The effects of acute exercise on stress reactivity assessed via a multidimensional approach: a systematic review

Psychological stress is associated with numerous deleterious health effects. Accumulating evidence suggests acute exercise reduces stress reactivity. As stressors activate a wide array of psychological and physiological systems it is imperative stress responses are examined through a multidimensional lens. Moreover, it seems prudent to consider whether stress responses are influenced by exercise intervention characteristics such as modality, duration, intensity, timing, as well as participant fitness/physical activity levels. The current review therefore examined the role of acute exercise on stress reactivity through a multidimensional approach, as well as whether exercise intervention characteristics and participant fitness/physical activity levels may moderate these effects. Stress reactivity was assessed via heart rate, blood pressure, cortisol, catecholamines, and self-report. A systematic search following PRISMA guidelines of five databases was updated in November 2022. Reviewed studies met the following criteria: English language, participants aged ≥ 18, use of acute exercise, use of a validated stress-inducing task, and assessment(s) of stress reactivity. Thirty-one studies (1386 participants) were included. Acute exercise resulted in reliable reductions to blood pressure and cortisol. Acute exercise yielded mostly negligible effects on heart rate reactivity and negligible effects on self-report measures. As for exercise intervention characteristics, intensity-dependent effects were present, such that higher intensities yielded larger reductions to reactivity measures, while limited evidence was present for duration, modality, and timing-dependent effects. Regarding participant fitness/physical activity levels, the effects on stress reactivity were mixed. Future work should standardize the definitions and assessment time points of stress reactivity, as well as investigate the interaction between physiological and psychological stress responses in real-world contexts.

When it comes to sedentary behaviour modification, should people be told what to do? A randomized comparison trial among home-based office workers living in Ontario, Canada

The effects of adding choice architecture to a theory-based (Health Action Process Approach; HAPA) sedentary intervention remain unknown. To investigate whether choice architecture enhances a theory-based sedentary behaviour reduction intervention in home-based office workers. A 4-week HAPA-based intervention was conducted in London, Canada. Choice architecture was tested as an enhancement via a two (group: 'Choice of Intervention' vs. 'No Choice Intervention') by two (time: Baseline vs. Week 4) factorial repeated measure randomized comparison design. Sedentary behaviour reduction strategies focussed on obtaining a sedentary break frequency (BF) of every 30-45 min with break durations (BD) of 2-3 min. BF, BD, sitting, standing, and moving time were objectively measured (activPAL4™) at both time points. Participants (n = 148) were 44.9 ± 11.4 years old and 72.3% female. BF and total sitting time showed a time effect (P < .001), where both groups improved over the 4 weeks; there were no significant differences between groups across time. BD, standing, and moving time had a significant group by time effect where the 'No Choice' group showed significant increases in BD (P < .001), standing (P = .006), and moving time (P < .001) over the 4 weeks. Augmenting a theory-based intervention with choice architecture resulted in change in some sedentary behaviours in at home office workers. Specifically, while BF increased for all participants, the 'No Choice' group exhibited greater changes for BD, standing, and moving time compared with the 'Choice' group. Overall, these changes exceeded the intervention BF and BD goals.

Acute stress negatively impacts on-task behavior and lecture comprehension

Acute stress has been shown to disrupt cognitive and learning processes. The present study examined the effects of acute stress on mind wandering during a lecture and subsequent lecture comprehension in young adults. Forty participants were randomized to acute stress induction via the Trier Social Stress Test or rest prior to watching a twenty-minute video lecture with embedded mind wandering probes, followed by a lecture comprehension assessment. Stress responses were assessed via heart rate, blood pressure, salivary cortisol, and state anxiety. Individuals exposed to acute stress endorsed greater mind wandering at the first checkpoint and lower lecture comprehension scores. Moreover, state anxiety post stress was positively associated with mind wandering at the first and second checkpoint and negatively associated with lecture comprehension. Only mind wandering at the third checkpoint was negatively correlated with overall lecture comprehension. Taken together, these data suggest that acute stress, mind wandering, and lecture comprehension are inextricably linked.

Effect of Lifestyle on Reducing Risk Factors for Type 2 Diabetes among Arab Canadian Muslim Women: A Randomized Control Trial

PURPOSE

This study aimed to investigate whether modifiable risk factors for type 2 diabetes (T2D) can be reduced by an intensive healthy lifestyle intervention designed for Arab Muslim women of Middle Eastern descent (AWMD) who are at high risk for this disease. We hypothesized that among Canadian AWMD, the intervention would (a) reduce the identified health risk factors for T2D (body mass index [BMI], ≥30 kg·m-2; fasting blood glucose [FBG], ≥5.6 mmol·L-1; and waist circumference [WC], ≥80 cm); (b) improve anthropometric measurements; (c) improve lifestyle factors (physical activity level [steps per day] and dietary habits); and (d) improve cardiovascular fitness and reduce blood pressure.

METHODS

After informed consent, 60 participants were randomized to either an exercise and nutrition group (ENG; n = 30) or a control group (CON; n = 30). ENG attended a women-only supervised exercise program that presented Arabic music and traditional Lebanese Dabka three times a week in a Mosque gym for 12 wk. A nutritionist was available 1 h·wk-1 for nutrition education. The CON followed their typical day.

RESULTS

ENG and CON had similar increased risk profiles for diabetes at baseline. Large significant pre/posttreatment interaction effects were found for BMI, FBG, and WC with a reduced diabetes risk for ENG compared with CON for BMI (1,58) = 1184.8, P < 0.001), FBG (1,58) = 187.7, P < 0.001), and WC (1,58) = 326.4, P < 0.001). The ENG had significantly more participants reach postintervention target values (BMI: χ2(1) = 16.48, P = 0.001; FBG: χ2(1) = 52.26, P < 0.001; WC: χ2(1) = 4.29, P = 0.038) compared with the CON. Adherence to the program was 100%.

CONCLUSIONS

Modifiable risk factors for T2D were reduced by using a culturally sensitive intervention program with high adherence through weight loss, regular exercise, and nutrition education.

Exercise behaviors and resource use among graduate students at a Canadian university: A cross-sectional study

OBJECTIVE

Participation in regular exercise among post-secondary students is often low. Our cross-sectional study aimed to assess exercise levels, perceived barriers/motivators to exercise, and knowledge and use of exercise resources in graduate students.

PARTICIPANTS

We recruited graduate students across various disciplines at a large Canadian university.

METHODS

Participants (n = 540) completed an anonymous mixed methods online survey.

RESULTS

Approximately 11% of participants reported not participating in any form of weekly exercise, and only 9.4% met the Canadian Physical Activity Guidelines. The most common barrier and motivator to exercise was time commitment and improving physical health, respectively. Some participants were aware of available exercise services but most did not use them. Suggestions for improving services included having graduate-dedicated exercise space and resources.

