve bone responses to training and decrease injury risk in female Warriors.
allocation: Randomized
intervention model: Crossover Assignment
primary purpose: Basic Science
masking: None (Open Label)
measure: Hormone response and calcium kinetics
time frame: Exercise or rest will occur on days 0, 2, and 4 and measures will be taken daily days 0-4. After a washout period, measures will be repeated 1-4 weeks later on days 0, 2, and 4 with whichever intervention was not performed during the first study period.
description: After dosing with dual stable calcium isotopes, changes in calcium kinetics (isotopic rations) will be measured in response to multiple bouts of a militarily relevant load carriage exercise or no exercise (rest) in females.
measure: Fractional calcium absorption
time frame: Bone measurement will be taken at baseline and FCA will be measured once during each intervention (exercise or rest) on day 0.
description: Determine whether fractional Ca absorption (FCA) is associated with bone microarchitecture and strength in females undergoing multiple bouts of a militarily relevant load carriage exercise
measure: Single nucleotide polymorphisms
time frame: SNP measurement will be taken at baseline and calcium measurements will be taken daily on days 0-4 when undergoing exercise and daily on days 0-4 when there is no exercise (rest).
description: Evaluate whether single nucleotide polymorphisms (SNPs) previously identified to be associated with circulating 25OHD concentrations explain some of the variability in calcium kinetic responses to load carriage exercise.
arm group label: Rest
arm group type: No Intervention
arm group label: Exercise
arm group type: Active Comparator
description: Militarily relevant exercise
intervention type: Behavioral
intervention name: Exercise
description: Treadmill exercise for 60 minutes with load carriage (weighted vest, 30% body weight) completed three times during the 6 day kinetic period.
arm group label: Exercise
criteria: 
gender: Female
gender based: Yes
gender description: Eligibility based on female anatomical sex characteristics
minimum age: 18 Years
maximum age: 42 Years
healthy volunteers: Accepts Healthy Volunteers
last name: Erin Gaffney-Stomberg, PhD, RD
role: Principal Investigator
affiliation: United States Research Institute of Environmental Medicine
facility: 
country: United States
responsible party type: Sponsor