Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Pro- and macroglycogenolysis: relationship with exercise intensity and duration.

T E Graham1, K B Adamo, J Shearer

  • 1Human Biology and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada N1G 2W1. terrygra@uoguelph.ca

Journal of Applied Physiology (Bethesda, Md. : 1985)
|February 22, 2001
PubMed
Summary

Human skeletal muscle utilizes two glycogen pools, proglycogen (PG) and macroglycogen (MG), during exercise. PG is mobilized more readily than MG, indicating distinct metabolic regulation for each pool.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Musculoskeletal Injuries, Exercise Behaviors, and Reproductive Health Are Related to Physical Fitness of Female First-Responders and Health Care Providers.

Women's health reports (New Rochelle, N.Y.)·2024
Same author

Are physical fitness, a history of childbirth and injury history related to knee valgus in female Canadian Armed Forces members during a bodyweight overhead squat movement?

BMJ military health·2024
Same author

History of childbirth as a potential risk factor for musculoskeletal injury in military personnel.

BMJ military health·2023
Same author

Metabolomics to understand placental biology: Where are we now?

Tissue & cell·2021
Same author

To HIIT or not to HIIT? The question pregnant women may be searching for online: a descriptive observational study.

Perspectives in public health·2021
Same author

Mobile telephone delivered contingency management for encouraging adherence to supervised methadone consumption: feasibility study for an RCT of clinical and cost-effectiveness (TIES).

Pilot and feasibility studies·2021

Area of Science:

  • Exercise Physiology
  • Muscle Metabolism
  • Biochemistry

Background:

  • Skeletal muscle glycogen serves as a primary energy source during physical activity.
  • Glycogen exists in distinct pools within muscle cells, potentially with differential mobilization rates.
  • Understanding glycogen pool dynamics is crucial for optimizing athletic performance and metabolic health.

Purpose of the Study:

  • To investigate the net catabolism rates of proglycogen (PG) and macroglycogen (MG) in human skeletal muscle during various exercise intensities and durations.
  • To compare the mobilization and regulation of PG and MG pools under different exercise conditions.
  • To elucidate potential differences in the metabolic control mechanisms governing PG and MG utilization.

Main Methods:

  • Muscle biopsies were obtained from 21 male subjects at rest and during/after exercise protocols of varying intensities (70%, 85%, 100% VO2 max) and durations.

Related Experiment Videos

  • Glycogen concentrations ([PG] and [MG]) and net glycogenolysis rates were measured in muscle samples.
  • Subjects were divided into three groups based on exercise protocol to assess glycogen utilization under different physiological stresses.

    • Main Results:

    • Proglycogen (PG) demonstrated higher and more variable net catabolism rates compared to macroglycogen (MG) across exercise conditions.
    • PG concentration ([PG]) decreased significantly during exercise, particularly in the initial stages, while [MG] showed less pronounced changes.
    • Macroglycogen (MG) appeared more resistant to mobilization, with its catabolism being more rapidly inhibited once activated, suggesting differential regulation.

    Conclusions:

    • The two glycogen pools, PG and MG, exhibit distinct mobilization patterns and rates during exercise in human skeletal muscle.
    • PG is preferentially mobilized over MG, especially during high-intensity exercise.
    • These findings suggest that separate metabolic regulatory pathways control the utilization of PG and MG pools during physical exertion.