Appendix V - Physical activity NI Report NDNS 2019-2023
Source: data.gov.uk (2025-10-10)

National Diet and Nutrition Survey 2017 to 2023 Report for Northern Ireland. This report presents results from 2017-2023 of the National Diet and Nutrition Survey (NDNS) for Northern Ireland. NDNS is a continuous cross-sectional survey, designed to assess the diet, nutrient intake and nutritional status of the general population aged 18 months and over living in private households in the UK.

National Diet and Nutrition Survey. Years 10 to 15 of the Rolling Programme for Northern Ireland 
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Appendix V Physical activity assessment  
V.1 Recent Physical Activity Questionnaire (RPAQ) 
 
Participants aged 16 years and over were invited to complete a physical activity 
assessment using the Recent Physical Activity Questionnaire (University of 
Cambridge Physical Activity Downloads). The RPAQ, a self-completion 
questionnaire, is designed to assess an individual’s physical activity over the 
previous 4 weeks and contains questions about physical activity in 4 domains: at 
home, at work, during commuting and during leisure time.  
The RPAQ has been validated against doubly labelled water (DLW) and individually 
calibrated heart rate and movement sensing to assess physical activity energy 
expenditure (PAEE) in adults.i,ii 
The RPAQ has been included in NDNS since year 2 (2009) with some minor 
adaptations and variations in questions between years. In years 2 to 11 (2009 to 
2019), the RPAQ information was collected via a paper questionnaire. From year 12 
(2019) the RPAQ moved to an online version. Television watching and computer use 
were separate questions in the paper version whereas in the online version a single 
question was asked about overall screen time to better reflect current screen use 
habits. Variables for other household activities (e.g. vacuuming), skiing and active 
computer games were added to the online version. None of the changes between 
the paper and online versions affect the calculation of PAEE. 
Further changes made to the online version since it was introduced were as follows:  
• adaptation to improve optimisation for with smaller screens  
• from year 13, the work section of the questionnaire was amended to 
specifically include education (as the questionnaire could be completed by 
those aged 16 to 18 years who were still in full time education and not 
working)  
The RPAQ version used in years 14 and 15 is provided in appendix F (earlier 
versions are available on request). 
 
V.1.1 Calculating energy expenditure from physical activity 
 
Total PAEE was calculated by summing PAEE for all activities across all domains. 
Total PAEE was expressed in kilojoules per kilogram of body weight per 
day (kJ/kg/day) where 1 metabolic equivalent (MET) equates to 71.2 J/min/kg (3.5 ml 
O2/min/kg).  
To compute PAEE from the RPAQ, reported time spent on activities was multiplied 
by the metabolic cost of each activity (in metabolic equivalents, METs) obtained from 
the physical activity compendiumiii,iv minus 1 MET for resting metabolic rate, to 

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provide activity-specific PAEE estimates.i Variables household (e.g. vacuuming), 
skiing and active computer games were removed from output variables to ensure 
harmonisation to earlier RP years  
Modifications to this scoring regime were made for occupational activity which 
was quantified according to the approach outlined by Golubic and othersii and 
derived from a cohort of 12,435 UK adults in the Fenland Study who had completed 
the RPAQ concurrently with objective assessment of PAEE, estimated 
from individually calibrated combined heart rate and movement sensing.v The 
average intensity estimates for reported work duration were 1.54 METs for sedentary 
occupations, 1.74 METs for standing occupations, 1.93 METs for manual work, and 
2.20 METs for heavy manual work. If total reported time spent across all activities 
was greater than 18 hours per day (assuming 6 hours sleep), all reported durations 
of activity were scaled back to 18 hours for that person.  
Total PAEE was calculated for males and females and sex-combined for the age 
groups 16 to 34 years, 35 to 54 years and 55 years and over. These age groups 
were chosen to ensure there were at least 50 participants within each age and sex 
group. 
Descriptive statistics for PAEE in Northern Ireland are presented in Appendix V 
Excel table 1.1 for 2017 to 2023 combined. There are no UK guidelines or 
recommendations for PAEE.  
 
