MUSCLE STRENGTH, GH AND IGF-1 IN OLDER WOMEN SUBMITTED TO LAND AND AQUATIC RESISTANCE TRAINING

Abstract

ABSTRACT Introduction: Aging leads to decline in multiple organ systems associated to hormone alterations and loss of muscle mass and strength. Objective: To evaluate the effects of land and water resistance training on muscle strength, basal serum levels of GH, IGF-1, and IGFBP3 in elderly women. Methods: Subjects were distributed in three groups: land resistance training (LRT; n=10; age: 66.10±2.77 years), water resistance training (WRT; n=10; age: 67.10±3.54 years) and control (CG; n=10; age: 68.80±5.41 years). Muscle strength was assessed with the 1-RM test in bench press (BP) and leg press (LP) exercises. Serum levels of GH, IGF-1, and IGFBP3 were analyzed by chemiluminescence. Results: Repeated measures ANOVA showed elevated muscle strength in the BP only in LRT (D%=60.2%; p=0.0001) when compared to the CG (D%=46.73%, p=0.0001) and WRT (D%=32.49%, p=0.004). LRT and WRT increased muscle strength in LP (D%LRT=57.14%; p=0.004; D%WRT=42.3%; p=0.033). There was an increase in LRT and WRT in the LP when compared to CG (D%=45.59%, p=0.019; D%=43.97%, p=0.026, respectively). IGF-1 was elevated only in LRT (D%=49.72%, p=0.004) from pre- to post-test and when compared to WRT (D%=56.76%, p=0.002) and CG (D%=74.63%, p=0.0001). IGFBP3 levels showed that only WRT increased (D%=26.79%, p=0.044) from pre- to post-test. The IGF-1/IGFBP3 ratio demonstrated that LRT reached intragroup elevation (D%=52.66%, p=0.002) and when compared to WRT (D%=94.11%, p=0.0001) and CG (D%=73.45%, p=0.0001). There was no significant difference in GH. Conclusion: Land resistance training may provide better anabolic effects in elderly women.