This meta‐analysis quantified the effect of FITT (Frequency, Intensity, Time and Type) manipulation on exercise adherence. Databases were searched from inception to 09‐2018. Manipulation of Intensity resulted in a moderate, significant decrease in adherence (MD: ‐3.3, 95% CI: ‐6.1 to ‐0.5), and for the remaining FITT components there were trivial‐small, non‐significant effects. When stratified by chronic disease status, for populations with chronic diseases increasing Intensity resulted in a moderate but non‐significant decrease in adherence (MD: ‐3.6, 95% CI: ‐7.4, 0.3) and increasing Time resulted in a small, significant decrease in exercise adherence (MD: ‐4.9, 95% CI: ‐9.4 to ‐0.4). Additionally, omission of a behavioral model resulted in a moderate but non‐significant decrease in exercise adherence (MD: ‐4.0, CI: ‐8.3 to 0.2). For healthy populations, FITT manipulation and omission of behavioral model resulted in trivial‐small, non‐significant effects. In conclusion, manipulation of FITT and use of behavioral models may be of greater importance to exercise adherence in diseased population. In particular, increasing Intensity and Time and omitting a behavioral model may decrease adherence. The current meta‐analysis elucidates gaps in the literature and can assist clinicians and clinical exercise physiologists in determining the importance of FITT manipulation to exercise adherence.

Summary: Background and objectives: Visceral fat is associated with increased cardiovascular risk in adults, but studies in youth are limited. We assessed associations between visceral fat and arterial stiffness in youth with healthy weight, obesity and type 2 diabetes and determined whether relationships were independent of clinical estimates of body fatness.Methods: This cross‐sectional sample included youth ages 10–23 years (67% female, 56% non‐black) with healthy weight (body mass index [BMI] = 5th–85th percentile, n = 236), obesity (BMI ≥ 95th percentile, n = 224) and type 2 diabetes (BMI ≥ 95th percentile, n = 145). Visceral fat was assessed via dual‐energy X‐ray absorptiometry. Carotid‐femoral pulse wave velocity (PWV) was assessed via applanation tonometry. Obesity and type 2 diabetes groups were combined for final analyses. Analyses accounted for age, sex, ancestry and mean arterial pressure.Results: Visceral fat and PWV were greater in youth with obesity versus healthy weight (p < 0.001). In youth with obesity, but not healthy weight, visceral fat was positively associated with PWV (p < 0.001) and was predictive of PWV beyond BMI and waist circumference.Conclusions: Visceral fat likely contributes to subclinical cardiovascular complications in youth. Since cardiovascular health tracks from adolescence to adulthood, longitudinal studies in youth with obesity are required to define the role of visceral fat in lifelong cardiovascular disease risk.

A ubiquitous aspect of contemporary societies is sedentary behavior (SB), defined as low intensity activities in a seated, reclined, or supine posture. Leading public health agencies, including the World Health Organization, have recognized the strong association between SB and poor health outcomes, particularly cardiovascular disease. However, while public health agencies have begun to advocate for “reductions” in SB, the current US guidelines are typically vague and non-specific. There is good reasoning behind this non-committal advocacy—there is limited mechanistic and clinical evidence to support policy development. To guide SB policy development, it is important to first consider the origins and evolution of SB, including the following: 1) is SB really a novel/contemporary behavior? i.e., how has this behavior evolved? 2) how did our ancestors sit and in what contexts? 3) how does SB interact with 24-hour activity behaviors, including physical activity and sleep? 4) what other historical and contemporary facets of life interact with SB? and 5) in what context do these behaviors occur and how might they provide different evolutionarily novel stressors? This perspective article will synthesize the available evidence that addresses these questions and stimulate discussion pertaining to the lessons that we can learn from an historical and evolutionary perspective. Last, it will outline the gaps in current SB interruption literature that are hindering development of feasible SB reduction policy.