Training induced decrease in oxygen cost of cycling is accompanied by down-regulation of SERCA expression in human vastus lateralis muscle

• Autorzy: Majerczak J. , Karasinski J. , Zoladz J.A.
• Języki publikacji: EN

Abstrakty

EN

We have examined the effect of 5 week cycling endurance training program on the sarco(endo)plasmic reticulum Ca2+ ATPase isoforms (SERCA1 and 2) and myosin heavy chain (MyHC) in the vastus lateralis muscle as well as on the oxygen uptake to power output ratio (VO2/PO) during incremental cycling. Fifteen untrained men performed an incremental cycling exercise until exhaustion before and after moderate intensity training. Muscle biopsies were taken from vastus lateralis before and after training program. Training resulted in higher (P = 0.048) maximal oxygen uptake (VO2max) as well as in higher power output reached at VO2max (P = 0.0001). Moreover, lower (P = 0.02) VO2/PO ratio determined during incremental moderate intensity cycling (i.e. 30-120 W) as well as lower (P = 0.003) VO2/PO ratio reached at VO2max were observed after the training. A significant down regulation of SERCA2 protein (P = 0.03) and tendency (P = 0.055) to lower SERCA1 content accompanied by lower (P<10-4) plasma thyroid hormone concentration, with no changes (P = 0.67) in MyHC composition in vastus lateralis muscle were found after training. We have concluded that the increase in mechanical efficiency of cycling occurring during first weeks of endurance training is not related to changes in MyHC composition but it may be due to down-regulation of SERCA pumps.

Słowa kluczowe

EN

sarcoplasmic reticulum; vastus lateralis muscle; oxygen; endoplasmic reticulum; myosin heavy chain; cycling endurance training; SERCA2 protein regulation; skeletal muscle; endurance training

• Wydawca: -
• Czasopismo: Journal of Physiology and Pharmacology
• Rocznik: 2008
• Tom: 59
• Numer: 3
• Opis fizyczny: p.589-602,fig.,ref.

Twórcy

autor

Majerczak J.

• University School of Physical Education, Al.Jana Pawla II 78, 31-571 Krakow, Poland

autor

Karasinski J.

autor

Zoladz J.A.