CONCLUSIONS

Low exercise participation among graduate students may be due to a lack of education of available resources or a lack of existing resources that meet their specific needs.

Reduction of Financial Health Incentives and Changes in Physical Activity

Importance

Governments and others continue to use financial incentives to influence citizen health behaviors like physical activity. However, when delivered on a population scale they can be prohibitively costly, suggesting more sustainable models are needed.

Objectives

To evaluate the association of incomplete financial incentive withdrawal ("schedule thinning") with physical activity after more than a year of incentive intervention and to explore whether participant characteristics (eg, app engagement and physical activity) are associated with withdrawal outcomes.

Design, Setting, and Participants

This case-control study with a pre-post quasi-experimental design included users of a government-funded health app focused on financial incentives. Eligible participants were residents in 3 Canadian provinces over 25 weeks in 2018 and 2019. Data were analyzed from July 2021 to December 2022.

Exposure

Due to fiscal constraints, financial incentives for daily physical activity goals were withdrawn in Ontario in December 2018 (case)-representing a 90% reduction in incentive earnings-but not in British Columbia or Newfoundland and Labrador (controls).

Main Outcome and Measures

The primary outcome was objectively assessed weekly mean daily step count. Linear regression models were used to compare pre-post changes in daily step counts between provinces (a difference-in-differences approach). Separate models were developed to examine factors associated with changes in daily step count (eg, app engagement and physical activity). Clinically meaningful initial effect sizes were previously reported (approximately 900 steps/d overall and 1800 steps/d among the physically inactive).

Results

In total there were 584 760 study participants (mean [SD] age, 34.3 [15.5] years; 220 388 women [63.5%]), including 438 731 from Ontario, 124 101 from British Columbia, and 21 928 from Newfoundland and Labrador. Significant physical activity declines were observed when comparing pre-post changes in Ontario to British Columbia (-198 steps/d; 95% CI, -224 to -172 steps/d) and Newfoundland and Labrador (-274 steps/d; 95% CI, -323 to -225 steps/d). The decrease was most pronounced for highly engaged Ontario users (-328 steps/d; 95% CI, -343 to -313 steps/d). Among physically inactive Ontario users, physical activity did not decline following withdrawal (107 steps/d; 95% CI, 90 to 124 steps/d).

Conclusions and Relevance

In this case-control study of incomplete financial incentive withdrawal, statistically significant daily step count reductions were observed in Ontario; however, these declines were modest and not clinically meaningful. Amidst substantial program savings, the physical activity reductions observed here may be acceptable to decision-makers working within finite budgets.

Acute stress imparts a transient benefit to task-switching that is not modulated following a single bout of exercise

Introduction

Cognitive flexibility represents a core component of executive function that promotes the ability to efficiently alternate-or "switch"-between different tasks. Literature suggests that acute stress negatively impacts cognitive flexibility, whereas a single bout of aerobic exercise supports a postexercise improvement in cognitive flexibility. Here, we examined whether a single bout of aerobic exercise attenuates a stress-induced decrement in task-switching.

Materials and Methods

Forty participants (age range = 19-30) completed the Trier Social Stress Test (TSST) and were randomized into separate Exercise or Rest groups entailing 20-min sessions of heavy intensity exercise (80% of heart rate maximum via cycle ergometer) or rest, respectively. Stress induction was confirmed via state anxiety and heart rate. Task-switching was assessed prior to the TSST (i.e., pre-TSST), following the TSST (i.e., post-TSST), and following Exercise and Rest interventions (i.e., post-intervention) via pro- (i.e., saccade to veridical target location) and antisaccades (i.e., saccade mirror-symmetrical to target location) arranged in an AABB task-switching paradigm. The underlying principle of the AABB paradigm suggests that when prosaccades are preceded by antisaccades (i.e., task-switch trials), the reaction times are longer compared to their task-repeat counterparts (i.e., unidirectional prosaccade switch-cost).

Results

As expected, the pre-TSST assessment yielded a prosaccade switch cost. Notably, post-TSST physiological measures indicated a reliable stress response and at this assessment a null prosaccade switch-cost was observed. In turn, post-intervention assessments revealed a switch-cost independent of Exercise and Rest groups.

Conclusion

Accordingly, the immediate effects of acute stress supported improved task-switching in young adults; however, these benefits were not modulated by a single bout of aerobic exercise.

A single bout of passive exercise mitigates a mental fatigue-induced inhibitory control deficit

Sustained cognitive effort associated with the psychomotor vigilance task (PVT) increases objective and subjective measures of mental fatigue and elicits a post-PVT inhibitory control deficit. In contrast, passive exercise wherein an individual's limbs are moved via an external force (i.e., mechanically driven cycle ergometer flywheel) provides a postexercise inhibitory control benefit linked to an exercise-based increase in cerebral blood flow. Here, we examined whether passive exercise performed concurrently with the PVT 'blunts' an inhibitory control deficit. On separate days, participants (N = 27) completed a 20 min PVT protocol (control condition) and same duration PVT protocol paired with passive cycle ergometry (passive exercise condition). Prior to (i.e., baseline), immediately after and 30 min after each condition inhibitory control was assessed via the antisaccade task. Antisaccades require a goal-directed eye movement (i.e., saccade) mirror-symmetrical to a target and provide an ideal tool for evaluating task-based changes in inhibitory control. PVT results showed that vigilance (as assessed via reaction time: RT) during control and passive exercise conditions decreased from the first to last 5 min of the protocol and increased subjective ratings of mental fatigue. As well, in the control condition, immediate (but not 30-min) post-intervention antisaccade RTs were longer than their baseline counterparts-a result evincing a transient mental fatigue-based inhibitory control deficit. For the passive exercise condition, immediate and 30-min post-intervention antisaccade RTs were shorter than their baseline counterparts and this result was linked to decreased subjective ratings of mental fatigue. Thus, passive exercise ameliorated the selective inhibitory control deficit associated with PVT-induced mental fatigue and thus provides a potential framework to reduce executive dysfunction in vigilance-demanding occupations.

Tobacco use among varsity athletes - why do they do it and how do we make it stop: a brief report

The current study explores the motivations underlying tobacco use among varsity athletes. A cross-sectional exploratory mixed method approach was used. Both tobacco users (TU) and non-tobacco users (NTU) completed an online survey of closed and open-ended questions. These questions focused on tobacco use, motivations for tobacco use, teammate and coaches' perceptions of athlete tobacco use, and self-perceived effects of tobacco use on health and athletic performance. Thirty-eight completed surveys were included of which 12 were TU and 26 were NTU. The majority of TU indicated that they used products during the off-season. Motivations for using tobacco products included social influences, stress-relief, and increasing energy. TU mostly indicated that there are negative effects on their health but not on their athletic performance, whereas NTU reported potential detrimental effects on their teammate's performance. Overall, varsity athletes who use tobacco products are aware of the health effects and negative opinions of their teammates.

