Methods. Mark A. Tully and Margaret E. Cupples. Study Design

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1 Journal of Physical Activity and Health, 2011, 8, Human Kinetics, Inc. UNISTEP (University Students Exercise and Physical Activity) Study: A Pilot Study of the Effects of Accumulating 10,000 Steps on Health and Fitness Among University Students Mark A. Tully and Margaret E. Cupples Background: Recent public health initiatives have promoted accumulating 10,000 steps per day. Little previous research has evaluated its effects in young adults. The aim of this study was to determine the effects of taking 10,000 steps per day on fitness and cardiovascular risk factors in sedentary university students. Methods: Healthy, sedentary students (mean age ± SD 6.17) were randomly allocated to take 10,000 steps per day or to a control group who maintained their habitual activity. Members of the 10,000 step group wore a pedometer and reported daily step count in a diary. Outcome measurements (20-meter multistage shuttle run, BMI, and blood pressure) were measured before and after 6 weeks. Results: There were no significant differences between the groups at baseline. After 6 weeks, the 10,000 steps group were taking significantly more steps ( ± SD vs ± SD ; P =.03).No changes were observed in fitness, or BMI (P >.05). Significant reductions in blood pressure (P =.04) in the 10,000 step group. Conclusions: A daily target of 10,000 steps may be an appropriate intervention in sedentary university students to increase their physical activity levels. The positive health benefits of simple everyday physical activity should be promoted among health professionals. Keywords: pedometer, walking Physical inactivity is a significant cause of mortality and morbidity worldwide. 1 Every adult is recommended to accumulate at least 30 minutes of moderate intensity exercise, 5 days a week, 1 but few people in Northern Ireland meet this target. 2 Recently, public health initiatives have included recommendations that individuals should aim to walk 10,000 steps per day, using pedometers as a standardized measurement of physical activity. 3 This recommendation has largely been based on epidemiological data and there is limited data from randomized controlled trials (RCTs) of taking 10,000 steps per day. A recent systematic review, 4 identified 9 randomized controlled trials, of which 3 reported an assessment of the effects of walking 10,000 steps per day on physical activity and health. A range of outcomes were reported, from no effect on body mass index (BMI), waist and hip circumference, or blood pressure in people with type 2 diabetes, 5 to a significant reduction in weight and systolic blood pressure in postmenopausal women. 6 However, only 4 studies involved healthy participants and few included students.. None of the studies reported an examination of the effects on change in a validated measure of fitness, which is an independent risk factor for cardiovascular disease 7 The authors are with the Centre of Excellence for Public Health (NI), Queen s University Belfast, Belfast, Northern Ireland, United Kingdom. and has been shown to improve following moderate intensity walking programs. 8 Since two-thirds of university aged adults are inactive 6,9 and pedometer determined steps reduce with age in adolescents, 10 it would appear important to examine the effects of interventions to promote physical activity on health and fitness in this group. Previous research has shown that University students who use public transport instead of driving have higher levels of physical activity, which may help overcome the challenges of balancing study, work, and social commitments. 11 This suggests that changes in physical activity in University students may be possible by adopting new behaviors, but this needs to be tested in a randomized controlled trial. The aim of this pilot study was to determine the feasibility of conducting a pedometer intervention in the university setting and to provide data for a fully powered trial of the effects of accumulating 10,000 steps per day on fitness and risk factors for cardiovascular disease in healthy, sedentary, university students. Study Design Methods 141 medical, dental, and biomedical science students of Queen s University Belfast were approached and asked to complete the long form of the International Physical 663

