Il cambiamento che possiamo ottenere produce effetti clinicamente rilevanti?

Does the behavioral change we can achieve produce clinically meaningful effects?

Adopting and maintaining a physically active lifestyle provides significant health benefits to people with diabetes and prediabetes by increasing energy expenditure, insulin sensitivity, and physical fitness and decreasing chronic low-grade inflammation. Physical activity (PA)/exercise favors control of hyperglycemia and other risk factors for cardiovascular disease (CVD) and, therefore, it is recommended for diabetes prevention and treatment and for improving overall health. According to current guidelines, people with type 2 diabetes are re-commended to perform at least 150 min/week of moderate-to-vigorous intensity aerobic exercise plus 2-3 sessions/week of resistance exercise on non-consecutive days. Unfortunately, these individuals are usually well below the recommended level of PA and, hence, it is difficult for them to put into action guideline recommendations for a number of external and internal barriers, thus suggesting the need for effective strategies to promote a sustained behavior change. Several randomized clinical trials have shown that supervised exercise programs are effective in improving surrogate endpoints such as blood glucose and other CVD risk factors, physical fitness, and well-being. However, such programs are not suitable for long-term implementation in routine clinical practice and adherence to PA/exercise is usually strictly dependent on participation to supervised sessions and falls once the intervention ends. In this regard, counseling interventions appear to be more feasible and adequate to promote a true, long-lasting behavior change. A limited number of studies have tested the efficacy of counseling interventions designed to promote walking through the provision of pedometers. These interventions resulted in modest and transient increases in moderate-to-vigorous PA (MVPA) and, accordingly, failed to significantly improve CVD risk factors and other surrogate outcomes or to produce sustained increases in cardiorespiratory fitness. These results are in contrast with those of several epidemiological surveys, showing that, in physically inactive and sedentary or unfit individuals, even modest amounts of (MV)PA, corresponding to one-third to one-half of those recommended by guidelines, exert a beneficial impact on morbidity and mortality. This discrepancy might be explained by the fact that walking-based interventions are focused only on leisure-time MPVA. Conversely, current guidelines consider also other domains, such as sedentary behavior and light-intensity PA (LPA), and other settings, such as home, work and commuting, as they recommend also to decrease the amount of sedentary (SED)-time and to interrupt prolonged sitting with bouts of LPA every 30 min. In fact, in the Italian Diabetes and Exercise Study 2 (IDES_2), a counseling intervention targeting both MVPA and sedentary behavior was effective in promoting increases in MVPA, which were modest but sustained over a three-year follow-up and associated with larger decreases in SED-time and corresponding increases in LPA. This resulted in clinically meaningful improvements in physical fitness and, to a lesser extent, in CVD risk factors and scores over a three-year follow-up. Conversely, no clinically meaningful effects were observed in counseling intervention targeting only SED-time. In conclusion, counseling interventions are effective in producing clinically meaningful effects, even when resulting in only modest increments in leisure-time MVPA, provided that they also target the other domains and settings of PA/sedentary behavior.