Jennifer D. Irwin

Jennifer D. Irwin


Research Focus & Metrics

Academic Career Length

23Years (2004-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 June 2004 in Perceptual and Motor Skills
Verified
Journal Article
Closed access
JIJennifer D. Irwin
Jennifer D. Irwin
This study reviewed and analyzed the prevalence of university students' participation in physical activity at the level necessary to acquire health benefits. 19 primary studies (published 1985–2001) representing a total of 35,747 students (20,179 women and 15,568 men) from a total of 27 countries (Australia, Canada, China, Germany, Nigeria, United States, and 21 European countries) are described and the amount of activity identified within each study is analyzed in accordance with the American College of Sports Medicine (ACSM) guidelines for physical activity. With respect to these guidelines, more than one-half of university students in the United States and Canada are not active enough to gain health benefits. Internationally, the same is true, although Australian students appear to have the highest level of sufficient activity (at 60%). Women, and especially African-American women, are among the least active students, and students living off-campus are more active than those on-campus. Insufficient activity is a serious health concern among university students. Appropriate interventions and tools to measure ACSM-recommended physical activity are needed.

LVLeigh M Vanderloo
Leigh M Vanderloo
TTTrish Tucker
Trish Tucker
AJAndrew Johnson
Andrew Johnson
MZMelissa M. Van Zandvoort
Melissa M. Van Zandvoort
SBShauna Burke
Shauna Burke
JIJennifer D. Irwin
Jennifer D. Irwin
The childcare environment represents an appropriate avenue to support physical activity among preschoolers. The aim of this study was two-fold: (1) to measure the physical activity levels of a sample of preschoolers during childcare hours; and (2) to assess which attributes (e.g., space, equipment, policies) within centre-based childcare environments influenced physical activity. Thirty-one preschoolers from 5 childcare centres across London, Canada participated. Actical accelerometers were worn by participants for one day during childcare hours to assess activity levels using a 15 second epoch length. The Environment and Policy Assessment and Observation instrument was used to conduct a full-day evaluation of the childcare environment. On average, participants engaged in 1.54 min/h of moderate-to-vigorous physical activity and 17.42 min/h of total physical activity. Sedentary opportunities, portable and fixed play equipment, and staff behaviour accounted for 49.3% of the variability in moderate-to-vigorous physical activity and 14.1% of the variability in total physical activity, with sedentary opportunities, fixed play equipment, and staff behaviours displaying an inverse relationship. Results emphasize the critical role the childcare environment plays in supporting physical activity among preschoolers.

MHMeizi He
Meizi He
TTTrish Tucker
Trish Tucker
JGJason Andrew Gilliland
Jason Andrew Gilliland
JIJennifer D. Irwin
Jennifer D. Irwin
Kristian LarsenKristian Larsen
Kristian Larsen
PHPaul Hess
Paul Hess
This study examined the relationship between the neighborhood food environment and the food purchasing behaviors among adolescents. Grade 7 and 8 students (n = 810) at 21 elementary schools in London, Ontario, Canada completed a questionnaire assessing their food purchasing behaviors. Parents of participants also completed a brief questionnaire providing residential address and demographic information. A Geographic Information System (GIS) was used to assess students’ home and school neighborhood food environment and land use characteristics. Logistic regression analysis was conducted to assess the influence of the home neighborhood food environment on students’ food purchasing behaviors, while two-level Hierarchical Non-Linear Regression Models were used to examine the effects of school neighborhood food environment factors on students’ food purchasing behaviors. The study showed that approximately 65% of participants reported self-purchasing foods from fast-food outlets or convenience stores. Close proximity (i.e., less than 1 km) to the nearest fast-food outlet or convenience store in the home neighborhood increased the likelihood of food purchasing from these food establishments at least once per week by adolescents (p < 0.05). High fast-food outlet density in both home and school neighborhoods was associated with increased fast-food purchasing by adolescents (i.e., at least once per week; p < 0.05). In conclusion, macro-level regulations and policies are required to amend the health-detracting neighborhood food environment surrounding children and youth’s home and school.

1 July 2005 in Canadian Journal of Public Health
Verified
Journal Article
Closed access
PDF file
JIJennifer D. Irwin
Jennifer D. Irwin
MHMeizi He
Meizi He
LBL. Michelle Sangster Bouck
L. Michelle Sangster Bouck
PTPatricia Tucker
Patricia Tucker
GPGraham L. Pollett
Graham L. Pollett

15 November 2011 in BMC Research Notes
Verified
Journal Article
Open access
PDF file
HTHeather MC Thomas
Heather MC Thomas
JIJennifer D. Irwin
Jennifer D. Irwin
In Canada, there are limited occasions for youth, and especially at-risk youth, to participate in cooking programs. The paucity of these programs creates an opportunity for youth-focused cooking programs to be developed, implemented, and evaluated with the goal of providing invaluable life skills and food literacy to this potentially vulnerable group. Thus, an 18-month community-based cooking program for at-risk youth was planned and implemented to improve the development and progression of cooking skills and food literacy.

7 September 2017 in International Journal of Behavioral Nutrition and Physical Activity
Verified
Journal Article
Open access
PDF file
TTTrish Tucker
Trish Tucker
LVLeigh M Vanderloo
Leigh M Vanderloo
AJAndrew Johnson
Andrew Johnson
SBShauna Burke
Shauna Burke
JIJennifer D. Irwin
Jennifer D. Irwin
BTBrian Timmons
Brian Timmons
Physical activity levels among preschoolers in childcare are low and sedentary time high. The Supporting Physical Activity in the Childcare Environment (SPACE) intervention had three components: 1. portable play equipment; 2. staff training; and, 3. modified outdoor playtime (i.e., shorter, more frequent periods). This study aimed to examine the effectiveness of the SPACE intervention on preschoolers’ physical activity levels and sedentary time during childcare hours (compared to standard care). Via a single-blind cluster randomized controlled trial, 338 preschoolers (39.86 ± 7.33 months; 52% boys) from 22 centre-based childcare facilities (11 experimental, 11 control) were enrolled. Preschoolers wore an Actical™ accelerometer for 5 days during childcare hours at baseline, post-intervention, and 6- and 12-month follow-up, and were included in the analyses if they had a minimum of two valid days (5 h each day) at baseline and one additional time point. Intervention effectiveness was tested using a linear mixed effects model for each of the four outcome variables (i.e., sedentary time, light physical activity [LPA], moderate-to-vigorous physical activity [MVPA], and total physical activity [TPA]). Fixed effects were further evaluated with t-tests, for which degrees of freedom were estimated using a Satterthwaite approximation. One hundred and ninety-five preschoolers were retained for analyses. The intervention did not significantly impact LPA. MVPA was significantly greater among children in the experimental group when comparing post-intervention to pre-intervention, t(318) = 3.50, p = .0005, but no intervention effects were evident at 6- or 12-month follow-up. TPA was significantly greater for children in the intervention group at post-intervention when compared to pre-intervention, t(321) = 2.70, p = .007, with no intervention effects evident at later time periods. Finally, sedentary time was significantly lower among preschoolers in the experimental group when comparing post-intervention to pre-intervention, t(322) = 2.63, p = .009, with no significant effects at follow-up. The SPACE intervention was effective at increasing MVPA and TPA among preschoolers, while simultaneously decreasing sedentary time. The ability of the SPACE intervention to target higher intensity activity is promising, as MVPA levels have been documented to be low in centre-based childcare. The changes in physical activity were not sustained long term (6- or 12-month follow-up). ISRCTN70604107 (October 8, 2014).