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Featured researches published by Jenna L. Hollis.


British Journal of Sports Medicine | 2016

'Physical Activity 4 Everyone' school-based intervention to prevent decline in adolescent physical activity levels: 12 month (mid-intervention) report on a cluster randomised trial

Rachel Sutherland; Elizabeth Campbell; David R. Lubans; Philip J. Morgan; Anthony D. Okely; Nicole Nathan; Luke Wolfenden; Jarrod S Wiese; Karen Gillham; Jenna L. Hollis; John Wiggers

Background Adolescence is a recognised period of physical activity decline, particularly among low-income communities. We report the 12-month (midpoint) effects of a 2-year multicomponent physical activity intervention implemented in disadvantaged secondary schools. Methods A cluster randomised trial was undertaken in 10 secondary schools located in disadvantaged areas in New South Wales, Australia. Students in Grade 7 were recruited, with follow-up in Grade 8. The intervention was guided by socioecological theory and included seven physical activity strategies, and six implementation adoption strategies. The primary outcome was mean minutes of moderate-to-vigorous physical activity (MVPA) per day assessed using Actigraph GT3X accelerometers. Outcome data were analysed using repeated measures linear mixed models. Results At baseline, 1150 (93%) students participated in the data collection (mean age 12 years, 48% boys) and 1050 (79%) students participated at 12-month follow-up. By the 12-month follow-up, the six implementation adoption strategies had been used to support schools to deliver four of the seven physical activity elements. There was a significant group-by-time interaction for mean minutes of MVPA per day in favour of the intervention group (adjusted difference between groups at follow-up=3.85 min, 95% CI (0.79 to 6.91), p≤0.01), including significantly more vigorous physical activity (2.45 min, p≤0.01), equating to 27 min more MVPA per week. Summary At 12-month follow-up, the intervention had reduced the decline in physical activity among adolescents from disadvantaged schools. The intervention may assist students to meet physical activity guidelines.


Implementation Science | 2015

Effectiveness of an intervention to facilitate the implementation of healthy eating and physical activity policies and practices in childcare services: a randomised controlled trial

Jannah Jones; Rebecca Wyse; Meghan Finch; Christophe Lecathelinais; John Wiggers; Josephine Marshall; Maryann Falkiner; Nicole Pond; Sze Lin Yoong; Jenna L. Hollis; Alison Fielding; Pennie Dodds; Tara Clinton-McHarg; Megan Freund; Patrick McElduff; Karen Gillham; Luke Wolfenden

BackgroundThe primary aim of this study was to evaluate the effectiveness of an intervention to increase the implementation of healthy eating and physical activity policies and practices by centre-based childcare services. The study also sought to determine if the intervention was effective in improving child dietary intake and increasing child physical activity levels while attending childcare.MethodsA parallel group, randomised controlled trial was conducted in a sample of 128 childcare services. Intervention strategies included provision of implementation support staff, securing executive support, staff training, consensus processes, academic detailing visits, tools and resources, performance monitoring and feedback and a communications strategy. The primary outcome of the trial was the proportion of services implementing all seven healthy eating and physical activity policies and practices targeted by the intervention. Outcome data were collected via telephone surveys with nominated supervisors and room leaders at baseline and immediately post-intervention. Secondary trial outcomes included the differences between groups in the number of serves consumed by children for each food group within the Australian Guide to Healthy Eating and in the proportion of children engaged in sedentary, walking or very active physical activity assessed via observation in a random subsample of 36 services at follow-up.ResultsThere was no significant difference between groups for the primary trial outcome (p = 0.44). Relative to the control group, a significantly larger proportion of intervention group services reported having a written nutrition and physical activity policy (p = 0.05) and providing adult-guided activities to develop fundamental movement skills (p = 0.01). There were no significant differences between groups at follow-up on measures of child dietary intake or physical activity.ConclusionsThe findings of the trial were equivocal. While there was no significant difference between groups for the primary trial outcome, the intervention did significantly increase the proportion of intervention group services implementing two of the seven healthy eating and physical activity policies and practices. High levels of implementation of a number of policies and practices at baseline, significant obesity prevention activity in the study region and higher than previously reported intra-class correlation of child behaviours may, in part, explain the trial findings.Trial registrationAustralian Clinical Trials Registry (reference ACTRN12612000927820).


