Abstract：
OBJECTIVE: To clarify the association between forced expiration and the abdominal muscles by assessing the relationship between expiratory mouth pressure and abdominal muscle activity in healthy young males.
METHODS: Twenty-five males underwent forced expiration at 20, 30, 50, 75, and 100% of the maximal expiratory mouth pressure. Mouth pressure was measured using a bridge-type transducer connected to a mouth pressure meter. Abdominal crunch, twist crunch, and abdominal hollowing at maximal voluntary contraction were also performed. During forced expiration and abdominal exercises, the activity of the rectus abdominis (RA), oblique externus abdominis/oblique internus abdominis (OE/OI), and OI/transversus abdominis (OI/TrA) was measured using surface electromyography.
RESULTS: The determination coefficient (r2) for the linear relationship between mouth pressure and abdominal muscle activity was 0.86 ± 0.15 for the RA, 0.93 ± 0.06 for the OE/OI, and 0.90 ± 0.14 for the OE/OI. The slope of the linear relationship with r2 ≥ 0.50 showed no significant difference between the RA (0.22 ± 0.27) and the OE/OI (0.27 ± 0.21). However, it was significantly greater in the OI/TrA (1.78 ± 1.41) than in the RA and OE/OI. The OE/OI activity was significantly lower in the maximal forced expiration than in twist crunch, and the OI/TrA activity was not significantly greater in the maximal forced expiration than in twist crunch.
CONCLUSIONS: All abdominal muscles contribute to forced expiration with a greater contribution of the OI and TrA than the RA and OE. Furthermore, the contribution of the TrA would be greater than that of the OI.
METHODS: Twenty-five males underwent forced expiration at 20, 30, 50, 75, and 100% of the maximal expiratory mouth pressure. Mouth pressure was measured using a bridge-type transducer connected to a mouth pressure meter. Abdominal crunch, twist crunch, and abdominal hollowing at maximal voluntary contraction were also performed. During forced expiration and abdominal exercises, the activity of the rectus abdominis (RA), oblique externus abdominis/oblique internus abdominis (OE/OI), and OI/transversus abdominis (OI/TrA) was measured using surface electromyography.
RESULTS: The determination coefficient (r2) for the linear relationship between mouth pressure and abdominal muscle activity was 0.86 ± 0.15 for the RA, 0.93 ± 0.06 for the OE/OI, and 0.90 ± 0.14 for the OE/OI. The slope of the linear relationship with r2 ≥ 0.50 showed no significant difference between the RA (0.22 ± 0.27) and the OE/OI (0.27 ± 0.21). However, it was significantly greater in the OI/TrA (1.78 ± 1.41) than in the RA and OE/OI. The OE/OI activity was significantly lower in the maximal forced expiration than in twist crunch, and the OI/TrA activity was not significantly greater in the maximal forced expiration than in twist crunch.
CONCLUSIONS: All abdominal muscles contribute to forced expiration with a greater contribution of the OI and TrA than the RA and OE. Furthermore, the contribution of the TrA would be greater than that of the OI.
摘要：
目的：通过评估健康年轻男性呼气口压与腹肌活动之间的关系，阐明强制呼气与腹肌之间的关系。
方法：25名男性在最大呼气口压的20、30、50、75和100％时被迫呼气。使用连接到口腔压力计的桥式传感器测量口腔压力。腹部紧缩，扭曲紧缩，并在最大自愿收缩时进行腹部空洞化。在强制呼气和腹部锻炼期间，腹直肌（RA）的活动，腹外斜/腹内斜（OE/OI），使用表面肌电图测量OI/腹横肌(OI/TrA)。
结果：对于RA，口腔压力与腹部肌肉活动之间的线性关系的测定系数（r2）为0.86±0.15，OE/OI为0.93±0.06，OE/OI为0.90±0.14。r2≥0.50的线性关系斜率在RA（0.22±0.27）和OE/OI（0.27±0.21）之间没有显着差异。然而,OI/TrA（1.78±1.41）明显高于RA和OE/OI。最大强制呼气时的OE/OI活性明显低于扭转紧缩时的OE/OI活性，最大强制呼气时的OI/TrA活性并不明显大于扭转紧缩时的OI/TrA活性。
结论：所有腹肌都有助于强制呼气，OI和TrA的贡献大于RA和OE。此外，TrA的贡献将大于OI的贡献。
方法：25名男性在最大呼气口压的20、30、50、75和100％时被迫呼气。使用连接到口腔压力计的桥式传感器测量口腔压力。腹部紧缩，扭曲紧缩，并在最大自愿收缩时进行腹部空洞化。在强制呼气和腹部锻炼期间，腹直肌（RA）的活动，腹外斜/腹内斜（OE/OI），使用表面肌电图测量OI/腹横肌(OI/TrA)。
结果：对于RA，口腔压力与腹部肌肉活动之间的线性关系的测定系数（r2）为0.86±0.15，OE/OI为0.93±0.06，OE/OI为0.90±0.14。r2≥0.50的线性关系斜率在RA（0.22±0.27）和OE/OI（0.27±0.21）之间没有显着差异。然而,OI/TrA（1.78±1.41）明显高于RA和OE/OI。最大强制呼气时的OE/OI活性明显低于扭转紧缩时的OE/OI活性，最大强制呼气时的OI/TrA活性并不明显大于扭转紧缩时的OI/TrA活性。
结论：所有腹肌都有助于强制呼气，OI和TrA的贡献大于RA和OE。此外，TrA的贡献将大于OI的贡献。
