***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: OBJECTIVE Changing dietary and physical activity habits has the potential to postpone or prevent the development of type 2 diabetes . However , it needs to be assessed whether moderate interventions , in agreement with current guidelines for the general population , are effective . We evaluated the impact of a 2-year combined diet and physical activity intervention program on glucose tolerance in Dutch subjects at increased risk for developing diabetes . RESEARCH METHODS AND PROCEDURES Subjects with glucose intolerance were r and omly assigned to either the lifestyle intervention group ( INT ) or control group ( CON ) . The INT received regular dietary advice and was stimulated to increase their physical activity . The CON received a brief leaflet about healthy diet and increased physical activity . Primary outcome measure was the change in glucose tolerance . RESULTS In total , 88 subjects completed 2 years of intervention ( 40 subjects in the INT , 48 subjects in the CON , mean BMI 29.4 kg/m2 ) . Subjects in the INT reduced their body weight , waist circumference , and ( saturated ) fat intake and improved their aerobic capacity . Two-hour plasma glucose concentration declined from 8.7 to 8.0 mM in the INT and rose from 8.6 to 9.4 mM in the CON ( p < 0.01 ) . Subjects adherent to both the diet and exercise intervention showed the largest reduction in 2-hour glucose levels . DISCUSSION Our results showed that a lifestyle intervention program according to general recommendations improves glucose tolerance , even in a less obese and more physical active population . Furthermore , our results underscore the importance of combining diet and physical activity to improve glucose tolerance and insulin resistance Lifestyle modification reduces the risk of developing type 2 diabetes and may have its effect through improving insulin sensitivity , beta-cell function , or both . To determine whether diet and exercise improve insulin sensitivity and /or beta-cell function and to evaluate these effects over time , we quantified insulin sensitivity and the acute insulin response to glucose ( AIRg ) in 62 Japanese Americans ( age 56.5 + /- 1.3 years ; mean + /- SE ) with impaired glucose tolerance ( IGT ) who were r and omized to the American Heart Association ( AHA ) Step 2 diet plus endurance exercise ( n = 30 ) versus the AHA Step 1 diet plus stretching  ( n = 32 ) for 24 months . beta-Cell function ( disposition index [ DI ] ) was calculated as S(i ) x AIRg , where S(i ) is the insulin sensitivity index . The incremental area under the curve for glucose ( incAUCg ) was calculated from a 75-g oral glucose tolerance test . Intra-abdominal fat ( IAF ) and subcutaneous fat ( SCF ) areas were measured by computed tomography . At 24 months , the Step 2/endurance group had lower weight ( 63.1 + /- 2.4 vs. 71.3 + /- 2.9 kg ; P = 0.004 ) and IAF ( 75.0 + /- 7.9 vs. 112.7 + /- 10.4 cm(2 ) ; P = 0.03 ) and SCF ( 196.5 + /- 18.0 vs. 227.7 + /- 19.9 cm(2 ) ; P < 0.001 ) areas , greater S(i ) ( 4.7 + /- 0.5 vs. 3.3 + /- 0.3 x 10(-5 ) min . pmol(-1 ) . l(-1 ) ; P = 0.01 ) , and a trend toward lower AIRg ( 294.9 + /- 50.0 vs. 305.4 + /- 30.0 pmol/l ; P = 0.06 ) and incAUCg ( 8,217.3 + /- 350.7 vs. 8,902.0 + /- 367.2 mg . dl(-1 ) . 2 h(-1 ) ; P = 0.08 ) compared with the Step 1/stretching group after adjusting for baseline values . There was no difference in the DI ( P = 0.7 ) between the groups . S(i ) was associated with changes in weight ( r = -0.426 , P = 0.001 ) and IAF ( r = -0.395 , P = 0.003 ) and SCF ( r = -0.341 , P = 0.01 ) areas . Thus , the lifestyle modifications decreased weight and central adiposity and improved insulin sensitivity in Japanese Americans with IGT . However , such changes did not improve beta-cell function , suggesting that this degree of lifestyle modifications may be limited in preventing type 2 diabetes over the long term Prevention of type 2 diabetes by intensive lifestyle intervention design ed to achieve and maintain ideal body weight was assessed in subjects with impaired glucose tolerance ( IGT ) . Male subjects with IGT recruited from health-screening examinees were r and omly assigned in a 4:1 ratio to a st and ard intervention group ( control group ) and intensive intervention group ( intervention group ) . The final numbers of subjects were 356 and 102 , respectively . The subjects in the control group and in the intervention group were advised to