Table 3.
Body composition
| Study Groups | Study Phases |
Percent Changes | ||||
|---|---|---|---|---|---|---|
| Baseline (B) | Bed Rest (BR) | Recovery (R) | BR − B | R − BR | R − B | |
| Body weight, kg | ||||||
| AA | 80.4±2.9 | 76.7±2.5 | 78.5±2.6 | −4.6±0.8% | 2.3±0.9% | −2.4±1.9% |
| RT | 83.0±2.7 | 80.8±2.5 | 81.2±2.5 | −2.7±1.2% | 0.5±1.1% | −2.1±2.1% |
| AART | 83.3±2.4 | 81.3±2.2 | 81.0±2.3 | −2.4±1.1% | −0.4±1.1% | −2.7±0.6% |
| P value, time-by-group interactions: | 0.60 | 0.12 | 0.79 | |||
| Lean body mass by DXA, kg | ||||||
| AA | 59.5±2.5 | 57.7±2.4 | 58.1±2.3 | −3.0±1.8% | 0.7±2.5% | −2.3±2.2% |
| RT | 63.6±1.9 | 62.6±1.9 | 63.0±2.0 | −1.5±1.8% | 0.6±1.8% | −0.9±2.3% |
| AART | 63.7±1.7 | 62.2±1.6 | 63.3±1.8 | −2.3±1.2% | 1.8±1.3% | −0.6±1.2% |
| P value, time-by-group interactions: | 0.34 | 0.75 | 0.69 | |||
| Leg lean mass by DXA, kg | ||||||
| AA | 9.9±0.4 | 9.2±0.4 | 9.5±1.0 | −7.1±1.5% | 3.3±3.5% | −4.0±3.4% |
| RT | 10.8±0.4 | 10.3±0.3 | 10.6±1.3 | −4.6±1.9% | 3.0±1.6% | −1.9±1.8% |
| AART | 10.6±0.3 | 10.1±0.3 | 10.4±1.1 | −4.7±1.7% | 3.0±1.9% | −1.9±1.9% |
| P value, time-by-group interactions: | 0.05 | 0.96 | 0.21 | |||
| Arm lean mass by DXA, kg | ||||||
| AA | 3.8±0.3 | 3.8±0.2 | 3.7±0.3 | 0±3.9% | −2.6±3.3% | −2.6±4.5% |
| RT | 4.1±0.2 | 4.3±0.2 | 4.2±0.2 | 4.9±3.1% | −2.3±3.5% | 2.4±2.9% |
| AART | 4.3±0.2 | 4.3±0.2 | 4.4±0.2 | 0±3.2% | 2.3±3.0% | 2.3±2.3% |
| P value, time-by-group interactions: | 0.09 | 0.67 | 0.06 | |||
| Body fat by DXA, % | ||||||
| AA | 25.0±1.0 | 25.9±1.1 | 25.5±1.2 | 3.6±2.3% | −1.5±3.4% | 2.0±3.7% |
| RT | 23.0±1.3 | 21.8±1.3 | 21.0±1.2 | −5.2±4.0% | −3.7±2.4% | −8.7±3.8% |
| AART | 20.6±1.3 | 20.4±1.3 | 19.7±1.3 | −1.0±3.8% | −3.4±2.8% | −4.4±3.2% |
| P value, time-by-group interactions: | 0.002 | 0.09 | <0.001 | |||
| Midthigh muscle area by CT, cm2 | ||||||
| AA | 153.1±7.1 | 135.8±6.6 | 142.2±8.0 | −11.3±3.9% | 4.7±5.8% | −7.1±3.9% |
| RT | 168.4±6.4 | 163.1±6.8 | 165.8±7.4 | −3.1±2.9% | 1.6±3.2% | −1.5±3.9% |
| AART | 156.2±4.0 | 150.1±4.4 | 150.5±4.4 | −4.0±1.7% | 0.3±2.5% | −3.6±2.0% |
| P value, time-by-group interactions: | <0.001 | 0.13 | <0.001 | |||
| Midthigh intramuscular fat area by CT, cm2 | ||||||
| AA | 2.1±1.2 | 2.4±1.4 | 2.2±1.1 | 14.3±7.2% | −8.3±8.7% | 4.8±9.4% |
| RT | 2.2±1.2 | 2.1±1.1 | 1.9±1.0 | −4.5±9.7% | −9.5±9.7% | −13.6±9.1% |
| AART | 2.0±1.2 | 1.9±1.4 | 2.0±1.5 | −5.0±6.4% | 5.3±8.7% | 0±9.2% |
| P value, time-by-group interactions: | 0.04 | 0.24 | 0.05 | |||
| Midthigh subcutaneous fat area by CT, cm2 | ||||||
| AA | 44.0±18.9 | 47.1±18.8 | 46.4±16.4 | 7.0±11.3% | −1.5±5.2% | 5.4±8.5% |
| RT | 49.7±19.1 | 47.3±17.2 | 45.8±15.5 | −4.8±3.2% | −3.2±7.4% | −7.8±6.2% |
| AART | 42.5±12.5 | 40.1±11.9 | 39.4±12.1 | −5.6±6.6% | −1.7±5.6% | −7.3±7.8% |
| P value, time-by-group interactions: | 0.09 | 0.11 | 0.05 | |||
Data are means ± SD; n = 7 for AA group, n = 12 for group, and n = 12 for AART group. See Table 1 for description of study groups. DXA, dual X-ray absorptiometry, CT, computerized tomography. P values shown represent time-by-group interactions for comparisons between end of bed rest and baseline, end of recovery and end of bed rest, end of recovery and baseline, as determined by repeated measures ANOVA with energy intake as a covariate.