Using a protection motivation theory framework to reduce vaping intention and behaviour in Canadian university students who regularely vape: A randomized controlled trial

Using Protection Motivation Theory (PMT), we examined the effect of threat appraisal information (perceived vulnerability-PV and perceived severity-PS) to reduce vaping intentions, and in turn reduce vaping use. Canadian university students (n = 77) who vape regularly were randomized to either PMT or attention control treatment conditions. Data were collected at baseline and 3 time points after the intervention: Day 7, Day 30, and Day 45. Participants assigned to the PMT group showed significant increases in PV, PS, and intentions to vape less (p ⩽ 0.05) compared to those in the attention control group. Less convincing evidence was found between treatment groups for vaping use. PS and PV predicted vaping intentions, whereas vaping intentions did not predict vaping use. It is suggested through this study that the threat appraisal components of PMT can be successfully manipulated to reduce the intentions to vape and to a lesser extent reduce vaping use among University vapers.

Lessons from zoom-university: Post-secondary student consequences and coping during the COVID-19 pandemic-A focus group study

The COVID-19 pandemic dramatically altered the model of university education. However, the most salient challenges associated with online learning, how university students are coping with these challenges, and the impact these changes have had on students' communities of learning remain relatively unexplored. Changes to the learning environment have also disrupted existing communities of learning for both lower and upper-year students. Hence, the purpose of our study was to explore how: (1) academic and personal/interpersonal challenges as a result of COVID-19; (2) formal and informal strategies used to cope with these academic and non-academic challenges; (3) and services or resources provided by the institution, if any, affected students' communities of learning. Six focus groups of 5-6 students were conducted, with two focus groups specifically dedicated to upper and lower year students. Questions related to academic and interpersonal challenges, formal and informal coping strategies, and access to/use of university services/resources were posed. Common challenges included poor accommodation from professors and administrators; burnout from little separation school and personal life; lack of support for students transitioning out of university; and difficulties forming and maintaining social networks. These findings suggest the importance of fostering communities of learning informally and formally at universities beyond the pandemic context.

Using mixed-method feasibility studies to examine the impact of a mobile standing desk on undergraduates' sedentary time

OBJECTIVES

To understand experiences with and measure the effect of mobile standing desks (MSD) on undergraduates' sedentary time (ST).

PARTICIPANTS

Two samples of full-time undergraduates in Fall 2018.

METHODS

Study 1 (n = 21): baseline average daily ST was measured via activPAL4^TM inclinometers and the NIGHTLY-WEEK-U questionnaire for 7 days. Participants received a MSD for one week then intervention ST was calculated. Study 2 (n = 28): baseline ST was measured with an online NIGHTLY-WEEK-U questionnaire, participants received a MSD for one month, then intervention ST was calculated. Paired-sample t-tests assessed differences. Interviews/online questions explored experiences.

RESULTS

Study 1: objectively measured (p = .0045, d = .71) and self-report (p = .0005, d = .92) ST reduced significantly post-intervention. Study 2: ST reduced significantly post-intervention (p = < .0001, d = .98). Facilitators and barriers to desk usage were described.

CONCLUSIONS

MSD were effective for reducing undergraduates' ST across one-week and one-month.

Total Sedentary Time and Cognitive Function in Middle-Aged and Older Adults: A Systematic Review and Meta-analysis

Background

An estimated 47 million people have dementia globally, and around 10 million new cases are diagnosed each year. Many lifestyle factors have been linked to cognitive impairment; one emerging modifiable lifestyle factor is sedentary time.

Objective

To conduct a systematic review and meta-analysis of peer-reviewed literature examining the association between total sedentary time with cognitive function in middle-aged and older adults under the moderating conditions of (a) type of sedentary time measurement; (b) the cognitive domain being assessed; (c) looking at sedentary time using categorical variables (i.e., high versus low sedentary time); and (d) the pattern of sedentary time accumulation (e.g., longer versus shorter bouts). We also aimed to examine the prevalence of sedentary time in healthy versus cognitively impaired populations and to explore how experimental studies reducing or breaking up sedentary time affect cognitive function. Lastly, we aimed to conduct a quantitative pooled analysis of all individual studies through meta-analysis procedures to derive conclusions about these relationships.

Methods

Eight electronic databases (EMBASE; Web of Science; PsycINFO; CINAHL; SciELO; SPORTDiscus; PubMed; and Scopus) were searched from inception to February 2021. Our search included terms related to the exposure (i.e., sedentary time), the population (i.e., middle-aged and older adults), and the outcome of interest (i.e., cognitive function). PICOS framework used middle-aged and older adults where there was an intervention or exposure of any sedentary time compared to any or no comparison, where cognitive function and/or cognitive impairment was measured, and all types of quantitative, empirical, observational data published in any year were included that were published in English. Risk of bias was assessed using QualSyst.

Results

Fifty-three studies including 83,137 participants met the inclusion criteria of which 23 studies had appropriate data for inclusion in the main meta-analysis. The overall meta-analysis suggested that total sedentary time has no association with cognitive function (r = −0.012 [95% CI − 0.035, 0.011], p = 0.296) with marked heterogeneity (I² = 89%). Subgroup analyses demonstrated a significant negative association for studies using a device to capture sedentary time r = −0.035 [95% CI − 0.063, − 0.008], p = 0.012). Specifically, the domains of global cognitive function (r = −0.061 [95% CI − 0.100, − 0.022], p = 0.002) and processing speed (r = −0.067, [95% CI − 0.103, − 0.030], p < 0.001). A significant positive association was found for studies using self-report (r = 0.037 [95% CI − 0.019, 0.054], p < 0.001). Specifically, the domain of processing speed showed a significant positive association (r = 0.057 [95% CI 0.045, 0.069], p < 0.001). For prevalence, populations diagnosed with cognitive impairment spent significantly more time sedentary compared to populations with no known cognitive impairments (standard difference in mean = −0.219 [95% CI − 0.310, − 0.128], p < 0.001).

Conclusions

The association of total sedentary time with cognitive function is weak and varies based on measurement of sedentary time and domain being assessed. Future research is needed to better categorize domains of sedentary behaviour with both a validated self-report and device-based measure in order to improve the strength of this relationship. PROSPERO registration number: CRD42018082384.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40798-022-00507-x.

Describing the views of Canadian post-secondary students in health-related disciplines on the recognition of obesity as a chronic disease

OBJECTIVE

This cross-sectional study examined students' perspectives on the ramifications of obesity being recognized as a chronic disease in Canada.

PARTICIPANTS

Undergraduate and graduate students (n = 150) in health-related programs at a major Canadian university.

METHODS

An online survey featured open-ended questions to capture student perspectives on recognizing obesity as a disease. Data were evaluated using content analysis methods.

