Ingen positiv påverkan på genuttryck av kolhydratrestriktion efter träning

[Johaaan]

:)

 

 

 

The aim was to determine if the metabolic adaptations, particularly PGC‐1α and downstream metabolic genes were affected by restricting CHO following an endurance exercise bout in trained endurance athletes. A second aim was to compare baseline expression level of these genes to untrained. Elite endurance athletes (VO2max 66 ± 2 mL·kg−1·min−1, n = 15) completed 4 h cycling at ~56% VO2max. During the first 4 h recovery subjects were provided with either CHO or only H2O and thereafter both groups received CHO. Muscle biopsies were collected before, after, and 4 and 24 h after exercise. Also, resting biopsies were collected from untrained subjects (n = 8). Exercise decreased glycogen by 67.7 ± 4.0% (from 699 ± 26.1 to 239 ± 29.5 mmol·kg−1·dw−1) with no difference between groups. Whereas 4 h of recovery with CHO partly replenished glycogen, the H2O group remained at post exercise level; nevertheless, the gene expression was not different between groups. Glycogen and most gene expression levels returned to baseline by 24 h in both CHO and H2O. Baseline mRNA expression of NRF‐1, COX‐IV, GLUT4 and PPAR‐αgene targets were higher in trained compared to untrained. Additionally, the proportion of type I muscle fibers positively correlated with baseline mRNA for PGC‐1α, TFAM, NRF‐1, COX‐IV, PPAR‐α, and GLUT4 for both trained and untrained. CHO restriction during recovery from glycogen depleting exercise does not improve the mRNA response of markers of mitochondrial biogenesis. Further, baseline gene expression of key metabolic pathways is higher in trained than untrained.

 

Physiological Reports Published 12 February 2015 Vol. 3 no. e12184 DOI: 10.14814/phy2.12184
http://physreports.physiology.org/content/3/2/e12184

Ingen skillnad på genuttryck för masterregulatorer som PGC1Alpha (mitokondriell biogenes). Kolhydratssvält gav ingen positiv adaptation bara långsammare glykogenresyntes. 

[FredrikE]

http://www.svt.se/nyheter/vetenskap/sportdryck-kan-forstora-din-traning

 

Svensk forskning men med skillnaden av att träna "tom"(tömda glykogendepåer)

[Johaaan]

Jo precis, kanske lite mer kritiskt vad man gör före och under. Tanken var dock inte att skapa en LCHF-diskussion utan mest dela med mig av den nya studien, som är den första att kolla på effekterna över 4h efter på detta vis. Sympatiserar med att vanliga motionärer generellt inte bör använda sportdryck i sin vanliga träning med vissa undantag. Med låga depåer kan intensitet komma att kompromissas och effekter av mycket hög intensitet minskas.