10,000 steps a day to improve health: investigating fast and slow walking speeds

Abstract

PURPOSE: This study investigated whether individuals walking 10,000 steps per day at fast and slow walking speeds are likely to achieve the minimum recommended daily energy expenditure from physical activity. RELEVANCE: The promotion of participation in physical activity (PA) and exercise is increasingly important in physiotherapy practice. One strategy is to encourage walking; the British Heart Foundation (2005: http://www.bhf.org.uk) suggest a minimum of 10,000 steps per day to reduce risk factors for disease. The American College of Sports Medicine (ACSM) recommend that at least 140 kilocalories per day are expended through PA (Balady et al., 2000: ACSM's Guidelines for Exercise Testing and Prescription). However, there is a lack of research to investigate whether individuals walking 10,000 steps per day expend more than 140 kilocalories, and whether walking speed influences the likelihood of meeting ACSM guidelines. PARTICIPANTS: A convenience sample of 30 undergraduate students was recruited (12 men: mean age 25.5 years; mean height 190.5 cm; mean weight 75.0 kg; 18 women: mean age 22.3 years; mean height 166.5 cm; mean weight 58.3 kg). Individuals with relevant medical history were excluded. Ethical approval was granted by Queen Margaret University College research ethics committee. METHODS: An experimental samesubject design was used in a laboratory-based study comparing physical activity energy expenditure (PAEE: kilocalories) while walking at 3.2 kilometres per hour (kph: slow speed) and 6.4kph (fast speed). Each participant walked for 1,000 steps on a level treadmill, measured using the tally-count method, while wearing a Tritrac-R3D accelerometer to monitor PAEE (kilocalories). Data were collected on two separate days and the order of walking speeds was randomised. ANALYSIS: Data were processed by multiplying PAEE achieved during 1,000 steps on a treadmill by 10 to estimate the likely PAEE from the recommended 10,000 steps. The percentage of individuals who would theoretically achieve the recommended level of PAEE was calculated. The estimated PAEE for each walking speed was compared using the Wilcoxon signedranks test as not all the data were normally distributed (Shapiro- Wilks: 3.2 kph trial: p = 0.03; 6.4 kph trial: p = 0.00). RESULTS: Out of 30 participants, 29 (96.7%) participants achieved the daily PAEE recommended by the ACSM during the slow walking speed (3.2 kph). The theoretical PAEE (kilocalories) from walking 10,000 steps was significantly greater at the faster walking speed (Z=-4.782, p = 0.000). CONCLUSIONS: On extrapolation from 1,000 steps on a treadmill, energy expenditure while walking 10,000 steps at a slow walking speed is likely to meet ACSM recommendations, although significantly more energy is expended at a faster walking speed. This exploratory study used a controlled setting that removed the impacts of conditions such as gradient and wind resistance; it is likely that the estimate of PAEE during 1000 steps on a treadmill underestimates the energy expended in a real life setting. Further field-based work is recommended, including the impact of accumulating short or long periods of stepping. IMPLICATIONS: These results suggest that physiotherapists can recommend the accumulation of 10,000 steps per day while walking at slow or fast speeds.