Nutrition & Diabetes | 2014

Can a relatively low-intensity intervention by health professionals prevent weight gain in mid-age women? 12-Month outcomes of the 40-Something randomised controlled trial

Lauren Williams; Jenna L. Hollis; Clare E. Collins; Philip J. Morgan

Background:Weight gain in perimenopausal women results in increased visceral adipose tissue, leading to metabolic syndrome and associated comorbidities. Despite a high prevalence of weight gain at this life stage, interventions to prevent menopausal obesity are lacking.Aim:To test the effectiveness of an intervention delivered by health professionals using a motivational interviewing (MI) counselling style in preventing weight gain in non-obese (body mass index (BMI) 18.5 and 29.9 kg m−2) women in late premenopause.Methods:In a randomised controlled trial, 54 women (mean (s.d.) age 47.3 (1.8) years; BMI 25.1 (2.4) kg m−2) who had menstruated within the preceding 3 months were randomly assigned to an MI intervention (n=28) (five health professional MI counselling sessions) or a self-directed intervention (SDI) (print materials only) (n=26). The primary outcome, body weight (kg) and secondary outcomes (blood lipids, glucose, body fat %, lean mass % and waist circumference) were measured at baseline and postintervention (12 months), and intention-to-treat analysis was conducted.Results:Forty women completed all measures and adhered to all protocols. The weight at 12 months for the MI group of 65.6 kg (95% CI: 64.5; 66.8) was significantly different (P=0.034) from the SDI group of 67.4 kg (95% CI: 66.2; 68.6). When stratified by baseline BMI category, the MI group lost significantly more weight (−2.6 kg; 95% CI: −3.9; −1.2) than the SDI group (−0.1 kg; 95% CI: −1.2; 1.0, P=0.002) for the healthy weight women. The overweight women lost weight regardless of the intervention group, with no between-group difference (−3.5 kg; 95% CI: −6.1, −1.0 and −2.3; 95% CI: −4.1, −0.5, P=0.467).Conclusion:This relatively low-intensity intervention, incorporating MI into health professional counselling, not only effectively prevented weight gain but also achieved significant weight loss and decreased diastolic blood pressure. Further refinements are required to optimise outcomes for overweight women.


International Journal of Behavioral Nutrition and Physical Activity | 2017

A systematic review and meta-analysis of moderate-to-vigorous physical activity levels in secondary school physical education lessons

Jenna L. Hollis; Rachel Sutherland; Amanda Williams; Elizabeth Campbell; Nicole Nathan; Luke Wolfenden; Philip J. Morgan; David R. Lubans; Karen Gillham; John Wiggers

BackgroundSchools play an important role in physical activity promotion for adolescents. The systematic review aimed to determine the proportion of secondary (middle and high) school physical education (PE) lesson time that students spend in moderate to vigorous physical activity (MVPA), and to assess if MVPA was moderated by school level (middle and high school), type of physical activity measurement and type of PE activities.MethodsA systematic search of nine electronic databases was conducted (PROSPERO2014:CRD42014009649). Studies were eligible if they were published between 2005 and 2014; written in English; assessed MVPA in PE lessons of secondary (middle and high) school students; and used a quantitative MVPA measure (i.e., accelerometry, heart rate monitoring, pedometers or observational measures). Two reviewers examined the retrieved articles, assessed risk of bias, and performed data extraction. Random effects meta-analysis was used to calculate a pooled estimate of the percent of PE lesson time spent in MVPA and to assess moderator effects where data allowed.ResultsThe search yielded 5,132 potentially relevant articles; 28 articles representing 25 studies (7 middle and 18 high school) from seven countries were included. Twelve studies measured MVPA through observational measures, seven used accelerometers, five used heart rate monitors and four used pedometers (including three studies using a mix of measures). Meta-analysis of 15 studies found that overall, students spent a mean (95% CI) of 40.5% (34.8–46.2%) of PE in MVPA. Middle school students spent 48.6% (41.3–55.9%) of the lesson in MVPA (n = 5 studies) and high school students 35.9% (28.3–43.6%) (n = 10 studies). Studies measuring MVPA using accelerometers (n = 5) showed that students spent 34.7% (25.1–44.4%) of the lesson in MVPA, while 44.4% (38.3–50.5%) was found for lessons assessed via observation (n = 9), 43.1% (24.3–61.9%) of the lesson for a heart rate based study, and 35.9% (31.0–40.8%) for a pedometer-measured study.ConclusionsThe proportion of PE spent in MVPA (40.5%) is below the US Centre for Disease Control and Prevention and the UK Associations for Physical Education recommendation of 50%. Findings differed according to the method of MVPA assessment. Additional strategies and intervention research are needed to build more active lesson time in PE.


