Submitting Institution
University of CambridgeUnit of Assessment
Public Health, Health Services and Primary CareSummary Impact Type
HealthResearch Subject Area(s)
Medical and Health Sciences: Public Health and Health Services
Summary of the impact
Physical inactivity is strongly related to coronary heart disease, type 2
diabetes, osteoporosis and some cancers. Research at the University of
Cambridge has focused on the development and validation of methods for
assessing physical activity in population studies and on the application
of these methods to quantify the type and dose of physical activity that
is important for different health outcomes. This research has contributed
to development of public health guidelines. Research into the determinants
of activity levels in different population groups and the evaluation of
interventions aimed at individuals and the wider population has
contributed to NICE guidance on different forms of interventions to
increase physical activity.
Underpinning research
The MRC Epidemiology Unit has a long standing programme in the
development and validation of methods for assessing physical activity in
population studies led by Professor Wareham (since 1993) and, Drs Ekelund
and Brage (since 2003). These methods include subjective and objective
approaches which can be used in different settings, different population
groups and for different purposes. These purposes include the descriptive
epidemiology of physical activity (1), aetiological investigation of the
association between activity and health outcomes, assessment of activity
as part of risk stratification (2) and measurement of activity change in
intervention studies. Between 1993 and 2010, the Unit has developed and
validated a suite of instruments that are fit for purpose, has published
validation studies (e.g. 1,2) and made the methods widely available by
leading the development in 2011 of an on-line Diet and Physical Activity
(DAPA) toolkit which enables researchers to identify the most suitable
instrument for their particular study and to access all the necessary
elements of the measurement instrument to allow them to use it
independently. The Unit has contributed to understanding temporal trends
in physical activity in the United Kingdom (3) and geographical variations
in prevalence of inactivity globally. It has assessed the association in
large-scale cohort studies between overall physical activity, different
domains and different intensities on chronic disease outcomes including
all-cause mortality, cardiovascular disease incidence (4), type 2 diabetes
and cancers. Research using objective measurement of physical activity in
cohort studies of adults and children has contributed to understanding of
the direction and quantification of the relationship between different
intensities of physical activity, sedentary behaviour and obesity and
metabolic disease (5,6).
These results have contributed to recommendations for physical activity
in the UK including recent refinements to focus not only on achieving 5 x
30 minute bouts of moderate to vigorous activity per week, but also to aim
to increase overall activity through whatever means and to diminish
sedentary behaviour. The studies have also informed the target of trials
to evaluate individualistic approaches to promoting physical activity. The
limited effectiveness of such individual approaches has led to investment
in research on understanding the wider population determinants of physical
activity, the effectiveness of planned and natural experimental
interventions that impact on physical activity levels (7) and the
estimation of the long term health benefits of changing activity (8). This
research has been led by the Cambridge UKCRC-funded Centre of Public
Health Research Excellence on Diet and Activity (CEDAR).
References to the research
1. Ekelund, U., H. Sepp, S. Brage, W. Becker, R. Jakes, M. Hennings and
N. J. Wareham (2006). "Criterion-related validity of the last 7-day, short
form of the International Physical Activity Questionnaire in Swedish
adults." Public Health Nutr 9(2): 258-65. PMID:
16571181
2. Wareham, N. J., R. W. Jakes, K. L. Rennie, J. Schuit, J. Mitchell, S.
Hennings and N. E. Day (2003). "Validity and repeatability of a simple
index derived from the short physical activity questionnaire used in the
European Prospective Investigation into Cancer and Nutrition (EPIC)
study." Public Health Nutr 6(4): 407-13. PMID:
12795830
3. Stamatakis, E., U. Ekelund and N. J. Wareham (2007). "Temporal trends
in physical activity in England: the Health Survey for England 1991 to
2004." Prev Med 45(6): 416-23. PMID: 17316777
4. Khaw, K. T., R. Jakes, S. Bingham, A. Welch, R. Luben, N. Day and N.
Wareham (2006). "Work and leisure time physical activity assessed using a
simple, pragmatic, validated questionnaire and incident cardiovascular
disease and all-cause mortality in men and women: The European Prospective
Investigation into Cancer in Norfolk prospective population study." Int
J Epidemiol 35(4): 1034-43. PMID: 16709620
5. Ekelund, U., S. Brage, H. Besson, S. Sharp and N. J. Wareham (2008).
"Time spent being sedentary and weight gain in healthy adults: reverse or
bidirectional causality?" Am J Clin Nutr 88(3): 612-7. PMID:
18779275
6. Steele RM, van Sluijs EM, Cassidy A, Griffin SJ, Ekelund U
(2009).Targeting sedentary time or moderate- and vigorous-intensity
activity: independent relations with adiposity in a population-based
sample of 10-y-old British children. Am J Clin Nutr. 90 (5):
1185-92. PMID: 19776141
7. Yang L, Sahlqvist S, McMinn A, Griffin SJ, Ogilvie D (2010). BMJ. 341:c5293
PMID 20959282
8. Jarrett J, Woodcock J, Griffiths UK, Chalabi Z, Edwards P, Roberts I,
Haines A (2012). Effect of increasing active travel in urban England and
Wales on costs to the National Health Service. Lancet. 379(9832):2198-205.
