Silvano Zanuso

Anti-inflammatory effect of exercise training in subjects with type 2 diabetes and the metabolic syndrome is dependent on exercise modalities and independent of weight loss

BACKGROUND AND AIMS We investigated the effect of different exercise modalities on high sensitivity-C reactive protein (hs-CRP) and other inflammatory markers in patients with type 2 diabetes and the metabolic syndrome. METHODS AND RESULTS Eighty-two patients were randomized into 4 groups: sedentary control (A); receiving counseling to perform low-intensity physical activity (B); performing prescribed and supervised high-intensity aerobic (C) or aerobic+resistance (D) exercise (with the same caloric expenditure) for 12 months. Evaluation of leisure-time physical activity and assessment of physical fitness, cardiovascular risk factors and inflammatory biomarkers was performed at baseline and every 3 months. Volume of physical activity increased and HbA(1c) decreased in Groups B-D. VO(2max), HOMA-IR index, HDL-cholesterol, waist circumference and albuminuria improved in Groups C and D, whereas strength and flexibility improved only in Group D. Levels of hs-CRP decreased in all three exercising groups, but the reduction was significant only in Groups C and D, and particularly in Group D. Changes in VO(2max) and the exercise modalities were strong predictors of hs-CRP reduction, independent of body weight. Leptin, resistin and interleukin-6 decreased, whereas adiponectin increased in Groups C and D. Interleukin-1β, tumor necrosis factor-α and interferon-γ decreased, whereas anti-inflammatory interleukin-4 and 10 increased only in Group D. CONCLUSION Physical exercise in type 2 diabetic patients with the metabolic syndrome is associated with a significant reduction of hs-CRP and other inflammatory and insulin resistance biomarkers, independent of weight loss. Long-term high-intensity (preferably mixed) training, in addition to daytime physical activity, is required to obtain a significant anti-inflammatory effect.

Effect of an Intensive Exercise Intervention Strategy on Modifiable Cardiovascular Risk Factors in Subjects With Type 2 Diabetes Mellitus A Randomized Controlled Trial: The Italian Diabetes and Exercise Study (IDES)

BACKGROUND This study aimed to assess the efficacy of an intensive exercise intervention strategy in promoting physical activity (PA) and improving hemoglobin A(1c)(HbA(1c)) level and other modifiable cardiovascular risk factors in patients with type 2 diabetes mellitus (T2DM). METHODS Of 691 eligible sedentary patients with T2DM and the metabolic syndrome, 606 were enrolled in 22 outpatient diabetes clinics across Italy and randomized by center, age, and diabetes treatment to twice-a-week supervised aerobic and resistance training plus structured exercise counseling (exercise group) vs counseling alone (control group) for 12 months. End points included HbA(1c) level (primary) and other cardiovascular risk factors and coronary heart disease risk scores (secondary). RESULTS The mean (SD) volume of PA (metabolic equivalent hours per week) was significantly higher (P < .001) in the exercise (total PA [nonsupervised conditioning PA + supervised PA], 20.0 [0.9], and nonsupervised, 12.4 [7.4]) vs control (10.0 [8.7]) group. Compared with the control group, supervised exercise produced significant improvements (mean difference [95% confidence interval]) in physical fitness; HbA(1c) level (-0.30% [-0.49% to -0.10%]; P < .001); systolic (-4.2 mm Hg [-6.9 to -1.6 mm Hg]; P = .002) and diastolic (-1.7 mm Hg [-3.3 to -1.1 mm Hg]; P = .03) blood pressure; high-density lipoprotein (3.7 mg/dL [2.2 to 5.3 mg/dL]; P < .001) and low-density lipoprotein (-9.6 mg/dL [-15.9 to -3.3 mg/dL]; P = .003) cholesterol level; waist circumference (-3.6 cm [-4.4 to -2.9 cm]; P < .001); body mass index; insulin resistance; inflammation; and risk scores. These parameters improved only marginally in controls. CONCLUSIONS This exercise intervention strategy was effective in promoting PA and improving HbA(1c) and cardiovascular risk profile. Conversely, counseling alone, though successful in achieving the currently recommended amount of activity, was of limited efficacy on cardiovascular risk factors, suggesting the need for a larger volume of PA in these high-risk subjects. Trial Registration isrctn.org Identifier: ISRCTN04252749.

Exercise for the management of type 2 diabetes: a review of the evidence

The aim is to critically review the more relevant evidence on the interrelationships between exercise and metabolic outcomes. The research questions addressed in the recent specific literature with the most relevant randomized controlled trials, meta-analysis and cohort studies are presented in three domains: aerobic exercise, resistance exercise, combined aerobic and resistance exercise. From this review appear that the effects of aerobic exercise are well established, and interventions with more vigorous aerobic exercise programs resulted in greater reductions in HbA1c, greater increase in VO2max and greater increase in insulin sensitivity. Considering the available evidence, it appears that resistance training could be an effective intervention to help glycemic control, especially considering that the effects of this form of intervention are comparable with what reported with aerobic exercise. Less studies have investigated whether combined resistance and aerobic training offers a synergistic and incremental effect on glycemic control; however, from the available evidences appear that combined exercise training seems to determine additional change in HbA1c that can be seen significant if compared with aerobic training alone and resistance training alone.