RESULTS

Positive themes identified included: (a) treatment accessibility; (b) improved healthcare provider attitudes; (c) de-stigmatization of obesity; (d) promotion of health behaviors; and (e) greater research/funding. Negative themes included potential: (a) healthcare system burdens; (b) perpetuation of obesity stigma; (c) medicalization of obesity; and (d) de-emphasis on modifiable risk factors as contributing to obesity.

CONCLUSIONS

There is a need to increase students' understanding of the multifaceted nature of obesity and the prevention of obesity-related stigma within healthcare. Findings may inform post-secondary health curricula and obesity initiatives.

Validity of the occupational sitting and physical activity questionnaire (OSPAQ) for home-based office workers during the COVID-19 global pandemic: A secondary analysis

High levels of occupational sitting is an emerging health concern. As working from home has become a common practice as a result of COVID-19, it is imperative to validate an appropriate self-report measure to assess sitting in this setting. This secondary analysis study aimed to validate the occupational sitting and physical activity questionnaire (OSPAQ) against an activPAL4™ in full-time home-based 'office' workers (n = 148; mean age = 44.90). Participants completed a modified version of the OSPAQ and wore an activPAL4™ for a full work week. The findings suggest that the modified OSPAQ has fair levels of validity in terms of correlation for sitting and standing (ρ = 0.35-0.43, all p < 0.05) and agreement (bias = 2-12%) at the group level; however, estimates were poor at an individual level, as suggested by wide limits of agreement (±22-30%). Overall, the OSPAQ showed to be an easily administered and valid questionnaire to measure group level sitting and standing in this sample of adults.

A combined health action process approach and mHealth intervention to reduce sedentary behaviour in university students - a randomized controlled trial

Objective: This investigation evaluated the effectiveness of a Health Action Process Approach (HAPA) based planning intervention augmented with text messages to reduce student-related sitting time (primary outcome) and increase specific non-sedentary behaviours. Relationships between the HAPA volitional constructs and sedentary and non-sedentary behaviours were also explored. Design: University students (M_age = 21.13 y; SD = 4.81) were randomized into either a HAPA intervention (n = 28) or control (n = 33) condition. Main Outcome Measures: School-related sitting time, time spent in specific non-sedentary behaviours and HAPA volitional constructs were assessed at baseline, weeks 2, 4, 6 (post-intervention) and 8 (follow-up). Results: Significant group by time interaction effects favouring the intervention group were found for sitting time (p = 0.004, ɳ_p² = 0.10), walking time (p = 0.021, ɳ_p² = 0.06) and stretching time (p = 0.023, ɳ_p² = 0.08), as well as for action planning (p < 0.001, ɳ_p² = 0.17), coping planning (p < 0.001, ɳ_p² = 0.20) and action control (p < 0.001, ɳ_p² = 0.20). Significant correlations (p < 0.05) were also found between the HAPA constructs and sitting-related outcomes. Conclusions: Combining a HAPA-based planning intervention with text messages can reduce student-related sitting time in university students.

Supplemental data for this article is available online at https://doi.org/10.1080/08870446.2021.1900574 .

Physical activity and prenatal depression: going beyond statistical significance by assessing the impact of reliable and clinical significant change

BACKGROUND

Previous literature supports exercise as a preventative agent for prenatal depression; however, treatment effects for women at risk for prenatal depression remain unexplored. The purpose of the study was to examine whether exercise can lower depressive symptoms among women who began pregnancy at risk for depression using both a statistical significance and reliable and clinically significant change criteria.

METHODS

This study is a secondary analysis of two randomized controlled trials that followed the same exercise protocol. Pregnant women were allocated to an exercise intervention group (IG) or control group (CG). All participants completed the Center for Epidemiological Depression (CES-D) scale at gestational week 9-16 and 36-38. Women with a baseline score ⩾16 were included. A clinically reliable cut-off was calculated as a 7-point change in scores from pre- to post-intervention.

RESULTS

Thirty-six women in the IG and 25 women in the CG scored ⩾16 on the CES-D at baseline. At week 36-38 the IG had a statistically significant lower CES-D score (14.4 ± 8.6) than the CG (19.4 ± 11.1; p < 0.05). Twenty-two women in the IG (61%) had a clinically reliable decrease in their post-intervention score compared to eight women in the CG (32%; p < 0.05). Among the women who met the reliable change criteria, 18 (81%) in the IG and 7 (88%) in the CG had a score <16 post-intervention, with no difference between groups (p > 0.05).

CONCLUSIONS

A structured exercise program might be a useful treatment option for women at risk for prenatal depression.

Adding team-based financial incentives to the Carrot Rewards physical activity app increases daily step count on a population scale: a 24-week matched case control study

Background

Mobile health applications (mHealth apps) targeting physical inactivity have increased in popularity yet are usually limited by low engagement. This study examined the impact of adding team-based incentives (Step Together Challenges, STCs) to an existing mHealth app (Carrot Rewards) that rewarded individual physical activity achievements.

Methods

A 24-week quasi-experimental study (retrospective matched pairs design) was conducted in three Canadian provinces (pre-intervention: weeks 1–12; intervention: weeks 13–24). Participants who used Carrot Rewards and STCs (experimental group) were matched with those who used Carrot Rewards only (controls) on age, gender, province and baseline mean daily step count (±500 steps/d). Carrot Rewards users earned individual-level incentives (worth $0.04 CAD) each day they reached a personalized daily step goal. With a single partner, STC users could earn team incentives ($0.40 CAD) for collaboratively reaching individual daily step goals 10 times in seven days (e.g., Partner A completes four goals and Partner B completes six goals in a week).

Results

The main analysis included 61,170 users (mean age = 32 yrs.; % female = 64). Controlling for pre-intervention mean daily step count, a significant difference in intervention mean daily step count favoured the experimental group (p < 0.0001; η_p² = 0.024). The estimated marginal mean group difference was 537 steps per day, or 3759 steps per week (about 40 walking min/wk). Linear regression suggested a dose-response relationship between the number of STCs completed (app engagement) and intervention mean daily step count (adjusted R² = 0.699) with each new STC corresponding to approximately 200 more steps per day.

Conclusion

Despite an explosion of physical activity app interest, low engagement leading to small or no effects remains an industry hallmark. In this paper, we found that adding modest team-based incentives to the Carrot Rewards app increased mean daily step count, and importantly, app engagement moderated this effect. Others should consider novel small-teams based approaches to boost engagement and effects.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12966-020-01043-1.

A combined health action process approach and mHealth intervention to reduce workplace sitting time in office-working adults: a secondary analysis examining health-related quality of life and work performance outcomes

OBJECTIVE

This secondary analysis study examined the effects of a 6-week theory-based planning and mHealth text message intervention targeting workplace sitting time on health-related quality of life and work performance in office workers.

DESIGN

Office-working adults (M_age=45.18 ± 11.33 years) were randomised into either a planning + text message intervention (n = 29) or control (n = 31) condition.

