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Completed

NCT Number: NCT03749785

Carbohydrate Feeding Frequency, Muscle Glycogen and Exercise Capacity in Runners

The aim of this study is to investigate the effects of regular sucrose feeds compared to a single large bolus given late in exercise, on muscle glycogen utilisation, exercise capacity and other markers of metabolism during running

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Key information

Conditions

Exercise Behavior Motor Activity

Age range

18 year–50 year

Sex eligibility

Male

Study type

Interventional

Phase

Not applicable

Primary location

Department for Health, University of Bath

Bath, BA2 7AY, United Kingdom

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Self-identify as a trained runner
  • Regularly participate in running activity (>2 times a week)
  • Participated in running based training for a minimum of 2 years
  • Be willing to undertake exercise sessions until volitional exhaustion
  • Be willing to have the necessary samples taken during the testing protocols
  • Not a habitual smoker
  • Have the capacity and willingness to provide informed consent (oral and written)
  • Successful completion of the physical activity readiness questionnaire (PAR-Q)

Exclusion criteria

  • Female
  • <18 or >50 years old
  • Not regularly participating in running activity (<3 times a week)
  • Experience contraindications to the administration of the proposed anaesthetic (Lidocaine Hydrochloride)
  • Habitual/previously habitual smoker

Treatment and study plan

Regular carbohydrate feeding

Other

60 ml of water with 5 g sucrose given every 5 minutes 14 times up until 70 minutes followed by 5 g sucrose after 75 minutes in a 250 ml solution

Single carbohydrate bolus

Other

60 ml of water given every 5 minutes 14 times up until 70 minutes followed by 75 g sucrose after 75 minutes in a 250 ml solution

Primary outcomes

  1. Muscle glycogen concentrations

    Time frame: Estimated to be between 90 and 145 minutes

    Muscle glycogen concentration at rest, after 75 minutes of treadmill running and at volitional exhaustion. Measured using the bergstrom needle technique for obtaining muscle biopsy samples

  2. Exercise capacity

    Time frame: Estimated to be between 90 and 145 minutes

    Time to exhaustion at the pre-determined speed to elicit exhaustion after ~90 minutes when ingesting water only

Secondary outcomes

  1. Ratings of perceived exertion

    Time frame: Estimated to be between 90 and 145 minutes

    Subjective ratings of perceived exertion, during treadmill running. Measured using a borg scale of 6 to 20, where 6 = no exertion at all, and 20 = maximal exertion.

  2. Ratings of stomach discomfort

    Time frame: Estimated to be between 90 and 145 minutes

    Subjective ratings of stomach discomfort during treadmill running. Measured using a modified borg scale of 6 to 20, where 6 = no discomfort and 20 = maximal discomfort

  3. Carbohydrate oxidation

    Time frame: Estimated to be between 90 and 145 minutes

    Total carbohydrate oxidation during treadmill running. Measured using indirect calorimetry and reported in grams.

  4. Fat oxidation

    Time frame: Estimated to be between 90 and 145 minutes

    Total fat oxidation during treadmill running. Measured using indirect calorimetry and reported in grams.

  5. Plasma glucose concentrations

    Time frame: Estimated to be between 90 and 145 minutes

    Plasma lactate concentrations during of treadmill running. Measured using colourimetric assay and reported in mmol/L

  6. Plasma lactate concentrations

    Time frame: Estimated to be between 90 and 145 minutes

    Plasma lactate concentrations during treadmill running. Measured using colourimetric assay and reported in mmol/L.

  7. Heart rate

    Time frame: Estimated to be between 90 and 145 minutes

    Heart rate during treadmill running measured by telemetry and reported in beats per minute

  8. Rate of oxygen consumption

    Time frame: Estimated to be between 90 and 145 minutes

    Rate of oxygen consumption during treadmill running. Measured using indirect calorimetry and reported in litres per minute

  9. Rate of carbon dioxide production

    Time frame: Estimated to be between 90 and 145 minutes

    Rate of carbon dioxide production during treadmill running. Measured using indirect calorimetry and reported in litres per minute.

Sponsors and collaborators

Lead sponsor

University of Bath

Other

Registry information

Official study title

The Effect of Carbohydrate Feeding Frequency on Muscle Glycogen and Exercise Capacity in Runners

Important dates

Study start
2018
Primary completion
2019
Study completion
2019
First posted
Nov 21, 2018
Registry last updated
Nov 1, 2019

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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