Journal of the Academy of Nutrition and Dietetics | 2014

Does Motivational Interviewing Align with International Scope of Practice, Professional Competency Standards, and Best Practice Guidelines in Dietetics Practice?

Jenna L. Hollis; Lauren Williams; Clare E. Collins; Philip J. Morgan

This article was written by Jenna L. Hollis, APD*, a doctoral degree candidate, Nutrition and Dietetics, School of Health Sciences, Faculty of Health and Medicine, and the Priority Research Centre in Physical Activity and Nutrition, The University of Newcastle, Callaghan, New South Wales, Australia; Lauren T. Williams, PhD, AdvAPD*, a professor and head, Discipline of Nutrition and Dietetics, School of Public Health, Griffith University, Southport, Queensland, Australia, and an adjunct professor of nutrition and dietetics, Nutrition and Dietetics Department, Faculty of Health, The University of Canberra, Bruce, Australian Capital Territory, Australia; Clare E. Collins, PhD, AdvAPD, FDAA*, a professor, Nutrition and Dietetics, a National Health and Medical Research Council Career Development Fellowship research fellow, and codirector, Priority Research Centre in Physical Activity and Nutrition, Faculty of Health and Medicine, The University of Newcastle, Callaghan, New South Wales, Australia; and Philip J. Morgan, PhD, a professor and codirector, Priority Research Centre in Physical Activity and Nutrition, Faculty of Education and Arts, University of Newcastle, Callaghan, New South Wales, Australia.


International Journal of Evidence-based Healthcare | 2012

Effectiveness of interventions using Motivational Interviewing for dietary and physical activity modification in adults: A Systematic Review

Jenna L. Hollis; Lauren Williams; Clare E. Collins; Philip J. Morgan

Background When healthcare professionals are confronted with ambivalence in their clients, traditional advice‐giving can be counter‐productive. Motivational Interviewing (MI), an alternative to traditional advice‐giving, aims to provide the ambivalent client with a supportive, non‐judgmental environment in which to discuss the possibility of change. Objectives This review aimed to synthesize the best available evidence on the effectiveness of dietary and physical activity interventions employing MI to achieve behavior change. Inclusion criteria Types of participants The review included participants aged 18 years or older. Types of intervention(s)/phenomena of interest Studies that defined the intervention as ‘Motivational Interviewing’ and provided detail on how MI was incorporated into the studies were included. The included studies separated subjects into one group receiving the MI intervention and one group receiving a comparison treatment with similar contact but without MI counseling (an attention control). Types of studies The review considered randomized controlled trials (RCT) or systematic reviews published in English between 1980 to January 2012 Types of outcomes Outcomes of interest included diet (energy intake, core food groups, macronutrient composition of the diet, diet quality or diet index) and/or physical activity including exercise or sedentary behaviors (energy expenditure, steps taken, minutes of physical activity or sitting time). Search strategy Nine databases were searched and the reference lists of all included studies were searched for additional studies not previously identified. Methodological quality Two independent reviewers used a standardized appraisal tool to ensure the methodological quality of the studies. Data collection Two reviewers performed data extraction using a standardized tool. Data synthesis A qualitative synthesis was undertaken through a comparative narrative summary. Results The search yielded 1,765 articles of which eight met all inclusion criteria. The review reported on a heterogeneous sample of studies that were of low‐to‐moderate quality. Five of the studies reported monitoring MI fidelity; however only three studies reported proficiency scores. Two of the five articles reporting on diet found positive effects. One study found a lower saturated fat score in the group that received MI by a dietician (&bgr;=0.23, &rgr;<0.01) compared with counseling by a dietician not trained in MI. The other study reported a significant difference in percent energy from fat (2.6%, &rgr;<0.001) favoring Motivational Interviewing when comparing Motivational Interviewing from a dietician versus standard care. None of the six articles reporting on physical activity found any difference between MI and the attention control. Conclusions There is not yet sufficient evidence to conclude that MI enhances diet and physical activity behavior change above an attention control, although the findings from two studies are suggestive of a positive effect in decreasing dietary fat intake. Implications for practice When more high quality research evidence is available, the next challenge will be to establish evidence that research‐based interventions will translate to the clinical setting. Implications for research More high quality studies that objectively measure diet and physical activity, evaluate and report fidelity scores and compare a MI intervention to an attention control over a period of at least six months are required.


