不同強度阻力運動訓練對高齡糖尿病前期族群胰島素敏感性的影響(II)

The purpose of the investigation was to examine the influence of resistance training (RT) with equal volume and varying load on insulin sensitivity, body composition, muscle quality, and physical function in older adults with prediabetes. Methods: Older men and women with prediabetes were recruited, then randomly assigned to HIGH (3 × 8 × 80% 1RM; n=10) or LOW (3 × 16 × 40% 1RM; n=10) group for 8 weeks of whole-body RT. The oral glucose tolerance test (OGTT), lipid profile, DEXA scan, functional capacity, and muscle function were measured at baseline and follow-up. Results: The OGTT area under the curve for glucose (-5.3%) decreased significantly in older adults with prediabetes after 8-weeks of volume-matched RT. HOMA-IR (-21.7%) decreased significantly and Matsuda Index (+25.0%) and Disposition Index (+54.6%) increased significantly after intervention (p < 0.05). No changes in lean body mass, body fat percentage, and lipid profile were observed after intervention (p > 0.05). Functional capacity and muscle quality (upper and lower limbs) increased significantly after intervention (p < 0.05). HIGH group had significant improvements in muscle strength of shoulder press (17.3 % vs 9.8%), seated row (23.7% vs 9.9%), and back extension (31.8% vs 12.7%) compared with LOW group (p < 0.05). Changes in 30-sec chair stand and timed up and go tests were inversely and positively correlated with changes in HOMA-IR (r = -0.480 and r = 0.529, p < 0.05). Conclusion: Results indicate that equal-volume RT at different loads is beneficial for insulin sensitivity, muscle quality, and physical function in older adults with prediabetes, and high-load RT results in greater muscular strength gains.