maintain body mass index ( BMI ) of < 24.0 kg/m2 and of < 22.0 kg/m2 , respectively , by diet and exercise . In the intervention group , detailed instructions on lifestyle were repeated every 3 - 4 months during hospital visits . Diabetes was judged to have developed when two or more consecutive fasting plasma glucose ( FPG ) values exceeded 140 mg/dl . A 100 g oral glucose tolerance test was performed every 6 months to detect improvement of glucose tolerance . The subjects were seen in an ordinary outpatient clinic . The cumulative 4-year incidence of diabetes was 9.3 % in the control group , versus 3.0 % in the intervention group , and the reduction in risk of diabetes was 67.4 % ( P < 0.001 ) . Body weight decreased by 0.39 kg in the control group and by 2.18 kg in the intervention group ( P < 0.001 ) . The control group was subclassified according to increase and decrease in body weight . The incidence of diabetes was positively correlated with the changes in body weight , and the improvement in glucose tolerance was negatively correlated . Subjects with higher FPG at baseline developed diabetes at a higher rate than those with lower FPG . Higher 2h plasma glucose values and higher BMI values at baseline were also associated with a higher incidence of diabetes , but the differences were not significant . Subjects with a low insulinogenic index ( DeltaIRI/DeltaPG 30 min after an oral glucose load ) developed diabetes at a significantly higher rate than those with a normal insulinogenic index . Comparison of the BMI data and incidence of diabetes in five diabetes prevention studies by lifestyle intervention revealed a linear correlation between the incidence of diabetes and the BMI values , with the exception of the DaQing Study . However , the slope of the reduction in incidence of diabetes in the intensive intervention groups was steeper than expected simply on the basis of the reduction of BMI , suggesting that the effect of lifestyle intervention can not be solely ascribed to the body weight reduction . We conclude that lifestyle intervention aim ed at achieving ideal body weight in men with IGT  is effective and can be conducted in an outpatient clinic setting Risk factors associated with the progression from impaired glucose tolerance ( IGT ) to NIDDM were examined in data from six prospect i ve studies . IGT and NIDDM were defined in all studies by World Health Organization ( WHO ) criteria , and baseline risk factors were measured at the time of first recognition of IGT . The studies varied in size from 177 to 693 participants with IGT , and included men and women followed from 2 to 27 years after the recognition of IGT . Across the six studies , the incidence rate of NIDDM was 57.2/1,000 person-years and ranged from 35.8/1,000 to 87.3/1,000 person-years . Although baseline measures of fasting and 2-h postchallenge glucose levels were both positively associated with NIDDM incidence , incidence rates were sharply higher for those in the top quartile of fasting plasma glucose levels , but increased linearly with increasing 2-h postchallenge glucose quartiles . Incidence rates were higher among the Hispanic , Mexican-American , Pima , and Nauruan population s than among Caucasians . The effect of baseline age on NIDDM incidence rates differed among the studies ; the rates did not increase or rose only slightly with increasing baseline age in three of the studies and formed an inverted U in three studies . In all studies , estimates of obesity ( including BMI , waist-to-hip ratio , and waist circumference ) were positively associated with NIDDM incidence . BMI was associated with NIDDM incidence independently of fasting and 2-h post challenge glucose levels in the combined analysis of all six studies and in three cohorts separately , but not in the three studies with the highest NIDDM incidence rates . Sex and family history of diabetes were generally not related to NIDDM progression . This analysis indicates that persons with IGT are at high risk and that further refinement of risk can be made by other simple measurements . The ability to identify persons at high risk of NIDDM should facilitate clinical trials in diabetes prevention The aim of the Finnish Diabetes Prevention Study is to assess the efficacy of an intensive diet-exercise programme in preventing or delaying  type 2 diabetes in individuals with impaired glucose tolerance ( IGT ) and to evaluate the effect of the programme on the risk factors of atherosclerotic vascular diseases and the incidence of cardiovascular events . In this ongoing study , a total of 523 overweight subjects with IGT based on two oral glucose tolerance tests were r and omized to either an intervention group or a control group . The main measure in the intervention group is individual dietary advice aim ed at reducing weight and intake of saturated fat and increasing intake of dietary fibre . The intervention subjects are individually guided to increase their level of physical activity .  