Public Health Nutrition | 2017

Assessing the relative validity of the Scottish Collaborative Group FFQ for measuring dietary intake in adults

Jenna L. Hollis; L. C. A. Craig; Stephen Whybrow; Heather Clark; Janet Kyle; Geraldine McNeill

OBJECTIVE To assess the relative validity of the latest version of the Scottish Collaborative Group (SCG) FFQ (version 6.6) in adults living in Scotland. DESIGN A cross-sectional validation study. Participants completed the self-administered, 169-item SCG FFQ followed by a 7 d, non-weighed food diary. Energy and energy-adjusted macronutrients and micronutrients were examined for relative validity through Spearmans correlation, the percentage of classification into thirds of intake, Cohens weighted kappa (κ w) and Bland-Altman analysis. SETTING General population living in Scotland. SUBJECTS Ninety-six adults aged 18-65 years. RESULTS Spearmans correlation coefficients ranged from 0·21 (retinol) to 0·71 (Mg). A median of 52 % of adults were correctly classified into thirds of intake (range: 42 % (PUFA, MUFA and Fe) to 64 % (percentage energy from carbohydrates)) and 8 % were grossly misclassified into opposite thirds of intake (range: 3 % (carbohydrates, percentage energy from carbohydrates) to 19 % (thiamin)). Values of κ w ranged between 0·20 (PUFA, β-carotene) to 0·55 (percentage energy from carbohydrates). In the Bland-Altman analysis, the smallest limits of agreement, when expressed as a percentage of the mean intake from the FFQ and food diary, were seen for the main macronutrients carbohydrates, fat and protein. CONCLUSIONS As in the previous validation study more than 10 years ago, the FFQ gave higher estimates of energy and most nutrients than the food diary, but after adjustment for energy intake the FFQ could be used in place of non-weighed food diaries for most macronutrients and many micronutrients in large-scale epidemiological studies.


International Journal of Obesity | 2016

Effects of a ‘school-based’ physical activity intervention on adiposity in adolescents from economically disadvantaged communities: secondary outcomes of the ‘Physical Activity 4 Everyone’ RCT

Jenna L. Hollis; Rachel Sutherland; Libby Campbell; Philip J. Morgan; David R. Lubans; Nicole Nathan; Luke Wolfenden; Anthony D. Okely; Lynda Davies; Amanda C. de C. Williams; Kristen E. Cohen; Christopher Oldmeadow; Karen Gillham; John Wiggers

BACKGROUND/OBJECTIVES:Obesity prevention during adolescence is a health priority. The ‘Physical Activity 4 Everyone’ (PA4E1) study tested a multi-component physical activity intervention in 10 secondary schools from socio-economically disadvantaged communities. This paper aimed to report the secondary outcomes of the study; to determine whether the intervention impacted on adiposity outcomes (weight, body mass index (BMI), BMI z-score), and whether any effect was moderated by sex, baseline BMI and baseline physical activity level, at 12 and 24 months.SUBJECTS/METHODS:A cluster randomised controlled trial was conducted in New South Wales, Australia. The school-based intervention included seven physical activity strategies targeting the following: curriculum (strategies to maximise physical activity in physical education, student physical activity plans, an enhanced school sport programme); school environment (physical activity during school breaks, modification of school policy); and parents and the community (parent engagement, links with community physical activity providers). Students’ weight (kg), BMI and BMI z-score, were collected at baseline (Grade 7), 12 and 24 months. Linear Mixed Models were used to assess between-group mean difference from baseline to 12 and 24 months. Exploratory sub-analyses were undertaken according to three moderators of energy balance.RESULTS:A total of 1150 students (mean age=12 years) provided outcome data at baseline, 1051 (91%) at 12 months and 985 (86%) at 24 months. At 12 months, there were group-by-time effects for weight (mean difference=–0.90 kg (95% confidence interval (CI)=–1.50, −0.30), P<0.01) and BMI (−0.28 kg m−2 (−0.50, −0.06), P=0.01) in favour of the intervention group, but not for BMI z-score (−0.05 (−0.11; 0.01), P=0.13). These findings were consistent for weight (−0.62 kg (−1.21, 0.03), P=0.01) and BMI (−0.28 kg m−2 (−0.49, −0.06), P=0.01) at 24 months, with group-by-time effects also found for BMI z-score (−0.08 (−0.14; −0.02), P=0.02) favouring the intervention group.CONCLUSION:The PA4E1 school-based intervention achieved moderate reductions in adiposity among adolescents from socio-economically disadvantaged communities. Multi-component interventions that increase adolescents’ engagement in moderate-to-vigorous physical activity (MVPA) may assist in preventing unhealthy weight gain.


