The Sports Medicine and Rehabilitation Division, The Zinman College of Physical Education and Sport Sciences at the Wingate Institute , Israel.
J Sports Sci Med. 2006 Jun 1;5(2):202-7. eCollection 2006.
Backpack carriage occurs in day-to-day tasks and has applications in school, physical training, recreational activities and sports. Using metabolic cart and echocardiograph, this study determined and examined the effects of two different load carriages on left ventricular function during 30 min. of treadmill walking in healthy adolescent male subjects. Seventeen males (13.1 ± 0.5 yrs.) walked on a treadmill at a speed of 4 km·h(-1), each carrying a load relative to his body mass at 333 gr·kg(-1) body weight during one session and without weight during the other session. Significant (p < 0.05) differences were noted between the 333 gr·kg(-1) body weight and the no weights with regard to: VO2 13.6 ± 1.3 and 10.5 ± 1.1 ml·kg(-1)·min(-1); heart rate: 133.2 ± 7.1 and 121.4 ± 5.6 beats·min(-1); mean arterial blood pressure; 95. 4 ± 4.3 and 87.5 ± 3.8 mmHg and systolic blood pressure 147.7 ± 7.0 and 129.8 ± 7.1 mmHg respectively. No significant differences were noted between the two exercises with regard to left ventricular function variables. This study suggests that in adolescents as in adults, the vasodilatation mechanism dominates during combined dynamic and isometric exercises. Thus, the opposing force to the left ventricular ejection is reduced which in turn does not change the left ventricular global function. In addition, the vasodilatation mechanism enables oxygen supply to the contracting muscles via aerobic energy pathways. Key PointsThis study suggests that in adolescents as in adults, the vasodilatation mechanism dominates during combined dynamic and isometric exercises.Thus, the opposing force to the left ventricular ejection is reduced which in turn does not change the left ventricular global function.In addition, the vasodilatation mechanism enables oxygen supply to the contracting muscles via aerobic energy pathways.
背包式推车在日常任务中很常见，在学校、体能训练、娱乐活动和运动中都有应用。本研究使用代谢车和超声心动图，在 17 名健康青少年男性中，确定并检查了两种不同的负载在 30 分钟的跑步机行走过程中对左心室功能的影响。每个参与者在一次会话中携带相对于其体重的 333 克/公斤体重的负载，而在另一次会话中不携带负载。与不携带重量相比，333 克/公斤体重和不携带重量之间存在显著差异（p < 0.05），包括：VO2 为 13.6 ± 1.3 和 10.5 ± 1.1 ml·kg(-1)·min(-1)；心率：133.2 ± 7.1 和 121.4 ± 5.6 次/分钟；平均动脉血压：95.4 ± 4.3 和 87.5 ± 3.8 mmHg，收缩压 147.7 ± 7.0 和 129.8 ± 7.1 mmHg。在左心室功能变量方面，两种运动之间没有显著差异。本研究表明，青少年和成年人一样，在动态和等长运动相结合时，血管舒张机制占主导地位。因此，左心室射血的拮抗力降低，这反过来又不会改变左心室的整体功能。此外，血管舒张机制使含氧血液通过有氧能量途径供应给收缩的肌肉。关键点本研究表明，青少年和成年人一样，在动态和等长运动相结合时，血管舒张机制占主导地位。因此，左心室射血的拮抗力降低，这反过来又不会改变左心室的整体功能。此外，血管舒张机制使含氧血液通过有氧能量途径供应给收缩的肌肉。