2 664 Tully and Cupples Activity Questionnaire (IPAQ) 12 and indicate their willingness to participate in a walking program. Queen s University is located in inner city Belfast and students and the campus is split over 2 sites, 1 mile apart. Seventy-one were classified as inactive or moderately active, of whom 31 were willing to participate and invited to a familiarization session (Figure 1). Twelve individuals attended this session at which the study was explained, and written informed consent sought. Individuals were excluded if they had any known disease that would prevent them taking regular exercise. Those who consented to participate wore a pedometer (Oregon Scientific WA101, USA) for 7 days before entering the trial to ascertain preintervention activity levels. After the 7 days preintervention outcome measurements were made and individuals were allocated to a 10,000 step exercise intervention or a control group using computer generated random numbers by a researcher not involved in the day-to-day running of the trial. Measurements were made at baseline (preintervention) and after 6 weeks (postintervention) in the university Physical Education Centre by the same researcher, who was blinded to the group allocation. Outcome Measurements Height (Seca Leicester stadiometer, Germany) and body mass (Seca 761 scales, Germany) were measured. Waist and hip circumferences were measured using standard procedures. Aerobic fitness was estimated using the 20-m multistage shuttle run and calculated predicated VO 2 max using the equation of Flouris et al. 13 Blood pressure (BP) and heart rate were taken after a 5-minute resting period in the seated position, as the average of 2 measurements, with a 1 minute interval between, using a Digital Sphygmomanometer (Omron M5-I, Japan). Statistical Analyses As there are no previous pedometer interventions in this population, a sample size calculation was estimated on the findings on a previous study of a stair climbing intervention in university aged adults. 14 It was estimated that a 15% change in predicted VO 2 max within the intervention group could be detected with 80% power with 8 subjects in the 10,000 step group. Data were analyzed using the computer program SPSS v14.0. Between group Figure 1 Flow of participants through the trial.

3 UNISTEP Study 665 differences were compared using independent t tests and within group changes using paired t tests. The extent of change (difference of pre- and postintervention measurements) between the groups was compared using independent t tests. The Research Ethics Committee, Queen s University, Belfast approved the study (September 2006). Interventions Participants in the 10,000 step group were asked to accumulate 10,000 steps per day and to wear a pedometer (Oregon Scientific WA101, USA) every day for 6 weeks, chosen to ensure the intervention could be completed in a single semester, thus avoiding any potential seasonal differences in how participants respond. Control group participants were asked to wear their pedometer every day for 6 weeks and record the number of steps they took per day without modifying any aspect of their lifestyle. All participants were asked to complete weekly diaries recording the number of steps they took per day. Every 2 weeks diaries were returned to the researcher, who posted new ones and phoned or ed participants to resolve any difficulties. Results Twelve inactive or moderately active first and second year students (10 females and 2 males) agreed to participate and were randomly allocated to one of the groups. All participants completed the trial. The mean age of participants was (SD ± 6.17) years. There were no significant differences in daily step counts between the groups at baseline (Table 1). All participants in the 10,000 step group met their daily goal and significantly increased their daily step count over the course of the study (Table 2). There were no significant differences between the groups for any of the other outcome measurements at baseline (Table 2). Adherence with the program, measured as the number of days of data that was returned on the diaries as a percentage of the total number of days in the program, was 84.9%. Following the 6-week walking program, there was a significant reduction in BP in the 10,000 step group which was not observed in the control group (Table 2). There were no changes in fitness or anthropometric outcomes. Discussion This study demonstrates that it is feasible to conduct a pedometer intervention in the university setting and that translating the emerging recommendation of walking 10,000 steps per day into a 6-week, unsupervised walking program leads to a significant increase in physical activity in sedentary university students. The results can be used to inform a sample size calculation for a fully powered trial. Our finding of a significant increase in number of steps per day among the intervention group who were given a step goal of 10,000 steps per day, is in keeping with a recent systematic review published after our study began. 