Walking faster: distilling a complex prescription for type 2 diabetes management through pedometry.
W ith the growth of pedometry, physical activity recommendations have been distilled to a simple focus on ambulatory volume (i.e., 10,000 steps/day). Although energy balance may be most affected by volume, the concomitant lack of focus on physical activity intensity may undermine realization of intensity-dependent outcomes for those with type 2 diabetes, particularly cardiorespiratory fitness because of its inverse association with HbA1c (A1C) (1) and its predictive power for cardiovascular mortality and morbidity in this population (2–4). Historically, a multicomponent framework, commonly known as FITT (frequency, intensity, time, and type) was used to prescribe how often (frequency per week), at what intensity (typically as indicated by heart rate), for how long (duration or time), and what type of activity (typically aerobic) one should pursue for health or performance outcomes. At a population level, there has been a secular trend in the emphasis on the interrelated factors of FITT. For example, in 1975, physical activity recommendations promoted aerobic exercise (type) at 3–5 days/ week (frequency) at 70–90% of heart rate reserve (intensity) for 20–45 min (time). By 2000, recommendations had evolved to promote aerobic activity 7 days/week at an intensity of 40–85% of heart rate reserve for 20 min (5). The variables that compose this framework for prescription are contained within the clinical practice guidelines from both the American Diabetes Association and the Canadian Diabetes Association (5,6). Regardless of the details of the framework underlying these recommendations, however, the challenge remains how to 1) feasibly translate all FITT factors outside of the exercise physiology laboratory and 2) motivate lifelong physical activity in the type 2 diabetic population. Pedometers may help meet both these challenges. We recently reported that individuals with type 2 diabetes naturally walk at a speed (intensity) that is slower than that associated with the minimal intensity (i.e., moderate) required to derive health benefit, despite increasing their number of steps taken per day (8). Hence, we evaluated a simple educational framework designed to help individuals with type 2 diabetes called Pick up the Pace (PUP; i.e., increasing the intensity by increasing the speed of walking), which recommends 30 min/day on at least 3 days/week within the context of a pedometer-based program. We hypothesized that increased walking speed would result in an improved metabolic risk profile among people with established type 2 diabetes, specifically targeting glycemia and cardiorespiratory fitness.