OUTCOME MEASURES

Workplace sitting time, time spent in specific non-sedentary behaviours (e.g. standing), health-related outcomes (i.e. emotional well-being, energy/fatigue, perceived role limitations), and work performance were assessed at baseline and week 6.

RESULTS

Significant group by time interaction effects, that favoured the intervention group, were found for perceived role limitations due to emotional health problems and emotional well-being. No significant interaction effects emerged for energy/fatigue, role limitations due to physical health problems or work performance. Significant correlations in the expected direction were found between sedentary/non-sedentary behaviours and health-related outcomes. No significant mediation effects were found to suggest the intervention affected health-related outcomes through reductions in sedentary behaviour.

CONCLUSION

Reducing workplace sitting improves emotional well-being and contributes to fewer perceived role limitations due to emotional health problems among office workers.

Improving remote lifestyle intervention studies in children: Participant and caregiver feedback of the smart heart study

OBJECTIVES

We sought to describe and analyze the quantitative and qualitative feedback obtained from participants and their caregivers of the Smart Heart study, a successful 12-month lifestyle intervention for children with overweight or obesity and congenital heart disease that provided remote lifestyle counseling, to improve future lifestyle interventions in children.

METHODS

Thirty-six participants and caregivers were polled using a standard program evaluation questionnaire at the end of the intervention. Feedback was compiled into themes, and facilitators and barriers to program success were identified.

RESULTS

There was a high level of satisfaction with the intervention and staff interactions as well as a low perceived burden of participation. There were also specific concerns, including mixed impressions regarding technology usage and a less impressive indication of actual impactful behavior change.

CONCLUSIONS

The study identified five themes, and corresponding facilitators and barriers to participant compliance, from the Smart Heart intervention feedback and offered suggestions for improving future lifestyle behavioral intervention study designs in children.

PRACTICE IMPLICATIONS

Remote smartphone counseling is effective and efficient. It is recommended that the counseling messages are specific, the counseling schedule is patient-centric, patient burden is limited, methods with immediate patient feedback are used and family is included when feasible.

Effects of Caffeine and Acute Aerobic Exercise on Working Memory and Caffeine Withdrawal

Studies show that a single bout of exercise confers cognitive benefits. However, many individuals use psychoactive substances such as caffeine to enhance cognitive performance. The effects of acute exercise in comparison to caffeine on cognition remain unknown. Furthermore, caffeine use is associated with withdrawal symptoms upon cessation. Whether acute exercise can reduce withdrawal symptoms also remains unknown. The objectives of this study were to compare the effects of acute moderate intensity aerobic exercise to caffeine on working memory (WM) and caffeine withdrawal symptoms (CWS). In Phase I, non-caffeine (n = 29) and caffeine consumers (n = 30) completed a WM assessment, followed by acute exercise and caffeine. In Phase II, caffeine consumers (n = 25) from Phase I underwent the WM assessment and reported CWS following a 12-hour deprivation period. Acute moderate intensity aerobic exercise and caffeine (1.2 mg/kg) significantly improved WM accuracy and reduced CWS comparably. WM performance was not reduced following caffeine deprivation.

Smoking zones versus smoke-free zones on Canadian postsecondary campuses: Which zone is more effective, adhered to and preferred?

INTRODUCTION

This study aims to determine if smokers at post-secondary campuses are more likely to adhere to smoke-free zones (areas where smoking is not permitted) or smoking zones (areas where smoking is permitted) based on preference and effectiveness.

METHODS

A self-reported survey was developed and administered at two postsecondary institutions; Western University (smoke-free zones) and Fanshawe College (smoking zones). Smokers were asked how often they use these zones, which zone is preferred and which zone they think is more effective. A chi-squared analysis was performed to determine if there were differences in the frequency of responses.

RESULTS

A total of 239 surveys were collected, 119 from Western and 120 from Fanshawe. Of these, 87% of respondents at Fanshawe were aware of where they could smoke on campus, and 67% reported that they mostly or always used these spaces. At Western, significantly fewer respondents knew where to smoke (57%), and only 30% reported mostly or always using appropriate zones (p<0.05). More participants at Fanshawe indicated that they had been told by someone in authority where they could smoke (36%) compared to Western (19%, p<0.05). At Fanshawe, 63% of respondents stated that smoking zones mostly or always effectively indicated where it was appropriate to smoke on campus compared to only 18% at Western (p<0.05). Both groups indicated they preferred the zone they currently had. Finally, more participants from Fanshawe intend to quit smoking within 6 months (61% from Fanshawe vs 49% from Western, p<0.05).

CONCLUSIONS

Smoking zones on post-secondary campuses may be more effective and adhered to by smokers than smoke-free zones.

The effects of sedentary behaviour interventions on work-related productivity and performance outcomes in real and simulated office work: A systematic review

This review examined the impact of environmental, behavioral, and combined interventions to reduce occupational sedentary behaviour on work performance and productivity outcomes. Productivity outcomes were defined as variables assessing work-related tasks (e.g., typing, mouse), whereas performance outcomes were categorized as any variables assessing cognition that did not mimic work-related tasks. Nine databases were searched for articles published up to January 2018. Sixty-three studies were identified that met the inclusion criteria: 45 examined a productivity outcome (i.e., typing, mouse, work-related tasks, and absenteeism), 38 examined a performance outcome (i.e., memory, reading comprehension, mathematics, executive function, creativity, psychomotor function, and psychobiological factors), and 30 examined a self-reported productivity/performance outcome (i.e., presenteeism or other self-reported outcome). Overall, standing interventions do not appear to impact productivity/performance outcomes, whereas walking and cycling interventions demonstrate mixed null/negative associations for productivity outcomes. Hence, standing interventions to reduce occupational sedentary behaviour could be implemented without negatively impacting productivity/performance outcomes.

Structured diet and exercise guidance in pregnancy to improve health in women and their offspring: study protocol for the Be Healthy in Pregnancy (BHIP) randomized controlled trial

BACKGROUND

Evidence from epidemiological and animal studies support the concept of programming fetal, neonatal, and adult health in response to in utero exposures such as maternal obesity and lifestyle variables. Excess gestational weight gain (GWG), maternal physical activity, and sub-optimal and excess nutrition during pregnancy may program the offspring's risk of obesity. Maternal intake of dairy foods rich in high-quality proteins, calcium, and vitamin D may influence later bone health status. Current clinical practice guidelines for managing GWG are not founded on randomized trials and lack specific "active intervention ingredients." The Be Healthy in Pregnancy (BHIP) study is a randomized controlled trial (RCT) designed to test the effectiveness of a novel structured and monitored Nutrition + Exercise intervention in pregnant women of all pre-pregnancy weight categories (except extreme obesity), delivered through prenatal care in community settings (rather than in hospital settings), on the likelihood of women achieving recommended GWG and a benefit to bone status of offspring and mother at birth and six months postpartum.