The control group receives general information about the benefits of weight reduction , physical activity and healthy diet in the prevention of diabetes . A pilot study began in 1993 , and recruitment ended in 1998 . By the end of April 1999 there were 65 new cases of diabetes , 34 drop-outs and one death . The weight reduction was greater ( -4.6 kg ) at 1 year in the intervention group ( n = 152 ) than in the control group ( n = 143 , -0.9 kg , P < 0.0001 ) , and this difference was sustained in the second year of follow-up . At 1 year 43.4 % and at 2 years 41.8 % of the intervention subjects had achieved a weight reduction of at least 5 kg , while the corresponding figures for the control subjects were 14.0 and 12.0 % ( P < 0.001 between the groups ) . At 1 year the intervention group showed significantly greater reductions in 2 h glucose , fasting and 2 h insulin , systolic and diastolic blood pressure , and serum triglycerides . Most of the beneficial changes in cardiovascular risk factors were sustained for 2 years . These interim results of the ongoing Finnish Diabetes Prevention Study demonstrate the efficacy and feasibility of the lifestyle intervention programme OBJECTIVE To describe the 1 ) lifestyle intervention used in the Finnish Diabetes Prevention Study , 2 ) short- and long-term changes in diet and exercise behavior , and 3 ) effect of the intervention on glucose and lipid metabolism . RESEARCH DESIGN AND METHODS There were 522 middle-aged , overweight subjects with impaired glucose tolerance who were r and omized to either a usual care control group or an intensive lifestyle intervention group .  The control group received general dietary and exercise advice at baseline and had an annual physician 's examination . The subjects in the intervention group received additional individualized dietary counseling from a nutritionist . They were also offered circuit-type resistance training sessions and advised to increase overall physical activity .  The intervention was the most intensive during the first year , followed by a maintenance period . The intervention goals were to reduce body weight , reduce dietary and saturated fat , and increase physical activity and dietary fiber . RESULTS The intervention group showed significantly greater improvement in each intervention goal . After 1 and 3 years , weight reductions were 4.5 and 3.5 kg in the intervention group and 1.0 and 0.9 kg in the control group , respectively . Measures of glycemia and lipemia improved more in the intervention group . CONCLUSIONS The intensive lifestyle intervention produced long-term beneficial changes in diet , physical activity , and clinical and biochemical parameters and reduced diabetes risk . This type of intervention is a feasible option to prevent type 2 diabetes and should be implemented in the primary health care system Clinical trials have demonstrated that lifestyle changes can prevent type 2 diabetes , but the importance of leisure-time physical activity ( LTPA ) is still unclear . We carried out post hoc analyses on the role of LTPA in preventing type 2 diabetes in 487 men and women with impaired glucose tolerance who had completed 12-month LTPA question naires . The subjects were participants in the Finnish Diabetes Prevention Study , a r and omized controlled trial of lifestyle changes including diet , weight loss , and LTPA .  There were 107 new cases of diabetes during the 4.1-year 
    Output:
    
In the four studies that measured the incidence of diabetes as an outcome , the risk of diabetes was reduced by approximately 50 % ( range 42–63 % ) ; as these studies reported only small changes in physical activity levels , the reduced risk of diabetes is likely to be attributable to factors other than physical activity .
These results indicate that the contribution of physical activity independent of dietary or weight loss changes to the prevention of type 2 diabetes in people with prediabetes is equivocal