To determine rehabilitation exercise program effects under hormone deficient (ovariectomy or OVX) and hormone supplemented [OVX + @entity53 (E2)] conditions. Mature female @entity35 (n = 123) were assigned to OVX or OVX + E2-supplemented groups. OVX and OVX + E2 groups were allocated to one of four conditions: (1) control, (2) hindlimb unweighted (HLU) for 4 weeks to induce @entity2057 , (3) cage Recovery for 2 weeks after HLU, and (4) Recovery with 2 weeks of rehabilitation exercise program after 4 weeks of HLU. @entity194 following HLU was comparable for OVX and OVX + E2-supplemented @entity35 and was significant in all muscles examined (soleus, tibialis anterior, plantaris, gastrocnemius, quadriceps). Also significant with HLU was the decline in muscle force (P < 0.05) in soleus, plantaris, gastrocnemius and tibialis anterior (quadriceps not tested). There were trends toward return of muscle mass in Recovery OVX and Recovery OVX + E2 groups but only the E2 supplemented OVX @entity35 had return of muscle mass (4/5 muscles studied) with exercise. Peak tetanic tension (Po) returned to control values in the E2 supplemented Exercise @entity35 but not in the unsupplemented Exercise group. For example, gastrocnemius Po for OVX HLU, OVX Recovery and OVX-Exercise groups was 82%*, 82%* and 76%* of control. Gastrocnemius Po for E2 supplemented HLU, Recovery and Exercise groups was 72%*, 95% and 106% of control (*P < 0.05 compared to control). H_E cross-sections from OVX-Exercise @entity35 showed central nuclei. In conclusion, a rehabilitation exercise program to remediate acute @entity194 in females appears more effective if E2 is present.

A rehabilitation exercise program to remediate skeletal XXXX in an estrogen-deficient organism may be ineffective.

@entity35 :: ('10116', 'Species') :: ['rats'] @entity2057 :: ('MESH:D009133', 'Disease') :: ['muscle atrophy'] @entity194 :: ('MESH:D001284', 'Disease') :: ['atrophy', 'Atrophy'] @entity53 :: ('MESH:D004958', 'Chemical') :: ['17-beta estradiol']
@entity2057 :: (MESH:D009133,Disease) :: ['muscle atrophy']
