|
|
|
|
|
|
|
Free Newsletters
Archive
My Subscriptions
News by Subject
News by Disease
News by Date
PLoS
Search News
Post Your News
JoVE
Job Seeker Login
Most Recent Jobs
Browse Biotech Jobs
Search Jobs
Post Resume
Career Fairs
Career Resources
For Employers
Regional News
US & Canada
Biotech Bay
Biotech Beach
Genetown
Pharm Country
BioCapital
BioMidwest
Bio NC
BioForest
Southern Pharm
BioCanada East
US Device
Europe
Asia
Market Summary
News
IPOs
Company Profiles
Companies
Events
Research Store
Biotech Events
Post an Event
Real Estate
Business Opportunities
|
|
|
|
PLoS By Category | Recent
PLoS Articles
|
|
Physiology
|
Energy Metabolism during Repeated Sets of Leg Press Exercise Leading to Failure or Not
Published:
Friday, July 13, 2012
Author:
Esteban M. Gorostiaga et al.
by Esteban M. Gorostiaga, Ion Navarro-Amézqueta, José A. L. Calbet, Ylva Hellsten, Roser Cusso, Mario Guerrero, Cristina Granados, Miriam González-Izal, Javier Ibañez, Mikel Izquierdo
This investigation examined the influence of the number of repetitions per set on power output and muscle metabolism during leg press exercise. Six trained men (age 34±6 yr) randomly performed either 5 sets of 10 repetitions (10REP), or 10 sets of 5 repetitions (5REP) of bilateral leg press exercise, with the same initial load and rest intervals between sets. Muscle biopsies (vastus lateralis) were taken before the first set, and after the first and the final sets. Compared with 5REP, 10REP resulted in a markedly greater decrease (P<0.05) of the power output, muscle PCr and ATP content, and markedly higher (P<0.05) levels of muscle lactate and IMP. Significant correlations (P<0.01) were observed between changes in muscle PCr and muscle lactate (R2?=?0.46), between changes in muscle PCr and IMP (R2?=?0.44) as well as between changes in power output and changes in muscle ATP (R2?=?0.59) and lactate (R2?=?0.64) levels. Reducing the number of repetitions per set by 50% causes a lower disruption to the energy balance in the muscle. The correlations suggest that the changes in PCr and muscle lactate mainly occur simultaneously during exercise, whereas IMP only accumulates when PCr levels are low. The decrease in ATP stores may contribute to fatigue.
More...
|
|
|
 |
|
|
|
|
|
|
|
|