CHANGES IN MUSCLE THICKNESS, PENNATION ANGLE AND FASCILE LENGTH WITH AGING

Abstract

The influences of age on muscle architectural characteristics ， Le ． ， muscle thickness ， pennation angle ， fascicle length ， were studied in 121 men and 229 women aged ユ7 to 85 yrs ． The subjects were divided into three age groups （ younger ： 17 − 39 yrs、 middle − aged ： 40 − 59 yrs ， elderly ： 60 − 85 yrs ）for boヒh genders ． Muscle thickness and pennatien ang ］ eof the vastus lateralis （ VL ） ， medial gastrocne ． mius （ MG ） ， and long head of triceps brachii （ TB ｝muscles were measured using B − mode ul し raso ． nQgraphy ， and fascicle Iength was estima し ed ． 1n all age groups ， men had signiflcantly greater relative muscle thickness （ to limb tength） in VL and TB than wome 冂 ， bロ t not in MG ， Relative muscle thick ・ ness of VL was significant ［ y IDwer in elderlythan in youngerand middle − aged subjects ， However ， the eorr ∈sponding differences ［ n MG and TB were insignificant ， The pennation angl ∈ ofVL was significantly lower in elderly than in yeungerand m 五 ddle − aged subjects ， although there were no signifieant differences in pennation ang 且 ∈s of MG and TB among the three groups ． These results suggest that the decrease in thickness of vastuslateralLs muscle with aging issignificant ， but not signi 「 icant for medial gastrocnemius and Lriceps brachii muscles ， （ Jpn． 亅 ． Phys ． Fitness Sports Med ． 2003， 52 Supp1 ： 119 〜 126） key word ： pennation ， fascicte ， muscle し hickness， ultrasonograph 1 ．緒 γo ， κomaba 〒 153 − 8902 東 京都 目黒 区 駒 場 3 − 8 − 1 3 − 8 − 1 ， Megtiro − ku ， Tokyo 153 − 8． 902， ノ apa η N 工 工 一 Eleotronio