4 This suggests that individuals seeking to increase their physical activity may be assisted through advice to aim for 10,000 steps per day. Of interest was the finding of no change in fitness in the 10,000 step group. Fitness is an independent risk factor for heart disease 7 and has been shown to improve following interventions promoting self-paced moderate intensity walking. 8 Our intervention offered no advice regarding speed of walking. Health professionals providing physical activity advice may therefore need to stipulate the speed of walking to gain additional health benefits. However, the lack of change in fitness may be related to the relatively short duration of the intervention and should be confirmed in longer studies. The intervention also led to a significant reduction in blood pressure among this group of younger adults. Blood pressure was included as an outcome measure to test the effects of walking on cardiovascular health in university aged adults. Although none of the subjects in this study were hypertensive (BP >140/90 mmhg), the American College of Sports Medicine 15 states that the positive relationship between cardiovascular risk and blood pressure occurs with blood pressure as low as Table 1 Baseline Comparison of Outcome Measurements in 10,000 Step and Control Groups 10,000 step group (n = 8) Control group (n = 4) Comparison at baseline P Number of steps per day (5379.3) (2837.5) 0.14 Weight (kg) (17.35) (13.77) 0.79 BMI (kg/m 2 ) (6.55) (3.13) 0.99 WHR (cm) 0.83 (0.04) 0.83 (0.04) 0.55 Predicted VO 2 max (ml/kg/min) (4.62) (4.59) 0.52 Systolic BP (mmhg) (15.62) (11.85) 0.28 Diastolic BP (mmhg) (8.23) (8.50) 0.22

4 Table 2 Change in Outcome Measurements Over Course of Study in 10,000 Step and Control Groups Preintervention 10,000 step group (n = 8) Control group (n = 4) Postintervention Change within group P Preintervention Postintervention Change within group P Between group difference P Number of steps per day (5379.3) (6851.3) 0.00* (2837.5) (3931.5) ** Weight (kg) (17.35) (17.11) (13.77) (11.76) BMI (kg/m 2 ) (6.55) (6.50) (3.13) (2.30) WHR (cm) 0.83 (0.04) 0.82 (0.11) (0.04) 0.83 (0.04) Predicted VO2max (ml/kgmin) (4.62) (6.34) (4.59) (4.41) Systolic BP (mmhg) (15.62) (9.80) 0.04* (11.85) (9.73) ** Diastolic BP (mmhg) (8.23) (8.34) 0.04* (8.50) (7.65) * P <.05 within groups, post intervention versus baseline. ** P <.05 comparison of extent of change between groups. 666

5 UNISTEP Study /75 mmhg. Although the changes observed in this study were not clinically significant, they are in keeping with that found in a systematic review of the effects of walking on blood pressure in mainly middle aged and older adults by Kellley et al. 16 Given the importance of lifestyle in modifying cardiovascular risk, 17 and that health professional who are themselves physically active are more likely to promote physical activity among their patients, 18 it is necessary to identify methods of increasing physical activity in health professionals. The findings of this study suggest that a pedometer intervention may be a suitable intervention early in their careers. Study Limitations and Strengths Previous research has demonstrated that 70% of students do not meet the previously recommended level of exercise. 9 The current study indicates that pedometer interventions may be an acceptable approach to address this problem. However, Bravata et al 4 recognized that there is a need to determine if the effects of pedometer based interventions, like those demonstrated in the current study, can be maintained long term. The data presented here demonstrate that pedometers are a feasible method of promoting increases in physical activity in the university setting. The study needs to be replicated in a larger sample to confirm the findings in a fully powered trial. Conclusions A daily target of 10,000 steps may be an appropriate intervention in sedentary university students to increase their physical activity levels. However, the