Walking At Work: A Pedometer Study Assessing The Activity Levels Of Doctors
J Atkinson, R B Goody, C A Walker
Correspondence to: Dr Craig A Walker, SHO in Emergency Medicine, North Woodend. Durno, Pitcaple, Inverurie, Aberdeenshire, AB51 5EP
Email: dr.walker@fsmail.net
SMJ 2005 50(2): 73-74
Abstract
Background: The World Health Organisation cites a sedentary lifestyle as one of the top ten causes of morbidity and mortality worldwide.4 A recent, large-scale clinical study showed that brisk walking and vigorous exercise are associated with substantial (and similar) reductions in the incidence of coronary heart disease.6 Current guidelines suggest 10,000 steps per day as an appropriate activity target for healthy adults.7 Aims: This study aims to assess whether doctors are meeting this daily walking target during working-hours, and whether additional out-of-hours exercise is required. Methods: 16 doctors from St. John’s Hospital in Livingston (comprising 4 Medical Consultants, 4 Surgical Consultants, 4 Medical PRHOs and 4 Surgical PRHOs) each used a belt-worn pedometer to record all steps made during 5 consecutive day shifts. Stride length and total daily steps were recorded. Steps made out-with working hours were not counted. Total steps and hours worked were recorded at the end of each day. Results: Average daily steps recorded were 7907 (Medical PRHOs), 5068 (Surgical PRHOs), 4822 (Surgical Consultants) and 4647 (Medical Consultants). P values of <0.1 were obtained for the variation in steps between the Medical PRHOs and both the Consultant Surgeons and Consultant Physicians. Distance walked per shift varied from 3.84 (Consultant Physicians) to 6.85 kilometres (Medical PRHOs). Conclusion: Walking at work does provide a substantial proportion of a doctor’s recommended daily activity quota. However, it is still necessary to engage in additional, out-of-hours exercise in order to consistently meet the current recommendations for physical exercise.
Key words: Pedometer; doctors; exercise; walking; work
Introduction
The benefits of physical activity have been well documented. Evidence shows that exercise is related to a reduced risk of cardiovascular and cerebrovascular disease, hypertension, non insulin dependent diabetes mellitus, colorectal cancer, osteoporosis and depression.1,2,3 The importance of exercise is such that the WHO cites a sedentary lifestyle as one of the top ten causes of morbidity and mortality worldwide.4
Currently, the Health Education Authority and Health Education Board for Scotland recommend we engage in 30 minutes of moderate intensity physical exercise five days per week.5 One study, involving 72,000 nurses, comparing brisk walking and vigorous exercise concluded that both were associated with substantial reductions in the incidence of coronary heart disease. Significantly, these reductions were of similar magnitude.6
Walking is a sustainable form of physical exercise which is flexible, “popular, inexpensive, and carries a low risk of injury ”.1 Alternative guidelines suggest 10,000 steps per day to be an appropriate activity target for healthy adults.7 This is easily measured using belt-worn pedometers which are inexpensive and readily available.
Measuring only leisure-time activity may underestimate exercise levels; a broader concept to include work-based exertion provides a better approximation of total physical activity.8 The aim of this study is to calculate the number of steps taken at work by doctors in order to determine whether supplementary exercise is required to meet the current 10,000 step guideline.
Method
Doctors from St. John’s Hospital, Livingston, West Lothian were voluntarily enlisted into this study. The doctors studied were those who were scheduled to be working normal day shifts during the study period. They agreed to wear a pedometer for five consecutive day shifts and record the total number of steps walked each day. “High Gear Scanner Pedometers” were used in all cases. Only walking while at work was included; the journey to and from home was not recorded.
Stride length was calculated for each participant by recording the number of steps taken to complete a standard 20m test distance. Pedometers were assessed for accuracy using manual step counting along a length of corridor. In order to check whether the pedometers registered movements made whilst sitting, one volunteer wore the pedometer for a one-hour period whilst performing routine ward duties (writing in notes, requesting blood samples, etc.).
Four volunteers from each of the following groups were studied:
· General medical consultants
· General surgical consultants
· Medical pre-registration house officers
· Surgical pre-registration house officers
Stride length and steps taken were used to calculate distances walked by each participant. Shift times were recorded.
Results
All pedometers were 100% accurate when tested walking along straight corridor lengths at normal pace. Similarly, no activity was recorded whilst the volunteer performed routine ward duties whilst seated for one hour. Four volunteers from each staff category were enlisted. The mean number of days wearing the pedometer was 4.89 days (SD 0.32) and hours per day of 9.53 (SD 1.46). There was wide variation between results within the individual groups (Table I). On average, medical house officers were found to walk the most number of steps per day (7907) and consultant physicians walked the least (4647). Surgical house officers and consultant surgeons walked 5068 and 4822 steps, respectively. On t-test analysis of group mean steps per shift there was a significant difference between the medical PRHOs and both the consultant surgeons and consultant physicians (p<0.1). The individual total steps per day and group average are summarised in Figure I.
