Effect of Exercise on Insulin Sensitivity in Healthy Postmenopausal Women: The SHAPE Study

Abstract

Background: An inactive lifestyle is a risk factor for several types of cancer. A proposed pathway through which exercise influences cancer risk is via insulin. We aim to investigate the effect of a oneyear exercise intervention on insulin sensitivity, and the role of body fat in this association, in healthy, normal to overweight/ obese, postmenopausal women.Methods: In the Sex Hormones And Physical Exercise (SHAPE) study, 189 healthy, inactive and postmenopausal women [ages, 50-69 years; body mass index (BMI), 22-40 kg/m 2 ] were randomly assigned to a one-year aerobic and strength exercise intervention (150 min/wk), or a control group. Between-group differences in fasting insulin, glucose, and homeostatic model assessment of insulin resistance (HOMA2) over time were estimated using linear mixed models.Results: Follow-up measurements of insulin sensitivity were available for 181 (95.8%) and 182 (96.3%) women at 4 and 12

The interaction effects of aerobic exercise training and vitamin D supplementation on plasma lipid profiles and insulin resistance in ovariectomized rats

“…These results suggest that vitamin D intake increases the sensitivity of insulin [73]. Although our previous studies [37,74] and others showed adequate effectiveness by regular physical activity in improving insulin resistance, OVX + AT + D showed a better response [43,75]. There are some mechanisms for the effects of vitamin D: the presence of vitamin D receptors on pancreatic β cells [76], Vitamin D-activating 1αhydroxylase is expressed in pancreatic β cells [77], the vitamin D response element in the insulin gene due to the presence of vitamin D receptors in skeletal muscle [78] and the fact that 1,25(OH)D increases the transcription of insulin receptor genes [79] and also suppresses the renin gene, reducing hyperglycemic-induced increases in renin levels in pancreatic β cells.…”

The interaction effects of aerobic exercise training and vitamin D supplementation on plasma lipid profiles and insulin resistance in ovariectomized rats

“…These results suggest that vitamin D intake increases the sensitivity of insulin [ 73 ]. Although our previous studies [ 37 , 74 ] and others showed adequate effectiveness by regular physical activity in improving insulin resistance, OVX + AT + D showed a better response [ 43 , 75 ]. There are some mechanisms for the effects of vitamin D: the presence of vitamin D receptors on pancreatic β cells [ 76 ], Vitamin D-activating 1αhydroxylase is expressed in pancreatic β cells [ 77 ], the vitamin D response element in the insulin gene due to the presence of vitamin D receptors in skeletal muscle [ 78 ] and the fact that 1,25(OH)D increases the transcription of insulin receptor genes [ 79 ] and also suppresses the renin gene, reducing hyperglycemic-induced increases in renin levels in pancreatic β cells.…”

Exercise and Cancer Prevention: Current Evidence and Future Directions

“…Mean attendance (or other adherence metrics) to the exercise prescription was not reported but it was stated that approximately 36% of subjects assigned to exercise therapy missed more than 30% of supervised sessions. For the primary end points, exercise did not confer a decrease in either circulating sex steroid hormones [50] or insulin sensitivity [30] compared to control.…”

“…In terms of circulating sex hormones, a factor investigated across all trials, ALPHA trial reported decreases in circulating estrogens (estradiol and free estradiol) [28] whereas non-significant declines were reported in PATH [46], SHAPE [50] and BETA [22]. For circulating insulin, decreases in insulin were observed in PATH [19] and ALPHA [24] trials but not SHAPE [30] and BETA [23], whereas circulating glucose was unchanged in all trials. For adiposity, reductions in total body fat was reported in all trials, favoring the exercise group [21,.…”