Low-volume strength and endurance training prevent the decrease in exercise hyperemia induced by non-dominant forearm immobilization.
We examined the effect of 3-week upper limb immobilization on conduit artery cross-sectional area and peak hyperemia (BF(peak)) after exhaustive dynamic handgrip exercise (Ex(dyn)), and that of low-volume strength and endurance training during immobilization. Healthy volunteers (n = 21; mean age, 22 years) were divided into 3 groups: immobilization only (IMM; n = 7), immobilization with training (STR + END; n = 7), and control (no immobilization or training, CNT; n = 7). Endurance training comprised Ex(dyn) at 30% maximum voluntary contraction (MVC) (duration of each session, ~60 s; twice weekly). Strength training involved intermittent isometric handgrip exercise at 70% MVC (duration of each session, 40 s; twice weekly), repeated 10 times. We used ultrasound methods to measure the brachial artery cross-sectional area and the BF(peak) after Ex(dyn) for 5 min pre- and post-immobilization. We found a significant group by time interaction in BF(peak) (p < 0.05). A significant decrease was found in BF(peak) in the IMM (p < 0.05) between pre- and post-immobilization and a protective effect in the STR + END. The 3-week upper limb immobilization did not influence the baseline artery cross-sectional area. In conclusion, BF(peak) decreased after 3-week upper limb immobilization and a combination of strength training and endurance training preserved the blunted BF(peak).
Ohmori
Fumiko
F
National Institute of Fitness and Sports in Kanoya, 1 Shiromizu, Kanoya, Kagoshima, 891-2393, Japan.
Hamaoka
Takafumi
T
Shiroishi
Kiyoshi
K
Osada
Takuya
T
Murase
Norio
N
Kurosawa
Yuko
Y
Ichimura
Shiro
S
Homma
Toshiyuki
T
Esaki
Kazuki
K
Kime
Ryotaro
R
Katsumura
Toshihito
T
D015444:Exercise / Q000502:physiology*; D005542:Forearm / Q000098:blood supply / Q000502:physiology; D018737:Hand Strength / Q000502:physiology; D006801:Humans; D006940:Hyperemia / Q000503:physiopathology*; D007103:Immobilization / Q000379:methods*; D007537:Isometric Contraction / Q000502:physiology; D008297:Male; D010807:Physical Endurance / Q000502:physiology*; D055070:Resistance Training / Q000379:methods*; D055815:Young Adult