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

ABSTRACT: 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 VO(2) 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.