A cycle ergometer is a stationary cycling
apparatus with built-in mechanisms
that can alter the work done by the person
who is exercising. Among healthy
subjects, exercise with a cycle ergometer
preserved anterior thigh muscle thickness
during prolonged immobilization
(33). With bedside cycle ergometers, patients
can exercise through passive, active-assisted,
or active training (Fig. 2).
Consequently, cycle ergometry may be
feasible for sedated, immobile patients
with severe critical illness where even
passive range of motion may play a role in
preserving muscle architecture (34). Despite
its potential benefits, rigorous evaluation
of cycle ergometry as a rehabilitation
therapy for hospitalized patients has
been limited. An observational study of
cycle ergometry during hemodialysis for
22 outpatients demonstrated its safety
and feasibility in this patient population
(35). Similarly, safety and feasibility were
demonstrated in another study of nine
bed-bound patients with severe COPD
(36). Cycle ergometry has also been evaluated
in ambulatory patients with COPD,
where it is frequently combined with inspiratory
muscle training (37, 38).
The safety, feasibility, and efficacy of
cycle ergometry in the ICU setting have
been evaluated in a recently randomized,
controlled trial of 90 medical and surgical
ICU patients (39). Patients were eligible
for the study if: 1) on or after ICU day 5,