METHODS

The BHIP study is a two-site RCT that will recruit up to 242 participants aged > 18 years at 12-17 weeks of gestation. After baseline measures, participants are randomized to either a structured and monitored Nutrition + Exercise (intervention) or usual care (control) program for the duration of their pregnancy. The primary outcome of the study is the percent of women who achieve GWG within the Institute of Medicine (IOM) guidelines. The secondary outcomes include: (1) maternal bone status via blood bone biomarkers during pregnancy; (2) infant bone status in cord blood; (3) mother and infant bone status measured by dual-energy absorptiometry scanning (DXA scan) at six months postpartum; (4) other measures including maternal blood pressure, blood glucose and lipid profiles, % body fat, and postpartum weight retention; and (5) infant weight z-scores and fat mass at six months of age.

DISCUSSION

If effective, this RCT will generate high-quality evidence to refine the nutrition guidelines during pregnancy to improve the likelihood of women achieving recommended GWG. It will also demonstrate the importance of early nutrition on bone health in the offspring.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT01689961 Registered on 21 September 2012.

Anthropometric and body composition changes in smokers vs abstainers following an exercise-aided pharmacotherapy smoking cessation trial for women

INTRODUCTION

Post-cessation weight gain contributes to smoking relapse, especially for women. Furthermore, excess weight in the form of android or visceral fat is associated with metabolic health problems. For this study, a secondary analysis was conducted in 2015 to determine whether quitting status, achieved through a 14 week supervised exercise-aided nicotine replacement therapy (NRT) cessation program [Getting Physical on Cigarette Trial-2009 to 2013; Prapavessis, et al., 2016], affects anthropometric and body composition parameters in female smokers (N = 413, M age = 42.39 years).

METHODS

Anthropometric (weight and BMI) and body composition (% total body fat, % android fat, lean mass and visceral fat) indices were assessed at baseline and end of treatment. Smoking status was confirmed weekly from expired breath carbon monoxide. Adherence to exercise and NRT patch was calculated from the number of exercise sessions attended and patches worn to the number of exercise sessions offered and patches supplied, respectively.

RESULTS

Factorial (smoking status) ANCOVAs controlling for baseline anthropometric and body composition parameters as well as adherence to exercise and NRT revealed significant differences in weight (p = .033; ɳ_p² = 0.017) and BMI (p = .020; ɳ_p² = 0.020) at week 14. This equated to abstainers weighing 1.26 kg more and having a 0.52 higher BMI than smokers. No significant differences were found for any of the body composition parameters at week 14 (ɳ_p² range from 0.001-0.007).

CONCLUSIONS

Abstainers gain modest weight compared to smokers. This weight gain is related to increases in lean mass and not total, android, or visceral fat.

Informing population-specific smoking policy development for college campuses: An observational study

INTRODUCTION

In Canada, young adults have the highest smoking rates among all other population groups and specifically college students are at a higher risk. To implement effective policies that can prevent smoking and increase cessation, a population-specific approach is recommended.

METHODS

Smoking and non-smoking young adults enrolled in a college program were recruited. Participants who did not smoke were asked to complete questionnaires about their demographics, college experience and the college environment. Additionally, they completed The Perceived Stress Scale and The Center for Epidemiologic Studies - Depression Scale. Students who were current smokers completed the same questionnaires with the addition of one questionnaire about their smoking behaviors. Percentages, means and standard deviations were used to describe the variables of interest and a chi-squared analysis was performed, when possible, to test the difference in response frequency between smoking and non-smoking participants.

RESULTS

Differences were observed between smoking (n=65) and non-smoking students (n=214). Specifically, smokers were more likely to have a family member that smoked and to participate in binge drinking. Both groups indicated that they are unaware of campus smoking regulations; however smokers were more opposed to implementing smoke-free policies.

CONCLUSIONS

College students are unaware of campus smoking regulations. The descriptive information and differences observed between smoking and non-smoking students in this study should be taken into consideration when developing future smoking regulations/policies on college campuses.

Affect and cortisol mechanisms through which acute exercise attenuates cigarette cravings during a temporary quit attempt

INTRODUCTION

A number of mechanisms have been proposed to explain how exercise attenuates cravings among temporarily abstinent smokers; however, research has presented mixed findings. The aim of this study was to further investigate the mechanistic role of positive and negative affect and cortisol in the exercise-craving reduction relationship.

METHODS

Adult smokers (N=110, male=56, M age=33.1, M cigarettes/day=15.4) provided baseline affective and cortisol data (T1). After an 18-h period of abstinence, participants were randomized to a passive sitting (PSG) or moderate exercise group (MEG; 40-68% of heart rate reserve) for 10min. Affect and cortisol data were also collected immediately before (T2) and after (T3) the condition.

RESULTS

The smoking abstinence manipulation increased cravings (p<0.001, eta=0.40) and negative affect (p<0.001, eta=0.17), as well as decreased positive affect (p<0.001, eta=0.08) and cortisol (trending, p=0.07, η2=0.04). As expected, a significant reduction in cravings from T2 to T3 was found for MEG but not PSG (p<0.001, eta=0.25). Mediation was tested using Sobel and bootstrapping tests with residual change scores of mediators and cravings. Findings showed that both positive and negative affect, but not cortisol, mediated the relationship between exercise and cravings.

CONCLUSIONS

Understanding the mechanisms by which exercise induces craving reductions will better allow researchers and healthcare professionals to infer causality and implement interventions guided by the processes that yield such desirable outcomes.

Remote Lifestyle Counseling Influences Cardiovascular Health Outcomes in Youth with Overweight or Obesity and Congenital Heart Disease

BACKGROUND

Children with overweight/obesity and congenital heart disease (CHD) are at increased cardiovascular risk. A lifestyle intervention may help reduce these risks. We sought to determine the feasibility of a smartphone-based lifestyle intervention to improve cardiovascular health outcomes in children with overweight/obesity and CHD.

METHODS

We examined the effect of bi-weekly nutrition and fitness counseling delivered via smartphone over 12 months. Thirty-four youth, previously diagnosed with CHD and with overweight or obesity, participated in the intervention. They were divided into two groups depending on whether the heart disease required surgical correction (operated, n = 19) or not (non-operated, n = 15). Anthropometry, body composition cardiorespiratory exercise capacity, and cardio-metabolic risk factors were assessed at baseline, 6 months, and 12 months.

RESULTS

Statistically significant decreases in waist circumference (WC), body mass index z-score, WC z-score, and waist to height ratio z-score were observed at 6 and 12 months in the operated group. A significant linear increase in lean body mass was observed in both groups. The study also had a high retention rate and a low attrition rate.

CONCLUSION

The observed changes in anthropometry were positive with significant improvement to some cardiovascular and metabolic risk indicators. However, this was only observed in the operated group suggesting that other factors, such as perception of condition and self-efficacy, may influence lifestyle behaviors. The results from this pilot study clearly demonstrate the feasibility to perform a larger controlled study on remote lifestyle intervention in children with congenital heart defects and overweight or obesity.

