In recent years, due to the improvement in the survival rate of the intensive care unit, the problem of severe systemic fatigue (Intensive care unit acquired weakness; ICUAW) has continued to receive attention. Muscle mass decreases by 3-11% within a week, resulting in decreased muscle strength and muscle atrophy. Current studies suggest that ICUAW can lead to poorer function, prolonged ICU stay, and decreased quality of life.

This study aimed to understand the muscle strength of critically ill patients and to explore the effect of exercise intervention on improving muscle strength. The experimental group received a four-week exercise bike intervention plus conventional rehabilitation exercises, while the control group received conventional rehabilitation exercises.

The content of the exercise is to use an exercise bike, start pedaling on the first day, time setting: 20 minutes, speed: 2, and adopt passive mode. If you can complete the exercise on the first day, the time will be adjusted to 30 minutes on the second day. If you cannot complete the exercise on the first day, the time will still start from 20 minutes on the second day. The maximum time is 30 minutes. If you can complete 30 minutes of passive exercise for 3 consecutive days, the fourth day will be adjusted to active exercise. The entire exercise training is seven days a week, once a day, once a 30-minute, at least 5 days. Those who were discharged to the general ward continued to complete this exercise training for up to 28 days. Stop exercising if heartbeat > 140, mean arterial pressure < 65, blood oxygen < 90%, respiration > 35 beats/min, or the patient requests to stop during exercise.

Inclusion Criteria:

1. Aged over 20 years old
2. Conscious
3. willing to participate in this study, and signed the consent form
4. no lower extremity activity taboo, and can walk independently before admission

Exclusion Criteria:

1. Have neuromuscular disease.
2. Unable to step on a bed bike.