PMID- 23142518
OWN - NLM
STAT- MEDLINE
DCOM- 20130708
LR  - 20131121
IS  - 1873-6815 (Electronic)
IS  - 0531-5565 (Linking)
VI  - 48
IP  - 2
DP  - 2013 Feb
TI  - Age related differences in maximal and rapid torque characteristics of the leg 
      extensors and flexors in young, middle-aged and old men.
PG  - 277-82
LID - S0531-5565(12)00297-5 [pii]
LID - 10.1016/j.exger.2012.10.009 [doi]
AB  - The decline in maximal and rapid isometric torque characteristics may compromise 
      functional living abilities in aging adults while loco-motor muscle groups, such 
      as the leg extensors and flexors, may exhibit different torque-time age related 
      decreases. The purpose of the present study was to examine the age-related 
      differences in maximal and rapid torque characteristics of the leg extensor and 
      flexor muscle groups in young, middle-aged, and old men. Sixty-five healthy men 
      were categorized by age as young (n=25; mean+/-SD age=24.9+/-3.0 years), middle-aged 
      (n=22; age=50.6+/-4.0 years), and old (n=18; age=66.8+/-4.5 years). Participants 
      performed maximal voluntary contractions (MVCs) of the leg extensors and flexors 
      and an estimated thigh cross sectional area (eThighCSA) assessment. Peak torque 
      (PT), peak rate of torque development (RTDpeak), absolute RTD and the contractile 
      impulse (IMPULSE) were calculated at time intervals of 30, 50, 100 and 200 ms 
      from the torque-time curve. Relative RTD was calculated at 10, 20, 30, 40 and 50% 
      of MVC from the normalized torque-time curves. PT, RTDpeak and later rapid torque 
      variables (RTD100, RTD200, and IMPULSE200) were greater (P</=0.05) in the young and 
      middle-aged when compared to the old men for both muscle groups. Early (RTD30,50; 
      IMPULSE30,50) and late (IMPULSE100) rapid torque variables were greater (P</=0.05) 
      for the young and middle-aged than the old men for the leg extensors but not the 
      leg flexors, except for RTD30, in which there was no difference between young and 
      old. There were no differences for all relative RTD variables between age groups 
      (P>0.05). eThighCSA was lower in the old compared to the young (P=0.001) and 
      middle-aged (P=0.016) men. Maximal and rapid torque characteristics were 
      preserved in middle-aged men but greatly reduced in older men with differential 
      effects at early and late portions of the torque-time curve between the leg 
      extensors and flexors. Significant decreases in absolute maximal and rapid torque 
      production with no change in relative RTD across age groups and lower eThighCSA 
      in old men may suggest that the loss of rapid torque producing capacities 
      observed in older men may be largely a function of mechanisms associated with 
      loss of muscle strength and muscle mass.
CI  - Copyright (c) 2012 Elsevier Inc. All rights reserved.
FAU - Thompson, Brennan J
AU  - Thompson BJ
AD  - Applied Musculoskeletal and Human Physiology Laboratory, Department of Health and 
      Human Performance, Oklahoma State University, Stillwater, OK, USA.
FAU - Ryan, Eric D
AU  - Ryan ED
FAU - Sobolewski, Eric J
AU  - Sobolewski EJ
FAU - Conchola, Eric C
AU  - Conchola EC
FAU - Cramer, Joel T
AU  - Cramer JT
LA  - eng
PT  - Comparative Study
PT  - Journal Article
DEP - 20121107
PL  - England
TA  - Exp Gerontol
JT  - Experimental gerontology
JID - 0047061
SB  - IM
MH  - Adult
MH  - Age Factors
MH  - Aged
MH  - *Aging
MH  - Analysis of Variance
MH  - Biomechanical Phenomena
MH  - Humans
MH  - *Isometric Contraction
MH  - Lower Extremity
MH  - Male
MH  - Middle Aged
MH  - *Muscle Strength
MH  - Muscle Strength Dynamometer
MH  - Quadriceps Muscle/*physiopathology
MH  - Random Allocation
MH  - Sarcopenia/*physiopathology
MH  - Time Factors
MH  - Torque
MH  - Young Adult
EDAT- 2012/11/13 06:00
MHDA- 2013/07/09 06:00
CRDT- 2012/11/13 06:00
PHST- 2012/09/18 00:00 [received]
PHST- 2012/10/25 00:00 [revised]
PHST- 2012/10/31 00:00 [accepted]
PHST- 2012/11/13 06:00 [entrez]
PHST- 2012/11/13 06:00 [pubmed]
PHST- 2013/07/09 06:00 [medline]
AID - S0531-5565(12)00297-5 [pii]
AID - 10.1016/j.exger.2012.10.009 [doi]
PST - ppublish
SO  - Exp Gerontol. 2013 Feb;48(2):277-82. doi: 10.1016/j.exger.2012.10.009. Epub 2012 
      Nov 7.