Step rate-determined walking intensity and walking recommendation in Chinese young adults: a cross-sectional study

There is lack of data on the physiological characteristics of over ground walking and walking recommendations for Chinese young adult. The purpose of the study was to measure walking-related energy expenditure during field testing, to identify step-rate cut-point associated with moderate and vigorous intensity, and to translate physical activity (PA) guidelines into walking goals for Chinese young adults. Design: Cross-sectional analytic study. Setting: Two communities from Beijing and Shanghai in China. Participants: A sample of 226 Chinese adults (117 men, 109 women) with a mean age of 21.7 (+/- 0.2) years, volunteered to participate in the study. All Participants were recreationally active without orthopaedic limitations, free of chronic diseases, not taking any medications that affect metabolism and non-smokers. Outcome measures: All the participants completed four 6 minincremental over ground walking at different speeds of 3.8, 4.8, 5.6 and 6.4 km/h, respectively. Indirect calorimeter was used to measure energy expenditure at each speed. Receiver operating characteristic curves were used to determine the step-rate cut-points associated with moderate and vigorous intensity activity. Results: At the same walking speed, step counts per minute were higher in women than in men. No significant differences were found in VO2 per weight (ml/kg/min) between women and men. Step-rate cut-point associated with walking at 3 metabolic equivalents (METs) and 6METs were 105 and 130 step/min when analysing men and women together. There were slight differences on the cut-points between women and men if data were analysed separately. Conclusions: In order to meet PA guidelines, Chinese young adult should walk 30 min with at least 105 step/min or 3150 steps or 2 km with the same step-rate per day. Walking at a higher speed of 130 step/min might provide additional health benefit.