PMID 22682466
Details of the impact
The establishment of a suite of instruments by the MRC Epidemiology Unit
between 1993 and 2010 for measuring physical activity in different
population groups and settings and the production of an on-line DAPA
toolkit led by the Unit for the MRC Population Health Sciences Research
Network in 2011 to facilitate methodological knowledge exchange (1) has
promoted the use of measurement tools that are fit-for-purpose. For
example, in its report on Measuring diet and physical activity in weight
management programme, the National Obesity Observatory cites the DAPA
toolkit as a source of information on questionnaires (2). It also cites
validation work on the International Physical Activity Questionnaire
(IPAQ) (Ekelund et al, Public Health Nutrition 2006), a widely used
instrument for assessing the prevalence of inactivity which was used
recently in an analysis of global physical activity levels.
Although instruments such as IPAQ are useful for surveillance, there was
a need for a simple quick assessment tool that can be used in primary care
to identify inactive individuals as part of the assessment of risk. The
short version of the EPIC-Europe questionnaire that was validated by
comparison to repeated measures of objectively assessed energy expenditure
(Wareham et al, Public Health Nutrition 2003) has formed the basis of the
General Practice Physical Activity Questionnaire (GPPAQ) recommended by
the Department of Health (3) as a screening tool to be used in routine
general practice to provide a simple physical activity index. The validity
of the instrument provides one justification for its use, but the
Department of Health report also cites the evidence from the Unit's
research showing that this simple tool independently predicts events such
as cardiovascular incidence and mortality (Khaw et al, Int J Epidemiol
2006).
The MRC Epidemiology Unit's research on physical activity, sedentary
behaviour and different outcomes has contributed to the recent revision of
the UK Chief Medical Officers' recommendation on physical activity (4)
with the work in adults ( Ekelund et al, Am J Clin Nutr 2008) and children
(Steele et al, Am J Clin Nutr 2009) being cited in the review of the
current scientific evidence relating sedentary behaviour to obesity (5)
which was undertaken as part of the work leading to the formulation of the
new guidelines which place a greater emphasis on the avoidance of
prolonged periods of sedentary time.
A number of pieces of NICE Public Health guidance have emerged over the
past 5 years aimed at describing the effectiveness of different approaches
to promoting physical activity. The NICE Public Health Guidance (6) on
physical activity and the environment cites the Unit's analysis of
temporal trends in physical activity in the United Kingdom (Stamatakis et
al, 2007). The more recent guidance on promoting walking and cycling (7)
cites the Unit's systematic review of interventions to promote cycling
(Yang et al, BMJ 2010) in the supporting evidence for the guidance
including Expert Testimony Paper 5 —Programmes to promote cycling. The
recommendations for future research in this guidance draw heaving on
Expert Testimony Paper 3 which cites multiple publications from CEDAR to
demonstrate an approach to the evaluation of infrastructure developments
which have the potential to integrated walking and cycling into people's
daily routines. This includes the evaluation of interventions such as
CONNECT2, a SUSTRANS project funded by the Big Lottery Fund to transform
everyday travel for local people in communities across the UK, creating
new bridges and crossings to overcome busy roads, rivers and railways, and
linking these to networks of walking and cycling routes, making it easier
for millions of people to walk and cycle for everyday journeys (8).
Evaluations of this type are able to demonstrate impact of overall and
domain-specific physical activity levels but are unlikely to be able to
demonstrate an impact on health outcomes, which need to be modelled rather
than directly observed (Jarrett et al, Lancet 2012). The papers describing
the results of these models have contributed to analyses not only of the
benefits of promoting physical activity on health outcomes but are cited
in more extensive analyses of the health effects of climate change (9)
since physical activity, transportation, energy use, pollution and climate
change are closely linked issues.
Sources to corroborate the impact
- Diet and physical activity toolkit. The Medical Research Council. http://www.dapa-toolkit.mrc.ac.uk/
(Last accessed 5th September 2013).
- Measuring diet and physical activity in weight management programmes.
National Obesity Observatory.
http://www.noo.org.uk/uploads/doc/vid_10414_Assessment%20Tools%20160311%20FINAL%20MG.pdf
- General Practice Physical Activity Questionnaire. Department of
Health.
https://www.gov.uk/government/publications/general-practice-physical-activity-questionnaire-gppaq
- UK Physical Activity Guidelines. Department of Health. Sedentary
Behaviour and Obesity. Review of the current scientific evidence.
Department of Health.
https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/213745/dh_128225.pdf
- Physical activity and the Environment. NICE.
http://www.nice.org.uk/nicemedia/live/11917/38983/38983.pdf
- Walking and cycling: local measures to promote walking and cycling as
forms of travel or recreation. NICE. http://www.nice.org.uk/nicemedia/live/13428/58979/58979.pdf
and http://www.nice.org.uk/nicemedia/live/13428/58977/58977.pdf
- Working with the research community. SUSTRANS. http://www.sustrans.org.uk/our-services/who-we-work/researchers
- Health effects of climate change in the UK 2012. Public Health
England. http://www.hpa.org.uk/hecc2012