2. |
- Nielsen, Joachim, et al.
(författare)
-
Skeletal muscle glycogen content and particle size of distinct subcellular localizations in the recovery period after a high-level soccer match
- 2012
-
Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 112:10, s. 3559-3567
-
Tidskriftsartikel (refereegranskat)abstract
- Whole muscle glycogen levels remain low for a prolonged period following a soccer match. The present study was conducted to investigate how this relates to glycogen content and particle size in distinct subcellular localizations. Seven high-level male soccer players had a vastus lateralis muscle biopsy collected immediately after and 24, 48, 72 and 120 h after a competitive soccer match. Transmission electron microscopy was used to estimate the subcellular distribution of glycogen and individual particle size. During the first day of recovery, glycogen content increased by ~60% in all subcellular localizations, but during the subsequent second day of recovery glycogen content located within the myofibrils (Intramyofibrillar glycogen, a minor deposition constituting 10–15% of total glycogen) did not increase further compared with an increase in subsarcolemmal glycogen (−7 vs. +25%, respectively, P = 0.047). Conversely, from the second to the fifth day of recovery, glycogen content increased (53%) within the myofibrils compared to no change in subsarcolemmal or intermyofibrillar glycogen (P < 0.005). Independent of location, increment in particle size preceded increment in number of particles. Intriguingly, average particle size decreased; however, in the period from 3 to 5 days after the match. These findings suggest that glycogen storage in skeletal muscle is influenced by subcellular localization-specific mechanisms, which account for an increase in number of glycogen particles located within the myofibrils in the period from 2 to 5 days after the soccer match.
|
|