The effects of aerobic exercise on metabolic risk, insulin sensitivity and intrahepatic lipid in healthy older people from the Hertfordshire Cohort Study: a randomised controlled trial

Abstract

Aims/hypothesis We sought to determine the effect of an aerobic exercise intervention on clustered metabolic risk and related outcomes in healthy older adults in a singlecentre, explanatory randomised controlled trial. Methods Participants from the Hertfordshire Cohort Study (born 1931-1939) were randomly assigned to 36 supervised 1 h sessions on a cycle ergometer over 12 weeks or to a non-intervention control group. Randomisation and group allocation were conducted by the study co-ordinator, using a software programme. Those with prevalent diabetes, unstable ischaemic heart disease or poor mobility were excluded. All data were collected at our clinical research facility in Cambridge. Components of the metabolic syndrome were used to derive a standardised composite metabolic risk score (zMS) as the primary outcome. Trial status: closed to follow-up. Results We randomised 100 participants (50 to the intervention, 50 to the control group). Mean age was 71.4 (range 67.4-76.3) years. Overall, 96% of participants attended for follow-up measures. There were no serious adverse events. Using an intention-to-treat analysis, we saw a nonsignificant reduction in zMS in the exercise group compared with controls (0.07 [95% CI −0.03, 0.17], p=0.19). However, the exercise group had significantly decreased weight, waist circumference and intrahepatic lipid, with increased aerobic fitness and a 68% reduction in prevalence of abnormal glucose metabolism ], p=0.035) compared with controls. Results were similar in per-protocol analyses. Conclusions/interpretation Enrolment in a supervised aerobic exercise intervention led to weight loss, increased fitness and improvements in some but not all metabolic outcomes. In appropriately screened older individuals, such interventions appear to be safe.

Exercise and non-alcoholic fatty liver disease: A systematic review and meta-analysis

“…In contrast, a significant benefit on liver fat was apparent from the pooled data of the six studies (156 adults in total) which exclusively used exercise interventions vs. a nonexercise control. A similar benefit on liver fat has also been reported in adolescent populations [33] and in older adults [19], in studies which did not meet our inclusion criteria. Together, this suggests that the hepatic benefit of exercise applies across the lifespan.…”

“…Excluded from eligibility criteria n = 14 • Not adult (1) • Skewed data (1) • No/unsuitable control (9) • Insufficient data (2) Identified from reference search n = 2 study was removed from analysis due to skewed data [19]. After removal of duplicates and elimination of papers based on the eligibility criteria, 12 studies remained (Fig.…”

Effect of aerobic exercise training dose on liver fat and visceral adiposity

“…These studies employed exercise doses ranging from 2 to 6 days per week, lasting for 20-60 min per session, with intensities ranging between low (45% VO 2peak ) and strenuous (85% of VO 2peak ) [9,10,[16][17][18][19][20][21][22]. Therefore, establishing practical recommendations for exercise prescription is difficult based on the current evidence.…”

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

“…Comparable trials, where exercise programs induced substantial weight loss in postmenopausal women, suggest that weight loss is important for favorable effects on insulin resistance (15,16,18,21,(38)(39)(40). For example, in the NEW trial, effects of weight The b (95% CI) is the treatment effect ratio representing the overall intervention effect on metabolic variable (adjusted for baseline), including changes from baseline to 4 months and 4 to 12 months.…”