Changes in insulin sensitivity in response to different modalities of exercise: a review of the evidence

Type 2 diabetes is an increasingly prevalent condition with complications including blindness and kidney failure. Evidence suggests that type 2 diabetes is associated with a sedentary lifestyle, with physical activity demonstrated to increase glucose uptake and improve glycaemic control. Proposed mechanisms for these effects include the maintenance and improvement of insulin sensitivity via increased glucose transporter type four production. The optimal mode, frequency, intensity and duration of exercise for the improvement of insulin sensitivity are however yet to be identified. We review the evidence from 34 published studies addressing the effects on glycaemic control and insulin sensitivity of aerobic exercise, resistance training and both combined. Effect sizes and confidence intervals are reported for each intervention and meta‐analysis presented. The quality of the evidence is tentatively graded, and recommendations for best practice proposed.

Effect of high- versus low-intensity supervised aerobic and resistance training on modifiable cardiovascular risk factors in type 2 diabetes; the Italian Diabetes and Exercise Study (IDES).

Background While current recommendations on exercise type and volume have strong experimental bases, there is no clear evidence from large-sized studies indicating whether increasing training intensity provides additional benefits to subjects with type 2 diabetes. Objective To compare the effects of moderate-to-high intensity (HI) versus low-to-moderate intensity (LI) training of equal energy cost, i.e. exercise volume, on modifiable cardiovascular risk factors. Design Pre-specified sub-analysis of the Italian Diabetes and Exercise Study (IDES), a randomized multicenter prospective trial comparing a supervised exercise intervention with standard care for 12 months (2005–2006). Setting Twenty-two outpatient diabetes clinics across Italy. Patients Sedentary patients with type 2 diabetes assigned to twice-a-week supervised progressive aerobic and resistance training plus exercise counseling (n = 303). Interventions Subjects were randomized by center to LI (n = 142, 136 completed) or HI (n = 161, 152 completed) progressive aerobic and resistance training, i.e. at 55% or 70% of predicted maximal oxygen consumption and at 60% or 80% of predicted 1-Repetition Maximum, respectively, of equal volume. Main Outcome Measure(s) Hemoglobin (Hb) A1c and other cardiovascular risk factors; 10-year coronary heart disease (CHD) risk scores. Results Volume of physical activity, both supervised and non-supervised, was similar in LI and HI participants. Compared with LI training, HI training produced only clinically marginal, though statistically significant, improvements in HbA1c (mean difference −0.17% [95% confidence interval −0.44,0.10], P = 0.03), triglycerides (−0.12 mmol/l [−0.34,0.10], P = 0.02) and total cholesterol (−0.24 mmol/l [−0.46, −0.01], P = 0.04), but not in other risk factors and CHD risk scores. However, intensity was not an independent predictor of reduction of any of these parameters. Adverse event rate was similar in HI and LI subjects. Conclusions Data from the large IDES cohort indicate that, in low-fitness individuals such as sedentary subjects with type 2 diabetes, increasing exercise intensity is not harmful, but does not provide additional benefits on cardiovascular risk factors. Trial Registration www.ISRCTN.org ISRCTN-04252749.

Changes in physical fitness predict improvements in modifiable cardiovascular risk factors independently of body weight loss in subjects with type 2 diabetes participating in the Italian Diabetes and Exercise Study (IDES).

OBJECTIVE Physical fitness is inversely related to mortality in the general population and in subjects with type 2 diabetes. Here, we present data concerning the relationship between changes in physical fitness and modifiable cardiovascular risk factors in subjects with type 2 diabetes from the Italian Diabetes and Exercise Study. RESEARCH DESIGN AND METHODS Sedentary patients with type 2 diabetes (n = 606) were enrolled in 22 outpatient diabetes clinics and randomized to twice-a-week supervised aerobic and resistance training plus exercise counseling versus counseling alone for 12 months. Baseline to end-of-study changes in cardiorespiratory fitness, strength, and flexibility, as assessed by Vo2max estimation, a 5–8 maximal repetition test, and a hip/trunk flexibility test, respectively, were calculated in the whole cohort, and multiple regression analyses were applied to assess the relationship with cardiovascular risk factors. RESULTS Changes in Vo2max, upper and lower body strength, and flexibility were significantly associated with the variation in the volume of physical activity, HbA1c, BMI, waist circumference, high-sensitivity C-reactive protein (hs-CRP), coronary heart disease (CHD) risk score, and inversely, HDL cholesterol. Changes in fitness predicted improvements in HbA1c, waist circumference, HDL cholesterol, hs-CRP, and CHD risk score, independent of study arm, BMI, and in case of strength, also waist circumference. CONCLUSIONS Physical activity/exercise-induced increases in fitness, particularly muscular, predict improvements in cardiovascular risk factors in subjects with type 2 diabetes independently of weight loss, thus indicating the need for targeting fitness in these individuals, particularly in subjects who struggle to lose weight.

