High-intensity flywheel exercise and recovery of atrophy after 90 days bed-­rest­

Aims To investigate differential muscle atrophy during bed-rest, the impact of a high-intensity concentric-eccentric (flywheel) resistance exercise countermeasure and muscle recovery after bed-rest. Methods Twenty-five healthy male subjects underwent 90 dayshead-down tilt bed-rest. Volume of individual lower-limb muscles was measured via MRI before, twice during and four times up to 1 year after bed-rest. Subjects were either inactive (n=16) or performed flywheel exercise every third day of bed-rest (n=9). Functional performance was assessed via countermovement jump. Results On ‘intent-to-treat’ analysis, flywheel prevented atrophy in the vasti (p Conclusion The exercise countermeasure was effective in preventing or reducing atrophy in the vasti, adductor magnus and ankle dorsiflexors/toe flexors but not the hamstrings, medial thigh muscles or peroneals and dorsiflexor muscles. Trial registration number NCT00311571; results.