Influence of Graded Hypercapnia on Endurance Exercise Performance

NCT05116397 | Completed

• 1 other identifier: USARIEM
• Study Type: interventional
• Target: 15
• Locations: 1 country
• Sites: 1

Brief Summary

The aim of this randomized, single-blind, placebo-controlled crossover trial is to determine the effects of graded hypercapnia (0, 2, and 4% inspired CO2) on endurance performance. Twelve healthy and fit young adults (men and women) will complete this study. Participants will perform experimental trials on 3 separate days (one each breathing 0%, 2%, and 4% inspired CO2-all with normal 21% oxygen). During each trial, they will perform 10 minutes of submaximal treadmill walking exercise and then complete a self-paced 2-mile treadmill run time-trial.

Conditions

Hypercapnia

Outcome Measures

Primary Outcomes (1)

• 2 mile self-paced treadmill time trial performance

  Time to complete self-paced 2 mile treadmill time trial (min:sec)

  30 minutes

Secondary Outcomes (11)

• Ventilation rate

  30 minutes

• Oxygen consumption

  30 minutes

• Heart rate

  30 minutes

• Arterialized capillary pH

  30 minutes

• Arterialized capillary pCO2

  30 minutes

Study Arms (3)

4% CO2

EXPERIMENTAL

Inspired gas containing 4% CO2, 21% O2, balance N2

Other: Inspired gas

2% CO2

EXPERIMENTAL

Inspired gas containing 2% CO2, 21% O2, balance N2

Other: Inspired gas

0% CO2

SHAM COMPARATOR

Inspired gas containing 0% CO2, 21% O2, balance N2

Other: Inspired gas

Interventions

Inspired gas OTHER

Inspired gas content

0% CO2; 2% CO2; 4% CO2

Eligibility Criteria

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

You may qualify if:

• Male or female, age 18-45
• In good health as determined by medical screening
• Passed his/her most recent Army Combat Fitness Test (ACFT) (Military Volunteers Only) or performs aerobic exercise at least 2 times per week and able to complete two mile run in ≤ 21 minutes (Civilian Volunteers)
• Willing to not participate in any exercise or drink alcoholic beverages for 24 hours before each study visit.
• Willing to not take part in any strenuous exercise in the 36 hours before each visit.
• Willing not to drink caffeine or eat food until after testing on familiarization and performance testing visits (visits 2-6).
• Willing to maintain a similar dietary pattern in the 2 days before each familiarization and performance visits.
• Have supervisor approval if permanent party military or a federal employee at U.S. Army Natick Soldier System Center
• Able to speak and read English fluently

You may not qualify if:

• Females who are pregnant or planning to become pregnant during the study
• Taking dietary supplements, prescriptions, or over the counter medication, other than a contraceptive (unless approved by medical staff \& PI)
• Musculoskeletal injuries that compromise ability to run on a treadmill
• Abnormal blood count, presence of abnormal blood chemicals (hemoglobin S or sickle cell traits)
• Smokers or tobacco/nicotine users (unless have quit \> 1 month prior)
• Any history of asthma
• Current or recent respiratory tract or sinus infections (\< 1 month prior)
• Allergy to skin adhesive
• Any history of migraine or recurrent headaches
• Any history of panic disorder
• Blood donation in the previous 8 weeks
• Positive Covid-19 test within the last month

Sponsors & Collaborators

• United States Army Research Institute of Environmental Medicine: lead

Study Sites (1)

USARIEM

Natick, Massachusetts, 01760, United States

Location

MeSH Terms

Conditions

Hypercapnia

Condition Hierarchy (Ancestors)

Signs and Symptoms, Respiratory; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Benjamin J Ryan, Ph.D.

  United States Army Research Institute of Environmental Medicine

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Masking Details: Single-blinded
• Purpose: OTHER
• Intervention Model: CROSSOVER
• Sponsor Type: FED
• Responsible Party: SPONSOR

Model Details: Randomized, single-blinded crossover design

Study Record Dates

• First Submitted: October 13, 2021
• First Posted: November 11, 2021
• Study Start: September 10, 2021
• Primary Completion: April 14, 2022
• Study Completion: April 14, 2022
• Last Updated: May 31, 2022

Record last verified: 2022-05

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)