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Objective: To study the associations of objectively measured physical activity (PA) and sedentary time (ST) with the combined outcome of incident stroke, myocardial infarction (MI) or all-cause mortality in older adults.

Methods: N = 3343 men and women aged 70 who participated in a health survey between 2012 and 2017 were included. Actigraph GT3X+ accelerometers were used to measure light-intensity PA (LPA), moderate-intensity PA (MPA) and ST for 1 week. Incident cases of cardiovascular disease (CVD) in terms of stroke or MI, and all-cause mortality were identified using national registers. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated using multivariable-adjusted Cox regressions.

Results: During a mean follow-up of 2.7 years (0.1–5.6), there were 124 events of CVD or all-cause mortality. After adjusting for potential confounders and mediators, every 30-min/day increment in LPA was associated with 11% lower risk of CVD or all-cause mortality (HR 0.89, 95% CI 0.82–0.97), and every 30-min/day increment in MPA was associated with 36% lower risk (HR 0.64, 95% CI 0.48–0.84). Every 1-h/day increment in ST increased the risk of the outcomes by 33% (HR 1.33, 95% CI 1.14–1.56), although there was no significant association among participants who performed ≥ 30 min/day MPA (HR 1.11, 95% CI 0.82–1.50, P = 0.034 for interaction). None of the associations were modified by sex (P > 0.4 for all).

Conclusion: Objectively measured LPA and MPA are each associated with lower risk of stroke, MI or all-cause mortality in 70-year-old individuals, while ST is associated with increased risk. The greatest risk reduction is observed for MPA, which also appears to attenuate some of the increased risks associated with ST.

BACKGROUND: Aging leads to increased visceral adipose tissue (VAT) and reduced skeletal muscle density. To which extent these are associated with the risk of stroke, myocardial infarction (MI), and all-cause mortality in older adults is unknown.

METHODS AND RESULTS: A total of 3294 70-year-old individuals (49.6% women) underwent a health examination in Umeå, Sweden, during 2012 to 2018. VAT and muscle density were measured using dual-energy x-ray absorptiometry and peripheral quantitative computed tomography. Cases of stroke, MI, and all-cause mortality were collected through national registers. Cox regressions were used to calculate hazard ratios (HRs) and 95% CIs per SD greater VAT and per SD lower muscle density. During a mean follow-up of 3.6 years, there were 108 cases of stroke or MI, and 97 deaths. Greater VAT (adjusted HR [aHR], 1.56; 95% CI, 1.09– 2.22), but not lower muscle density (aHR, 1.14; 95% CI, 0.97–1.34), was associated with increased risk of stroke or MI. Neither VAT (aHR, 0.95; 95% CI, 0.65–1.41) nor muscle density (aHR, 1.11; 95% CI, 0.92–1.34) was associated with all-cause mortality. The association of VAT with stroke or MI was only significant in men (aHR, 1.86; 95% CI, 1.19– 2.91) but not women (aHR, 0.60; 95% CI, 0.25–1.42) (Pinteraction =0.038).

CONCLUSIONS: With the limitation of being an observational study, these findings suggest that VAT is an important obesity-related predictor of cardiovascular risk in 70-year-old men, and by implication, that decreasing VAT may potentially reduce their risk of cardiovascular disease.

OBJECTIVE: To investigate the effects of 10 weeks of progressive vigorous-intensity interval training as a single intervention on body composition among 70-year-old individuals with central obesity.

DESIGN: Randomized controlled trial (ClinicalTrials.gov registration No. NCT03450655).

SETTING: Community-dwelling 70-year-old men and women living in the Umeå municipality in Sweden.

PARTICIPANTS: Seventy-seven 70-year-old men and women with central obesity (greater than 1 kg visceral adipose tissue [VAT] for women and greater than 2 kg VAT for men).

INTERVENTION: Participants allocated to the intervention group were offered a 10-week progressive concurrent exercise program performed three times per week. All participants in both groups had received tailored lifestyle recommendations focused on diet and physical activity at one occasion within 12 months prior to trial initiation.

MEASUREMENTS: The primary outcome was changes in VAT, and secondary outcomes included changes in total fat mass (FM), total lean body mass (LBM), and body mass index.

RESULTS: Comparing the groups, there were no significant differences in decrease of VAT mass (P = .10), although the intervention group significantly decreased FM by 716 g (P = .01) and gained LBM by 508 g (P = .03), compared to the control group. Furthermore, the effects of the training were significantly greater in the male subcohort (P < .05 for interaction), with positive effects also on VAT and FM, where men in the intervention group decreased VAT by 175 g (P < .05) and FM by 1364 g (P = .004), compared to the male controls.

CONCLUSIONS: The present trial demonstrates that 10 weeks of progressive vigorous interval training is sufficient to significantly decrease FM in older adults with central obesity, with positive effects also on LBM.

Observational studies show that physical activity is strongly associated with a reduced risk of premature mortality and major non-communicable diseases. We reviewed to which extent these associations have been confirmed in randomized controlled trials (RCTs) for the outcomes of mortality, cardiovascular disease (CVD), type 2 diabetes (T2D), and fracture. The results show that exercise does not reduce all-cause mortality and incident CVD in older adults or in people with chronic conditions, based on RCTs comprising ∼50,000 participants. The results also indicate a lack of effect on cardiovascular mortality in people with chronic conditions, based on RCTs comprising ∼11,000 participants. Furthermore, there is inconsistent evidence regarding the effect of exercise on fractures in older adults, based on RCTs comprising ∼40,000 participants. Finally, based on RCTs comprising ∼17,000 participants, exercise reduces T2D incidence in people with prediabetes when combined with dietary modification, although evidence for the individual effect of exercise is lacking. Identified shortcomings of the current evidence include risks of publication bias, lack of high-quality studies in certain high-risk populations, and inconstant evidence with respect to some outcomes. Thus, additional large trials would be of value, especially with fracture as the primary outcome. In conclusion, according to current RCT evidence, exercise can prevent T2D assuming it is combined with dietary intervention. However, the current evidence shows that exercise does not prevent premature mortality or CVD, with inconsistent evidence for fractures.