Walking Faster
Distilling a complex prescription for type 2 diabetes management through pedometry
- Steven T. Johnson, MSC1,
- Linda J. McCargar, PHD, RD1,
- Gordon J. Bell, PHD2,
- Catrine Tudor-Locke, PHD, FACSM3,
- Vicki J. Harber, PHD2 and
- Rhonda C. Bell, PHD1
- 1Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
- 2Faculty of Physical Activity and Recreation, University of Alberta, Edmonton, Alberta, Canada
- 3Department of Exercise and Wellness, Arizona State University East, Mesa, Arizona
- Address correspondence and reprint requests to Rhonda C. Bell, PhD, Department of Agricultural, Food and Nutritional Science, 4-10 Agriculture Forestry Centre, Edmonton, Alberta, Canada T6G 2P5. E-mail: rhonda.bell{at}ualberta.ca
With 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 …