The use of smartphones to influence lifestyle changes in overweight and obese youth with congenital heart disease: a single-arm study: Pilot and feasibility study protocol: Smart Heart Trial

Background

Both obesity and congenital heart disease (CHD) are risk factors for the long-term cardiovascular health of children and adolescents. The addition of smart mobile technology to conventional lifestyle counseling for weight management offers great potential to appeal to technologically literate youth and can address a large geographical area with minimal burden to participants. This pilot study seeks to examine the influence of a 1-year lifestyle intervention on nutrition and physical activity-related health outcomes in overweight or obese children and adolescents with CHD.

Methods

This is a pilot and feasibility study which utilizes a single-arm, prospective design with a goal to recruit 40 overweight and obese patients. The feasibility metrics will evaluate the integrity of the study protocol, data collection and questionnaires, recruitment and consent, and acceptability of the intervention protocol and primary outcome measures. The primary clinical outcome metrics are anthropometry, body composition, and cardiorespiratory exercise capacity. The secondary clinical metrics include quality of life, nutrition and physical activity behavior, lung and muscle function, and cardio-metabolic risk factors. Outcomes are assessed at baseline, 6 months, and 1 year. To date, a total of 36 children and youth (11 girls), aged 7–17 years (mean = 14.4 years), have commenced the intervention. Recruitment for the study was initiated in June 2012 and is currently ongoing.

Discussion

The information provided in this paper is intended to help researchers and health professionals with the development and evaluation of similar lifestyle intervention programs. Since the application of smartphones to pediatric cardiac health and obesity management is a novel approach, and continued research in this area is warranted, this paper may serve as a foundation for further exploration of this health frontier and inform the development of a broader strategy for obesity management in pediatric cardiology.

Trial registration

This pilot study was retrospectively registered at the www.ClinicalTrials.gov registry as NCT02980393 in November 2016, with the study commencing in May 2012. Study protocol version 15OCT2014.

Electronic supplementary material

The online version of this article (10.1186/s40814-017-0207-y) contains supplementary material, which is available to authorized users.

Measuring Adherence to a Nutrition and Exercise Lifestyle Intervention: Is Program Adherence Related to Excessive Gestational Weight Gain?

To identify adherence required to achieve target health outcome(s) in nutrition and/or exercise interventions, a measurement tool that tracks objective and self-reported measures of adherence is necessary. The purpose of this study was to design an adherence measurement tool and test it retrospectively on the Nutrition and Exercise Lifestyle Intervention Program (NELIP; Ruchat et al., Medicine and Science in Sports and Exercise, 44(8), 1419-1426, 2012; Mottola et al., Medicine and Science in Sports and Exercise, 42(2), 265-272, 2010), designed to prevent excessive gestational weight gain (EGWG). The tool was based on the goals of the NELIP and included a grading system for each behavior (exercise and nutrition). It was used to determine whether adherence scores could differentiate excessive versus acceptable weight gain during pregnancy across pre-pregnancy body mass index (BMI) categories. Results showed irrespective of pre-pregnancy BMI, women with acceptable weight gain had significantly higher adherence (p < 0.05) than women with excessive weight gain. It is recommended that this adherence tool be included in future prospective lifestyle intervention studies.

Economic evaluation of an exercise-counselling intervention to enhance smoking cessation outcomes: The Fit2Quit trial

Background

In the Fit2Quit randomised controlled trial, insufficiently-active adult cigarette smokers who contacted Quitline for support to quit smoking were randomised to usual Quitline support or to also receive ≤10 face-to-face and telephone exercise-support sessions delivered by trained exercise facilitators over the 24-week trial. This paper aims to determine the cost-effectiveness of an exercise-counselling intervention added to Quitline compared to Quitline alone in the Fit2Quit trial.

Methods

Within-trial and lifetime cost-effectiveness were assessed. A published Markov model was adapted, with smokers facing increased risks of lung cancer and cardiovascular disease.

Results

Over 24 weeks, the incremental programme cost per participant in the intervention was NZ$428 (US$289 or €226; purchasing power parity-adjusted [PPP]). The incremental cost-effectiveness ratio (ICER) for seven-day point prevalence measured at 24-week follow-up was NZ$31,733 (US$21,432 or €16,737 PPP-adjusted) per smoker abstaining. However, for the 52% who adhered to the intervention (≥7 contacts), the ICER for point prevalence was NZ$3,991 (US$2,695 or €2,105 PPP-adjusted). In this adherent subgroup, the Markov model estimated 0.057 and 0.068 discounted quality-adjusted life-year gains over the lifetime of 40-year-old males (ICER: NZ$4,431; US$2,993 or €2,337 PPP-adjusted) and females (ICER: NZ$2,909; US$1,965 or €1,534 PPP-adjusted).

Conclusions

The exercise-counselling intervention will only be cost-effective if adherence is a minimum of ≥7 intervention calls, which in turn leads to a sufficient number of quitters for health gains.

Trial registration

Australasian Clinical Trials Registry Number ACTRN12609000637246

Implementation of clinical research trials using web-based and mobile devices: challenges and solutions

BACKGROUND

With the increasing implementation of web-based, mobile health interventions in clinical trials, it is crucial for researchers to address the security and privacy concerns of patient information according to high ethical standards. The full process of meeting these standards is often made more complicated due to the use of internet-based technology and smartphones for treatment, telecommunication, and data collection; however, this process is not well-documented in the literature.

RESULTS

The Smart Heart Trial is a single-arm feasibility study that is currently assessing the effects of a web-based, mobile lifestyle intervention for overweight and obese children and youth with congenital heart disease in Southwestern Ontario. Participants receive telephone counseling regarding nutrition and fitness; and complete goal-setting activities on a web-based application. This paper provides a detailed overview of the challenges the study faced in meeting the high standards of our Research Ethics Board, specifically regarding patient privacy.

CONCLUSION

We outline our solutions, successes, limitations, and lessons learned to inform future similar studies; and model much needed transparency in ensuring high quality security and protection of patient privacy when using web-based and mobile devices for telecommunication and data collection in clinical research.

Feasibility of an exercise intervention for fatigued breast cancer patients at a community-based cardiac rehabilitation program

Purpose

Exercise is beneficial to quality of life after cancer treatment, yet few cancer survivors meet exercise guidelines. Our study sought to determine the feasibility of an oncology rehabilitation exercise program embedded within a cardiac rehabilitation program.

Methods

Patients who rated their fatigue >4/10 after completion of adjuvant chemotherapy for breast cancer were screened for eligibility and the outcomes were assessed (Piper Fatigue Scale, Functional Assessment of Cancer Therapy-Breast [FACT-B], Edmonton Symptom Assessment System, body composition, stress test, and physical activity measurement [accelerometer]). Participants received individualized exercise prescription. Following the 16-week program, repeat assessment plus patient acceptance and satisfaction survey was completed. The primary end point was the composite of accrual rate >25%, program adherence >80%, and mean compliance with accelerometer use >80%.