V.2 Child Physical Activity Questionnaires 
Participants aged 5 (or aged 4 and have started school) to 15 years were invited to 
complete a physical activity assessment using the online Child Physical Activity 
Questionnaire (CPAQ). The CPAQ is a self-completion questionnaire designed to 
assess a child’s individual physical activity over the last 7 days (University of 
Cambridge Physical Activity Downloads). It contains questions about physical activity 
in 2 domains: school and out of school, alongside time spent sitting. The CPAQ has 
been used in the NDNS RP since year 12 and was adapted by the Epidemiology 
Unit at the University of Cambridge (Epidemiology Unit) from the questionnaire 
developed for NDNS years 6 to 11 (which was based on questions asked in the 
Health Survey for England). Data from the CPAQ cannot be harmonised with the 
child physical activity questionnaire data collected in NDNS years 6 to 11 due to 
questionnaire differences.   
Since its launch in year 12, small updates have been made to the online CPAQ to 
improve usability and optimisation for small screens. Output variables and response 
options have remained the same.  
The CPAQ was self-completed by participants aged 11 to 15 years and for younger 
children, completed by the parent or guardian. There were small differences in 
question response options for age-appropriateness (e.g. soft play activities appeared 
only for those aged 4 to 10 years and gym or weights and housework only for those 
aged 11 to 15 years). The CPAQ is provided in appendix F. 

National Diet and Nutrition Survey. Years 10 to 15 of the Rolling Programme for Northern Ireland 
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For pre-school children (aged 2 to 4 years) physical activity data was collected using 
a separate questionnaire (see appendix F). Data is not included in the report. More 
detail can be provided on request. 
 
V.2.1 Calculating moderate to vigorous physical activity  
Total moderate to vigorous physical activity (MVPA) time was calculated from CPAQ 
by first assigning any activities to be included. MVPA activities were classified after 
comparison with the Child METs compendiumvi to gain an insight into the given 
energy cost of each activity. Most of the activity variables were included within MVPA 
time calculation. The only variables excluded from this time calculation were:  
• motorised transport to and from school 
• housework 
• any additional activities entered as free text under `Other`  
• sitting  
Once the grouping had been organised, MVPA time for each activity (in minutes) 
was calculated by combining these numbers to get a total MVPA in minutes per day. 
Due to the questionnaire being completed online, no prior data cleaning to the 
variables was required. 
As CPAQ was only introduced in year 12, total MPVA for children aged 4 to 15 in 
Northern Ireland is not presented in this appendix due to small sample sizes. Data 
will be available via the UK Data Service.   
 
 
 
 
 
i Besson H, Brage S, Jakes RW, Ekelund U, Wareham NJ. ‘Estimating physical activity energy 
expenditure, sedentary time, and physical activity intensity by self-report in adults’. American Journal 
of Clinical Nutrition 2010 91(1):106-14  
ii Golubic R, May AM, Benjaminsen Borch K, Overvad K, Charles M-A, Diaz MJT and others. ‘Validity 
of Electronically Administered Recent Physical Activity Questionnaire (RPAQ) in Ten European 
Countries’. PLoS ONE 2014. 9(3): e92829  
iii Ainsworth BE, Haskell WL, Herrmann SD, Meckes N, Bassett DR Jr, Tudor-Locke C, Greer JL, 
Vezina J, Whitt-Glover MC, Leon AS. ‘Compendium of Physical Activities: a second update of codes 
and MET values’. Medicine and Science in Sports and Exercise 2011. 43(8):1575-81) 
iv Ainsworth BE, Haskell WL, Herrmann SD, Meckes N, Bassett Jr DR, Tudor-Locke C, Greer JL, 
Vezina J, Whitt-Glover MC, Leon AS. ‘The Compendium of Physical Activities Tracking Guide’. 
Healthy Lifestyles Research Center, College of Nursing & Health Innovation, Arizona State University  
v Lindsay T, Westgate K, Wijndaele K, Hollidge S, Kerrison N, Forouhi N, Griffin S, Wareham N, 
Brage S. Descriptive epidemiology of physical activity energy expenditure in UK adults (The Fenland 
study). International Journal of Behavorial Nutrition and Physical Activity 2019. 9;16(1):126  
vi Butte NF, Watson KB, Ridley K, et al. A youth compendium of physical activities: activity codes and 
metabolic intensities. 2017; doi: 10.1249/MSS.0000000000001430. Epub 2017 Sep 21. 
 

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