Appetite | 2014

Compliance to step count and vegetable serve recommendations mediates weight gain prevention in mid-age, premenopausal women. Findings of the 40-Something RCT.

Jenna L. Hollis; Lauren Williams; Myles D. Young; Katherine T. Pollard; Clare E. Collins; Philip J. Morgan

The 40-Something RCT aimed to determine if a 12-month health professional-led intervention could modify diet and physical activity behaviour for obesity prevention, in 44-50 year old, non-obese (BMI = 18.5-29.9 kg/m(2)) premenopausal women. Women were monitored for an additional 12 months to determine if effects could be maintained. This paper aimed to explore dietary and physical activity behavioural mediators hypothesised to be causally associated with weight change. Fifty-four women were randomised to a Motivational Interviewing Intervention (MI) (n = 28; five health professional consultations) or a Self-Directed Intervention (n = 26; written advice). Compliance to 10 study recommendations was measured at three months by a four-day weighed food and physical activity record including pedometer-measured step counts, self-reported exercise minutes and sitting time. The 10 compliance scores were independently assessed in mediation models for 12- and 24-month weight change. The MI effect on step count was an increase of 0.99 points on the 10-point compliance scale (p ≤ 0.01). This MI effect on step count significantly mediated the 12 and 24 month effect on weight (12 months AB = -0.74, 95%CI = -1.95, -0.14; 24 months AB = -1.06, 95% CI = -2.56, -0.36), accounting for 37.23% and 53.79% of the effect, respectively. The MI effect on vegetable serves was an increase of 1.50 points on the compliance scale (p = 0.02). The MI effect on vegetable compliance significantly mediated the effect on weight at 24 months (AB = -0.54, 95% CI = -1.50, -0.04), accounting for 24.92% of the effect. The remaining eight dietary and physical activity compliance scores did not significantly mediate weight loss. Encouraging women to take 10,000 steps and eat five vegetable serves per day may be a promising strategy to achieve long-term weight control at mid-life.


International Journal of Obesity | 2017

Modifiable risk factors of maternal postpartum weight retention: an analysis of their combined impact and potential opportunities for prevention.

Jenna L. Hollis; Sarah Crozier; Hazel Inskip; C Cooper; Keith M. Godfrey; Nicholas C. Harvey; Clare E. Collins; Sian Robinson

Background/Objectives:Pregnancy triggers a physiological change in weight status. Postpartum weight retention in the childbearing years can substantially alter a woman’s weight gain trajectory, with several potential contributing factors identified. Most research has relied on women’s recall of pre-pregnancy weight during pregnancy or later, and not considered risk factors in combination. Using measured pre-pregnancy weight, this study aimed to examine the associations of maternal postpartum weight retention with parity, pre-pregnancy BMI, excessive gestational weight gain (GWG), maternal serum vitamin D concentration and dietary Glycaemic Index in early and late pregnancy, and breastfeeding duration, including analysis of the combined impact of potentially modifiable risk factors.Subjects/Methods:Prospective cohort study of 12 583 non-pregnant women aged 20–34 years in Southampton (UK) who were assessed prior to pregnancy, with those who subsequently became pregnant followed up in early and late gestation, and after delivery (n=2559 in the final sample). Linear regression models examined potential predictors of weight retention in adjusted individual and multivariate analyses, and as a risk factor score.Results:Compared with pre-pregnancy weight, 73% of women retained some weight at 6 months postpartum (mean (s.d.): 3.5 (6.2) kg). In the adjusted multivariate model, women who were primiparous, had a lower pre-pregnancy BMI, excessive GWG, a lower early pregnancy vitamin D concentration and breastfed for <6 months had greater weight retention 6 months postpartum (P<0.05 for all variables). For each additional modifiable risk factor (excessive GWG, low vitamin D concentration in early pregnancy and short breastfeeding duration; scale 0–3), women retained an additional 2.49 kg (95% CI: 2.16, 2.82; P<0.001).Conclusions:Having a greater number of modifiable risk factors was associated with greater weight retention 6 months postpartum. Initiatives supporting women to target these risk factors in the years prior to, during and after pregnancy could impact on their weight gain trajectory and later risk of adverse weight-related outcomes.

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John Wiggers

University of Newcastle

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