Keywords microgravity/simulated microgravity;countermeasures;exercise;orthostatic tolerance;heart rate variability;muscle atrophy;cardiovascular function;cerebral blood flow;

• 关键词失重/模拟失重;对抗措施;体育锻炼;立位耐力;心率变异性;肌肉萎缩;心脏功能;脑血流;