In Chinese type 2 diabetic patients, the WHO criterion has a better discriminative power over the NCEP criterion for predicting death. Among the various components of the MES defined either by WHO or NCEP, hypertension, albuminuria and low BMI were the main predictors of cardiovascular and total mortality.

Abdominal obesity and low cardiorespiratory fitness (CRF) are associated with insulin resistance in older adults. Exercise is associated with improvement in insulin sensitivity. Whether this association is mediated by change in CRF and/or abdominal obesity is unclear. The current study is a secondary analysis of data from a randomized controlled trial in Kingston, Ontario. Sedentary older adults (60–80 years) (N = 80) who completed the exercise (N = 59) or control (N = 21) conditions for 6 months were included. CRF was measured using a treadmill test, adipose tissue (AT) by magnetic resonance imaging, and insulin sensitivity by hyperinsulinemic-euglycemic clamp. Waist circumference (WC) was measured at the iliac crest. Mediation analyses were used to assess whether abdominal AT and/or CRF mediated the exercise-induced change in insulin sensitivity. By comparison to controls, reduction (mean ± SD) was observed for visceral (-0.4 ± 0.4 kg) and abdominal subcutaneous (-0.4 ± 0.4) AT depots, WC (-4.1 ± 3.2 cm) and BMI (-0.9 ± 0.8 kg/m2) (p < 0.05). Insulin sensitivity (4.2 ± 5.2 M/I) and CRF (0.2 ± 0.3 L/min) improved in the exercise group (p < 0.05). All AT variables, BMI and WC were mediators of the change in insulin sensitivity (p < 0.05). After adjustment for change in total AT, abdominal AT remained a mediator with an effect ratio of 0.79 (p < 0.05), whereas total AT was not significant when adjusted for abdominal AT (p > 0.05). The effect ratio for change in WC and BMI combined (0.63, p<0.05) was greater than either alone. In conclusion, CRF did not mediate the exercise-induced change in insulin sensitivity in older adults. Abdominal adiposity was a strong mediator independent of change in total adiposity.

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Although a majority of adults increase cardiorespiratory fitness (CRF; VO2 peak) in response to an increase in daily physical activity, the optimal exercise strategy for reversing low CRF is unknown. We performed a randomized, controlled trial designed to study the separate effects of habitual exercise differing in dose (energy expenditure, kcal/session) and intensity (relative to VO2max) on CRF. We randomly assigned sedentary, abdominally obese men and women to one of the following 4 conditions: 1) No-exercise control (C), 2) Low volume, low intensity exercise (LVLI: 180 [[female symbol]] and 300 [[male symbol]] kcal @ 50% VO2 peak), 3) High volume, low intensity exercise (HVLI: 360 [[female symbol]] and 600 [[male symbol]] kcal @ 50% VO2 peak), 4) High volume, high intensity (HVHI: 360 [[female symbol]] and 600 [[male symbol]] kcal @ 75% VO2 peak). All participants were required to exercise under supervision 5 times per week for 24 weeks. Adherence to exercise averaged 95% across groups. Exercise dose and intensity achieved was not different from that prescribed regardless of group. The minutes exercised per session were 30±7 in LVLI, 51±16 in HVLI and 36±11 in HVHI. A marked variability in CRF response to exercise was observed independent of group (Figure). Compared to controls, CRF increased within all exercise conditions (P<0.05). However, the CRF increase within the HVHI group (0.61±0.30L/min) was greater than both the HVLI (0.42±0.32L/min) and LVLI (0.26±0.28L/min) groups (P<0.05). Thus, despite matching exercise volume within the HVHI and HVLI groups, exercise at 75% of VO2peak was associated with a marked increase in CRF by compared to exercise at 50%. Given that the time required to achieve the energy expenditure within the HVHI group was 30% less than the HVLI group (36 vs 51 min), these findings have important implications for allied health professionals seeking options for prescribing exercise to improve a major risk factor for morbidity and mortality, cardiorespiratory fitness.