OBJECTIVETo evaluate the feasibility of free-living walking training in type 2 diabetes patients, and to investigate the effects of interval-walking training versus continuous-walking training upon physical fitness, body composition, and glycemic control.RESEARCH DESIGN AND METHODSSubjects with type 2 diabetes were randomized to a control (n = 8), continuous-walking (n = 12), or interval-walking group (n = 12). Training groups were prescribed five sessions per week (60 min/session) and were controlled with an accelerometer and a heart-rate monitor. Continuous walkers performed all training at moderate intensity, whereas interval walkers alternated 3-min repetitions at low and high intensity. Before and after the 4-month intervention, the following variables were measured: VO(2)max, body composition, and glycemic control (fasting glucose, HbA(1c), oral glucose tolerance test, and continuous glucose monitoring [CGM]).RESULTSTraining adherence was high (89 ± 4%), and training energy expenditure and mean intensity were comparable. VO(2)max increased 16.1 ± 3.7% in the interval-walking group (P <0.05), whereas no changes were observed in the continuous-walking or control group. Body mass and adiposity (fat mass and visceral fat) decreased in the interval-walking group only (P <0.05). Glycemic control (elevated mean CGM glucose levels and increased fasting insulin) worsened in the control group (P <0.05), whereas mean (P = 0.05) and maximum (P <0.05) CGM glucose levels decreased in the interval-walking group. The continuous walkers showed no changes in glycemic control.CONCLUSIONSFree-living walking training is feasible in type 2 diabetes patients. Continuous walking offsets the deterioration in glycemia seen in the control group, and interval walking is superior to energy expenditure-matched continuous walking for improving physical fitness, body composition, and glycemic control.
Diabetes Care, 2013, Vol 36, Issue 2, p. 228-236
Journal Article; Randomized Controlled Trial; Research Support, Non-U.S. Gov't; Blood Glucose; Blood Pressure; Body Composition; Diabetes Mellitus, Type 2; Energy Intake; Energy Metabolism; Exercise; Exercise Therapy; Female; Humans; Male; Middle Aged; Physical Fitness; Walking