Heterogeneity in subcellular muscle glycogen utilisation during exercise impacts endurance capacity in men

@article{Jensen2020HeterogeneityIS,
  title={Heterogeneity in subcellular muscle glycogen utilisation during exercise impacts endurance capacity in men},
  author={Rasmus Jensen and Niels {\O}rtenblad and Marie-Louise Holleufer Stausholm and Mette Carina Skjaerbaek and Daniel Nyberg Larsen and Mette Hansen and Hans-Christer Holmberg and Peter Plomgaard and Joachim Nielsen},
  journal={The Journal of Physiology},
  year={2020},
  volume={598}
}
When muscle biopsies first began to be used routinely in research on exercise physiology five decades ago, it soon become clear that the muscle content of glycogen is an important determinant of exercise performance. Glycogen particles are stored in distinct pools within the muscles, but the role of each pool during exercise and how this is affected by diet is unknown. Here, the effects of diet and exercise on these pools, as well as their relation to endurance during prolonged cycling were… Expand
Intramyofibrillar glycogen drives endurance exercise capacity
  • J. Fisher
  • Medicine
  • The Journal of physiology
  • 2020
TLDR
The areas of the discs corresponding to the intracellular glycogen depots follow the findings of Jensen et al. (2020), which show that intramyofibrillar glycogen in type I fibres best correlates with exercise performance, and high starting subsarcolemmal glycogen appears related to sparing of the Intramy ofibrillAR glycogen depot. Expand
Muscle Glycogen Metabolism and High-Intensity Exercise Performance: A Narrative Review
TLDR
Emerging evidence points to a direct coupling between muscle glycogen and steps in the excitation–contraction coupling including altered muscle excitability and calcium kinetics during single and intermittent bouts of high-intensity exercise. Expand
Carbohydrate improves exercise capacity but does not affect subcellular lipid droplet morphology, AMPK and p53 signalling in human skeletal muscle
TLDR
It is reported for the first time that exercise reduces IMTG content in both central and peripheral regions of type I and IIa fibres, reflective of decreased LD number in both fibre types whereas reductions in LD size were exclusive to type I fibres. Expand
Location location location: muscle glycogen content and endurance exercise
TLDR
Whole-muscle quantification might not be the most accurate method to elucidate the complex pathways through which muscle glycogen availability may influence exercise performance, and instead, single-fibre and subcellular localisation may further enhance understanding of this topic. Expand
Subcellular localization‐ and fibre type‐dependent utilization of muscle glycogen during heavy resistance exercise in elite power and Olympic weightlifters
TLDR
The hypothesis of the present study was that high‐volume heavy‐load resistance exercise would mediate a pattern of substantial glycogen depletion in specific subcellular localizations and fibre types. Expand
Glycogen supercompensation is due to increased number, not size, of glycogen particles in human skeletal muscle
TLDR
Using transmission electron microscopy to inspect individual glycogen particles visually, it is shown that glycogen supercompensation is achieved by increasing the number of particles while keeping them at submaximal sizes. Expand
The Validity of Ultrasound Technology in Providing an Indirect Estimate of Muscle Glycogen Concentrations Is Equivocal
TLDR
Current evidence that MuscleSound® technology can provide valid and actionable information around muscle glycogen stores is at best equivocal. Expand
Pharmacological but not physiological GDF15 suppresses feeding and the motivation to exercise
TLDR
It is shown that prolonged endurance exercise increases circulating GDF15 to levels otherwise only observed in pathophysiological conditions, and this exercise-induced increase can be recapitulated in mice and is accompanied by increased Gdf15 expression in the liver, skeletal muscle, and heart muscle. Expand

References

SHOWING 1-10 OF 81 REFERENCES
Human skeletal muscle glycogen utilization in exhaustive exercise: role of subcellular localization and fibre type
TLDR
It is shown that after prolonged exhaustive exercise the depletion of glycogen stores is dependent on its localization within the muscle cells, and consideration of distinct localizations within the muscles may advance understanding of how and why low muscle glycogen content impairs muscle function. Expand
Enhanced Glycogen Storage of a Subcellular Hot Spot in Human Skeletal Muscle during Early Recovery from Eccentric Contractions
TLDR
In the carbohydrate-supplemented state, the effect of eccentric contractions on glycogen metabolism depends on the subcellular localization, muscle fiber’s oxidative capacity, and the time course of recovery. Expand
Skeletal Muscle Glycogen Content at Rest and During Endurance Exercise in Humans: A Meta-Analysis
TLDR
The effects of fitness, acute dietary carbohydrate (CHO) availability and other factors on muscle glycogen concentration at rest and during exercise of different durations and intensities were meta-analyse. Expand
Glycogen depletion patterns in human skeletal muscle fibers during prolonged work
TLDR
The glycogen depletion pattern in human muscle fibers was followed throughout the course of prolonged exercise at a work load requiring 67% of the subjects' maximal aerobic power, suggesting a preferential utilization of ST fibers during prolonged, intense exercise. Expand
Muscle glycogen and cell function – Location, location, location
TLDR
It is proposed that the effect of low muscle glycogen on excitation‐contraction coupling may serve as a built‐in mechanism, which links the energetic state of the muscle fiber to energy utilization. Expand
Postexercise muscle glycogen resynthesis in humans.
TLDR
Dietary strategies that can enhance glycogen synthesis from suboptimal amounts of CHO or energy intake are of practical interest to many athletes; in this scenario, the coingestion of protein with CHO can assist glycogen storage. Expand
Quantitative assessment of human muscle glycogen granules size and number in subcellular locations during recovery from prolonged exercise
TLDR
Glycogen granules varied in size and number depending on location, and in all compartments resynthesis of glycogen was characterized initially by an increase in granule number and later by a increase in size. Expand
Local depletion of glycogen with supramaximal exercise in human skeletal muscle fibres
TLDR
The results obtained in the present study help to understand the muscle metabolic dynamics of whole body repeated supramaximal exercise, and suggest that the muscle has a compartmentalized local adaptation to repeated exercise, which affects glycogen depletion. Expand
Carbohydrate supplementation during prolonged cycling exercise spares muscle glycogen but does not affect intramyocellular lipid use
TLDR
It is concluded that carbohydrate supplementation during prolonged cycling exercise does not modulate IMTG use but spares muscle glycogen use during the initial stages of exercise in endurance-trained men. Expand
Carbohydrate ingestion and single muscle fiber glycogen metabolism during prolonged running in men.
TLDR
It is proposed that CHO ingestion improved endurance capacity by contributing to oxidative ATP production specifically in type I fibers and by doing so delayed the development of glycogen depletion in this fiber type. Expand
...
1
2
3
4
5
...