Is water-based exercise training sufficient to improve physical fitness in the elderly?

The research on the effects of aquatic exercise is a field that has grown rapidly in the last decade. The majority of the available literature is focused on the benefits of water-based exercise programs for people with rheumatologic disease and back pain; however, there is a lack of evidence reporting the effects of exercise performed in an aquatic medium for healthy elderly adults. The purpose of this study was to critically review the existing evidence of a potential relationship between water-based exercise and improvement of physical fitness in healthy elderly subjects. A systematic database search for manuscripts and a quality control were performed. A system of rating was defined. Aerobic, muscular strength, flexibility and body composition outcomes were then extracted. Nine studies were analyzed after the screening for eligibility: five randomized controlled trials (RCT), three randomized uncontrolled trials (UT) and one controlled trial (CT). Four RCT and two randomized UT were classified as high quality studies. One RCT, one randomized UT and one CT were considered low quality studies. Strong evidence supports the use of water-based exercise for the improvement of aerobic capacity and strength. Moderate evidence highlights the benefits on flexibility, and inconclusive evidence was found supporting the modification of body composition.

Physical activity, a key factor to quality of life in type 2 diabetic patients

Exercise as a public health tool has largely been built around its plausible impact on physical health, including a positive impact on the prevention and management of type 2 diabetes. There is a growing interest in its potential to influence other aspects of quality of life such as mental health and general well‐being. The effects of physical activity on overall quality of life are well established in the general population and have been analyzed on various dimensions of the Health‐Related Quality of Life (HRQL) including physical and social functioning; subjective well‐being, emotion and mood; self esteem and self‐perception; cognitive performance; and sleep quality.

Correlates of muscle strength in diabetes The study on the assessment of determinants of muscle and bone strength abnormalities in diabetes (SAMBA)

BACKGROUND AND AIMS Apart from late motor nerve dysfunction, factors affecting muscle strength in diabetes are largely unknown. This study was aimed at assessing muscle strength correlates in diabetic subjects encompassing a wide range of peripheral nerve function and various degrees of micro and macrovascular complications. METHODS AND RESULTS Four-hundred consecutive patients with type 1 and 2 diabetes (aged 46.4 ± 13.9 and 65.8 ± 10.3 years, respectively) from the Study on the Assessment of Determinants of Muscle and Bone Strength Abnormalities in Diabetes (SAMBA) were examined for upper and lower body muscle isometric maximal voluntary contraction by dynamometry. Univariate and multivariate regression analyses were applied to identify strength correlates. Isometric force at both the upper and lower limbs was significantly lower in subjects with than in those without any complication. At univariate analysis, it was strongly associated with age, diabetes duration, physical activity (PA) level, cardio-respiratory fitness, anthropometric parameters, surrogate measures of complications, and parameters of sensory and autonomic, but not motor (except amplitude) neuropathy. Multivariate analysis revealed that upper and lower body strength correlated independently with male gender and, inversely, with age, autonomic neuropathy score (or individual autonomic function abnormalities), and vibration perception threshold, but not sensory-motor neuropathy score. Diabetes duration and PA level were excluded from the model. CONCLUSIONS Both upper and lower body muscle strength correlate with measures of diabetic complications and particularly with parameters of sensory and especially autonomic nerve function, independently of diabetes duration and PA level, thus suggesting the involvement of mechanisms other than manifest motor nerve impairment.

Improvement of quality of life with supervised exercise training in subjects with type 2 diabetes mellitus

In the recent Italian Diabetes and Exercise Study (IDES),1 we showed that a strategy combining a prescribed and supervised mixed training program with structured exercise counseling is more effective than counseling alone in improving physical fitness, hemoglobin A1c level and other modifiable cardiovascular risk factors, and coronary heart disease 10-year risk scores in a large cohort of sedentary subjects with type 2 diabetes mellitus. In addition, subjects participating in the supervised sessions performed a higher volume of physical activity (PA) compared with the control group. However, long-term patient compliance with exercise recommendations is largely dependent on changes in quality of life (QoL) associated with training. Unfortunately, although increased PA is expected to improve QoL and most epidemiological studies have demonstrated an association between exercise and QoL in the general population, the very few intervention trials investigating the impact of structured exercise counseling or supervised training on physical and mental health and well-being in diabetic subjects have provided inconclusive results. We report herein data on the effect of supervised mixed exercise training on top of structured exercise counseling compared with counseling alone on QoL-related measures in subjects with type 2 diabetes participating in the IDES.