Table 3.
Indices of glucose tolerance and insulin action before and after intervention.
| EX (n = 18b) | CR (n = 18) | HL (n = 10) | Among group P | |
|---|---|---|---|---|
| ISI a | ||||
| Baseline | 4.5 ± 2.3 | 7.7 ± 4.8 | 4.2 ± 2.8 | |
| Final | 7.4 ± 2.9† | 9.7 ± 3.7† | 4.5 ± 2.9 | 0.001 |
| Change | 3.0 ± 2.7* | 2.0 ± 3.9* | 0.3 ± 1.4 | |
| Fasting insulin, μU/mL a | ||||
| Baseline | 8.2 ± 4.7 | 6.8 ± 6.1 | 9.0 ± 3.4 | |
| Final | 5.6 ± 3.7† | 4.4 ± 2.8† | 10.3 ± 5.3 | 0.01 |
| Change | −2.7 ± 5.0* | −2.5 ± 3.9* | 1.3 ± 3.2 | |
| Insulin AUC, ×103 min·μU/mL | ||||
| Baseline | 9.1 ± 4.5 | 5.5 ± 2.9 | 10.2 ± 4.7 | |
| Final | 5.7 ± 2.9† | 4.2 ± 1.5† | 8.8 ± 3.6 | 0.001 |
| Change | −3.4 ± 3.0* | −1.3 ± 2.1* | −1.4 ± 2.1 | |
| Fasting glucose, mg/dL | ||||
| Baseline | 96.1 ± 5.8 | 94.7 ± 8.7 | 94.0 ± 9.2 | |
| Final | 94.7 ± 6.4 | 89.4 ± 7.3 | 92.1 ± 10.4 | 0.06 |
| Change | −1.4 ± 4.6 | −5.3 ± 6.3 | −1.9 ± 6.5 | |
| Glucose AUC, ×103 min·mg/dL | ||||
| Baseline | 18.4 ± 2.5 | 18.4 ± 3.4 | 17.6 ± 3.4 | |
| Final | 16.0 ± 1.9 | 15.9 ± 2.2 | 16.9 ± 3.0 | 0.11c |
| Change | −2.4 ± 2.5 | −2.5 ± 2.5 | −0.7 ± 1.5 | |
P ≤ 0.05 for within group change by paired t-test.
P ≤ 0.05 versus HL group for baseline-adjusted final values by ANCOVA and Tukey tests. ANOVA indicated significant differences among groups for baseline ISI, however, post-hoc Tukey tests were only marginally significant for EX versus CR and HL versus CR (both p=0.06) and not significant for EX versus HL. Baseline insulin AUC was significantly different for EX versus CR and HL versus CR by ANOVA and Tukey tests. None of the other outcomes were different among groups at baseline according to ANOVA. “Among group P” reflects the significance of the among-group differences in final values for each outcome after adjustment for baseline values using ANCOVA. Data are arithmetic means ± SD.
Data were log transformed for data analyses.
Non-fasting insulin data are missing for one participant due to technical errors during data collection.
Addition of baseline ISI as a covariate resulted in a significant among-group effect (p=0.03) and post-hoc Tukey tests revealed significant differences in final adjusted glucose AUC values for EX versus HL and CR versus HL; the within-group decreases in glucose AUC were significant (P ≤ 0.05) in the EX and HL groups by paired t-test. ISI, insulin sensitivity index determined according to Matsuda and DeFronzo (13); AUC, total area under the curve.