Peoples Gregory E, Lee Daniel S, Notley Sean R, Taylor Nigel A S
Centre for Human and Applied Physiology, School of Medicine, University of Wollongong, Wollongong, NSW 2522, Australia.
Eur J Appl Physiol. 2016 Mar;116(3):635-46. doi: 10.1007/s00421-015-3323-5. Epub 2016 Jan 6.
Torso loads restrict chest-wall movement and ventilation, particularly during heavy exercise. Therefore, the differential impact of load carriage and chest-wall restriction was investigated during progressive treadmill exercise. In addition, acceptable work durations were derived across a wide range of submaximal, loaded exercise intensities.
Twelve males participated in two research phases. Phase 1: Three incremental treadmill tests until exhaustion [control (clothing only), load carriage (clothing plus 22-kg vest), and clothing with chest strapping]. Phase 2: Five steady-state exercise trials (clothing plus 22-kg vest) at intensities from 30 to 80 % of peak aerobic power to determine maximal acceptable work durations.
Maximal work tolerance [control 17.21 min (±0.93); loaded 13.44 min (±0.68); strapped 17.00 min (±0.83)] and the mass-specific peak aerobic power [control 61.61 mL kg(-1) min(-1) (±2.28); loaded 45.42 mL kg(-1) min(-1) (±1.41); strapped 59.99 mL kg(-1) min(-1) (±1.61)] were reduced only when loaded (P < 0.05). Peak minute ventilation was retained, although loading and chest strapping reduced the breathing reserve. The lower and upper acceptable work duration derivations when working at the 30 % intensity were 133.40 min (±23.77) and 220.10 min (±48.69), but at 80 % intensity, both durations were reduced to <7 min.
Thoracic loading significantly reduced exercise tolerance and the breathing reserve, but did not modify peak minute ventilation or the absolute peak aerobic power. Chest strapping, as used herein, exerted minimal impact. However, the projected maximal acceptable work durations were much less than derived using previously published methods.
躯干负荷会限制胸壁运动和通气，尤其是在剧烈运动期间。因此，本研究在递增式跑步机运动过程中，探究了负荷携带和胸壁限制的不同影响。此外，还得出了在广泛的次最大负荷运动强度下可接受的工作时长。
12名男性参与了两个研究阶段。阶段1：进行三次递增式跑步机测试直至力竭[对照组（仅着衣物）、负荷携带组（着衣物加22千克背心）和胸部绑扎衣物组]。阶段2：在峰值有氧功率的30%至80%强度下进行五次稳态运动试验（着衣物加22千克背心），以确定最大可接受工作时长。
最大工作耐力[对照组17.21分钟（±0.93）；负荷携带组13.44分钟（±0.68）；绑扎组17.00分钟（±0.83）]和质量比峰值有氧功率[对照组61.61毫升·千克⁻¹·分钟⁻¹（±2.28）；负荷携带组45.42毫升·千克⁻¹·分钟⁻¹（±1.41）；绑扎组59.99毫升·千克⁻¹·分钟⁻¹（±1.61）]仅在负荷携带时降低（P<0.05）。尽管负荷携带和胸部绑扎会减少呼吸储备，但分钟通气峰值得以保留。在30%强度下工作时，可接受工作时长的下限和上限分别为133.40分钟（±23.77）和220.10分钟（±48.69），但在80%强度下，两个时长均缩短至<7分钟。
胸部负荷显著降低了运动耐力和呼吸储备，但未改变分钟通气峰值或绝对峰值有氧功率。本文所用的胸部绑扎影响极小。然而，预计的最大可接受工作时长远低于使用先前发表方法得出的结果。