sustainability of such a behavior change still needs to be assessed. Acknowledgments Thanks to Tara Smith who assisted in this study as part of her BSc undergraduate research project, Queen s University Belfast. MT & MEC contributed to the design of the study, interpretation of the results and preparation and approval of the final manuscript. MT was also involved in the outcome measurements. MAT and MEC are co-funded by the Centre of Excellence for Public Health (Northern Ireland), a UKCRC Public Health Research Centre of Excellence. Funding from the British Heart Foundation, Cancer Research UK, Economic and Social Research Council, Medical Research Council, Research and Development Office for the Northern Ireland Health and Social Services and the Wellcome Trust, under the auspices of the UK Clinical Research Collaboration, is gratefully acknowledged. References 1. Haskell WL, Lee IM, Pate RR, et al. Physical activity and public health: updated recommendation for adults from the American College of Sports Medicine and the American Heart Association. Med Sci Sports Exerc. 2007;39(8): NISRA. Northern Ireland Health and Social Wellbeing Survey 2001: physical activity bulletin (bulletin number 3). Belfast: Northern Ireland Statistics and Research Agency; Tudor-Locke C, Hatano Y, Pangrazi RP, Kang M. Revisiting how many steps are enough?. Med Sci Sports Exerc. 2008;40(7, Suppl):S537 S Bravata DM, Smith-Spangler C, Sundaram V, et al. Using pedometers to increase physical activity and improve health: a systematic review. JAMA. 2007;298: Araiza P, Hewes H, Gashetewa C, Vella CA, Burge MR. Efficacy of a pedometer-based physical activity program on parameters of diabetes control in type 2 diabetes mellitus. Metabolism. 2006;55(10): Keller S, Maddock JE, Hannöver W, Thyrian JR, Basler HD. Multiple health risk behaviors in German first year university students. Prev Med. 2008;46(3): Ekelund LG, Haskell WL, Johnson JL, Whaley FS, Criqui MH, Sheps DS. Physical fitness as a predictor of cardiovascular mortality in asymptomatic North American men: the Lipid Research Clinics Mortality Follow-up Study. N Engl J Med. 1988;319: Tully MA, Cupples ME, Hart ND, et al. Randomised controlled trial of home-based walking programmes at and below current recommended levels of exercise in sedentary adults. J Epidemiol Community Health. 2007;61(9): Haase A, Steptoe A, Sallis JF, Wardle J. Leisure-time physical activity in university students from 23 countries: associations with health beliefs, risk awareness, and national economic development. Prev Med. 2004;39(1): Hohepa M, Schofield G, Kolt GS, Scragg R, Garrett N. Pedometer-determined physical activity levels of adolescents: differences by age, sex, time of week, and transportation mode to school. J Phys Act Health. 2008;5(Suppl 1):S140 S Villanueva K, Giles-Corti B, McCormack G. Achieving 10,000 steps: a comparison of public transport users and drivers in a university setting. Prev Med. 2008;47(3): Craig CL, Marshall AL, Sjöström M, et al. International physical activity questionnaire: 12-country reliability and validity. Med Sci Sports Exerc. 2003;35(8): Flouris AD, Metsios GS, Koutedakis Y. Enhancing the efficacy of the 20 m multistage shuttle run test. Br J Sports Med. 2005;39: Boreham CAG, Kennedy RA, Murphy MH, Tully M, Wallace WFM, Young I. Training effects of short bouts of stair climbing on cardiorespiratory fitness, blood lipids, and homocysteine in sedentary young women. Br J Sports Med. 2005;39: Pescatello LS, Franklin BA, Fagard R, Farquhar WB, Kelley GA, Ray CA; American College of Sports Medicine. American College of Sports Medicine position stand. Exercise and hypertension. Med Sci Sports Exerc. 2004;36(3): Kelley GA, Kelley KA, Tran ZV. Aerobic exercise and resting blood pressure: a meta-analytic review of randomized, controlled trials. Prev Cardiol. 2001;4(2): Kabir Z, Bennett K, Critchley JA, Capewell S. Can small changes in cardiovascular risk factors predict large future reductions in coronary heart disease mortality in Ireland? Eur J Epidemiol. 2007;22(2): McKenna J, Naylor PJ, McDowell N. 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An Examination of the Effects of a Curriculum Based Pedometer Program in Two Age Groups: Adults and Pre-Adolescent Children

1 of 5 5/5/2010 1:38 PM Home Current Issue Editorial Board Instructions for Authors Contact Lethbridge Undergraduate Research Journal ISSN 1718-8482 An Examination of the Effects of a Curriculum Based