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OBJECTIVE In the Italian Diabetes and Exercise Study_2 (IDES_2), behavioral counseling promoted a sustained increase in physical activity (PA) volume (+3.3 MET h ⋅ week−1), moderate- to vigorous-intensity PA (MVPA) (+6.4 min ⋅ day−1), and light-intensity PA (LPA) (+0.8 h ⋅ day−1) and decrease in sedentary time (SED-time) (−0.8 h ⋅ day−1). Here, we investigated the relationships of changes in PA/SED-time with changes in physical fitness and cardiometabolic risk profile in individuals with type 2 diabetes. RESEARCH DESIGN AND METHODS In this 3-year randomized clinical trial, 300 physically inactive and sedentary patients were randomized 1:1 to receive 1-month theoretical and practical counseling once a year or standard care. Changes in physical fitness and cardiovascular risk factors/scores according to quartiles of accelerometer-measured changes in PA/SED-time were assessed, together with univariate and multivariable associations between these parameters, in the whole cohort and by study arm. RESULTS Physical fitness increased and HbA1c and coronary heart disease 10-year risk scores decreased with quartiles of MVPA and SED-time change. In quartile IV of MVPA increase and SED-time decrease, cardiorespiratory fitness increased by 5.23 and 4.49 mL ⋅ min−1 ⋅ kg−1 and HbA1c decreased by 0.73 and 0.85%, respectively. Univariate correlations confirmed these relationships, and mean changes in both MPVA and SED-time predicted changes in physical fitness and cardiovascular risk factors/scores independently of one another and of other confounders. Similar findings were observed with LPA and PA volume and in each group separately. CONCLUSIONS Even modest increments in MVPA may have a clinically meaningful impact, and reallocating SED-time to LPA may also contribute to improved outcomes, possibly by increasing total energy expenditure.

We read with great interest the results of the meta-analysis by Snowling and Hopkins (1) on the effects of different modes of exercise training on glucose control and risk factors for complications in type 2 diabetic patients. This most recent meta-analysis of post-2000 randomized controlled trials is perhaps most important because of the size of the cohort (over 1,000 type 2 diabetic patients) and for the study of characteristics and magnitude of effects in more detail than in the previous Boule meta-analyses (2). Snowling and Hopkins determined that an A1C reduction of 0.8 ± 0.3% is “small” and affirmed in their conclusion that “there are sufficient studies to allow us to conclude that aerobic, resistance, and combined exercise have …