Accounting for individuals’ stride length, the average distance walked each shift by category was also calculated. Shift times varied depending on specialty (Figure II). For interest’s sake, we used the values obtained for average number of steps per hour and individual stride lengths to estimate the distance walked by each group in an average month (taking an average working week as 48 hours).
Medical PRHOs would have walked by far the most, at 155 kilometres; the approximate distance between Aberdeen and Inverness (or Edinburgh and Newcastle). The surgical PRHOs and medical consultants would be projected to walk 86 and 82 kilometres, respectively. Surgical consultants would have walked the shortest distance, at approximately 80 kilometres (5km more than the distance between Edinburgh and Glasgow). The difference between the projected distances walked for the medical and surgical consultants was produced by variation in stride lengths (medical consultants averaged 82.6cm, whereas surgical consultants averaged 81.9cm), with the surgeons who had the longer stride lengths walking proportionally more steps.
Discussion
The medical house officers of St John’s Hospital walked significantly further than any of the other groups surveyed. In a standard eight hour shift they obtained nearly 80% of the 10,000 steps per day target (Figure III).
Interestingly, the medical department is spread over eight wards on four floors. Due to the team (rather than ward) based practice any one medical house officer may have patients on all of these wards. In contrast, the surgical department runs ward based practice and there are only three wards in total, all of which are adjacent. Additionally, the compositions of physicians’ days are markedly different to surgeons who, by definition, are required to spend large proportions of their time in theatre and, generally, have shorter ward rounds. It is interesting to note that, during the study period, the consultant surgeons recorded the highest number of hours but were only marginally above the consultant physicians in average number of steps (4822 versus 4647).
Other reasons for the discrepancies between individuals and categories could be due to differences in motivation or efficiency of job organisation. To standardise for this we would liked to have followed the same house officer while they completed both their medical and surgical placements within the hospital. Further research could review the same house officers repeatedly over their first six months to see if increased efficiency and job familiarity affected the distances walked.
The doctors studied were those who were scheduled to be working normal day shifts during the study period. Although all of the doctors who were asked to participate in the study were free to decline the offer, none did so. It is still possible that the doctors who took part could have been, by chance, fitter or more active than their peers, shown by their willingness to participate in the study.
Although pedometers were checked for accuracy whilst walking and performing duties in a seated position, this study may have been limited by the accuracy of the pedometers when on stairs and running. In addition, some “steps” may have been recorded by vigorous/quick movements made by the consultant surgeons whilst operating (if sufficient movement was produced at waist level). Other studies have found that the very fact that steps are being counted encourages the participant to walk further.9 Only weekday shifts were studied formally but anecdotally on the evening, night and weekend shifts much greater distances were covered due to the ‘on-call’ pattern of work. Due to instigation of full shift patterns these shifts may form a large proportion of a house officer’s overall shifts and therefore their total work-related exercise. Omitting these shifts may have underestimated the total exercise at work of current junior doctors.
Conclusion
Walking at work does provide a substantial proportion of a doctor’s recommended daily activity quota. However, it is still necessary to engage in additional, out-of-hours exercise in order to consistently meet the current recommendations for physical exercise.
REFERENCES
1 Hardman AE. Physical activity in health: current issues and research needs. Int J of Epid 2001: 30: 1193-7.
2 Wannamethee SG, Shaper AG, Walker M. Changes in physical activity, mortality, and incidence of coronary heart disease in older men. Lancet: 1998: 351(9116): 1603
3 Blair SN et al. Physical fitness and all-cause mortality. A prospective study of healthy men and women. JAMA 1989: 262(17): 2395-2401.
4 Using the countryside as a health resource to promote physical activity: A summary of the UK Walking the way to Health and Green Gym initiatives. Paper given by Veronica Reynolds, WHI Regional Case Officer, at the International Trails Conference, Australia, October 2002.
5 British Heart Foundation Physical Activity Toolkit – accessed 26/08/04 via HYPERLINK “http://www.bhf.org.uk/publications/index_home.asp?SecID=18” http://www.bhf.org.uk/publications/index_home.asp?SecID=18
6 Manson JE, et al. A prospective study of walking as compared with vigorous exercise in the prevention of coronary heart disease in women. NEJM 1999;341(9):650-658.
7 Hatano Y. Use of the pedometer for promoting daily walking exercise. International Council for Health, Physical Education and Recreation 1993; 29: 4-8 - quoted in NSMI Walking Initiative information HYPERLINK “http:// www.nsmi.org.uk/nsmi-walking-initiative.html” http://www.nsmi.org.uk/nsmiwalking- initiative.html
accessed 01/05/04
8 Macera C, et al. Physical activity surveillance in the 21st century. Annals of Epidemiology 2000; 10(7):456.
9 Rooney B et al. Is knowing enough? Increasing physical activity by wearing a pedometer. WMJ 2003:102(4):31-6.