Results

Twenty of 24 screened patients consented to the study and completed the baseline assessment. Adherence was 30.3%. Mean accelerometer use was 3.88/7 days (78%). Fatigue at baseline was rated at 4.82/10, and at 3.59 (p = 0.09) after the intervention. Overall well-being (FACT-B) score changed from 92.7 to 98.3 (p = 0.05). There were no significant changes in body composition (except for bone mineral content), aerobic exercise capacity, or activity patterns.

Conclusion

Although the primary outcome was not met, our study indicates that an oncology exercise rehabilitation program can be incorporated into an existing cardiac rehabilitation program. Based on feedback received, we propose that in order to achieve exercise goals, frequent, encouraging, and tailored feedback and group sessions to foster a sense of community may additionally be needed to strengthen adherence to a prescribed exercise program.

Cognitive and Motivational Factors Associated with Sedentary Behavior: A Systematic Review

Excessive time spent in sedentary behavior (SB) is associated with numerous health risks. These associations remain even after controlling for moderate-to-vigorous physical activity (PA) and body mass index, indicating that efforts to promote leisure time physical activity alone are insufficient. Cognitive and motivation variables represent potentially modifiable factors and have the potential of furthering our understanding of sedentary behavior. Hence, a systematic review was conducted to synthesize and critique the literature on the relationship between cognitive and motivational factors and sedentary behaviors. In April 2016, four electronic databases (Psych info, Pub Med, SPORTDiscus, Web of Science) were searched and a total of 4866 titles and abstracts were reviewed. After meeting inclusion criteria, study characteristics were extracted and the methodological quality of each study was assessed according to the Downs and Black Checklist. PRISMA guidelines for reporting of systematic reviews were followed. Twenty-five studies (16 cross-sectional, 8 longitudinal and one examining two populations and employing both a cross-sectional and prospective design) assessed 23 different cognitive and motivational factors. Seventeen studies were theory-based and 8 did not employ a theoretical model. Results showed that among SB-related cognitions, risk factors for greater sedentary time included having a more positive attitude towards SB, perceiving greater social support/norms for SB, reporting greater SB habits, having greater intentions to be sedentary, and having higher intrinsic, introjected, and external motivation towards SB. Protective factors associated with lower sedentary time included having greater feelings of self-efficacy/control over SB and greater intentions to reduce SB. Among PA-related cognitions, protective factors for lower SB included a more positive attitude towards PA, having greater social support/norms for PA, greater self-efficacy/control for PA, higher PA intentions, and higher intrinsic and identified motivation towards PA. In addition, feeling more supported and empowered in general was related with lower levels of SB. The average methodological quality score for included studies was 69% (SD = 9.15%; range 35–80%). In conclusion, a number of cognitive and motivational factors were identified that were associated with sedentarism. These findings have come from reasonably high quality studies. To further extend our understanding of the relation between cognitive and motivational factors and SB, more longitudinal, theory-driven studies examining cognitions and motivation from a sedentary perspective are required.

Using Consensus as a Criterion for Groupness

The purpose of the study was to examine how the exclusion of teams failing to meet varying statistical criteria for consensus on cohesiveness influences the magnitude of the cohesion– team success relationship. The index of agreement was calculated for 78 teams (N = 1,000 athletes) that had completed the Group Environment Questionnaire. Results showed that excluding teams because they fail to satisfy various criteria for consensus leads to changes in the magnitude of the cohesion–team success relationship. The magnitude of the relationship between team success and the individual attractions to group-task manifestation of cohesion showed progressive decreases as criteria required to demonstrate consensus became more stringent. Conversely, the magnitude of the relationship between team success and the group integration–task and group integration–social manifestations of cohesion showed progressive increases as criteria required to demonstrate consensus became more stringent. The results are discussed in terms of their relationship to group dynamics theory and practice.

Increasing Nonsedentary Behaviors in University Students Using Text Messages: Randomized Controlled Trial

BACKGROUND

Sedentary behavior (SB) has been linked to many health problems such as type 2 diabetes and heart disease. Increasing the length and frequency of breaks from sitting and increasing the time spent standing and engaged in light and moderate physical activity are ways to decrease SB. Text message-based interventions have succeeded in aiding smoking cessation and increase both physical activity and healthy eating, but they have not been shown to reduce SB.

OBJECTIVE

The primary purpose of this pilot study was to determine the effectiveness of a text message-based intervention in increasing nonsedentary behaviors in university students. A secondary purpose was to (1) determine whether the intervention could enhance self-efficacy beliefs for decreasing SB and (2) whether these efficacious beliefs could predict actual SB.

METHODS

Eighty-two university students were recruited via mass emails and randomized into intervention (SB-related text messages) or control (text messages unrelated to SB) groups. Participants received daily text messages scheduled by the researcher encouraging breaks from sitting, standing, light- and moderate-intensity physical activity (PA). They then reported various SBs via Web-based questionnaires at four time points (baseline, 2, 4, and 6 weeks). Self-efficacious beliefs toward taking breaks from sitting and decreasing the amount of time spent sitting were assessed at the same time points.

RESULTS

Last observation carried forward (LOCF) method was used for incomplete data as an intent-to-treat (ITT) analysis (intervention group n=15, control group n=11). Small-to-moderate effects favoring the text intervention group were found at 6 weeks for break frequency -14.64 minutes, break length +.59 minutes, standing +24.30 min/day, light-intensity +74.34 min/day, and moderate-intensity + 9.97 min/day PA. Only light-intensity PA approached significance (P=.07). Self-efficacy beliefs also favored the text intervention group and reached significance (P=.032) for sitting less. Significant (P<.05) relations were found between the self-efficacy constructs and breaks, standing, and light or moderate PA.

CONCLUSIONS

Text messages have the potential to increase nonsedentary behaviors in university students. These messages can increase self-efficacy beliefs to take more breaks and reduce sitting time. Efficacious beliefs can predict actual SB and to a lesser extent light- and moderate-intensity PA.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02562937; https://clinicaltrials.gov/ct2/show/NCT02562937 (Archived by WebCite at http://www.webcitation.org/6jVLwXE5M).

Cohesion and Work Output

The purpose of this investigation was to examine the relationship between group cohesion and individual work output (effort) in sport teams. Results showed that athletes who scored high on the Individual Attractions to the Group Task (AGT-T) Scale from the Group Environment Questionnaire (GEQ) worked harder (predicted from a bag of expired air at the end of training and expressed as apercentage relative to the maximal volume of oxygen consumption) than athletes who scored low on the ATG-T The results extend previous research that has shown that cohesion is positively associated with individual adherence in sport teams and exercise classes. Recommendations forfuture research are discussed.