A Preliminary Investigation into the Effect of Continuous Vigorous Exercise and Lifestyle-embedded Physical Activity upon Acute Glycaemic Regulation

Background and Purpose Continuous glucose monitoring (CGM) has recently emerged as a new tool for patients with diabetes mellitus to monitor glucose levels and aid maintainenance of euglycaemia. CGM provides information on ambulatory, postprandial and nocturnal glucose excursions. Extant research has thus far focused upon charting glucose excursions in diabetic patients, with limited normoglycaemic comparative data available. Additionally little is known upon how physical activity affects acute blood glucose regulation. The purpose of this study was to investigate the effect of continuous exercise and lifestyle-embedded physical activity upon glucose regulation, and assess the feasibility of prolonged CGM data collection in a normoglycaemic individual. Method One physically active non-diabetic male [age: 22 y; mass: 71.5 kg; height: 181 cm] underwent 7 days CGM, performing 3 trial conditions: a sedentary control (< 2500 steps, pedometer controlled), a continuous exercise condition (2 x 30 min treadmill running at 70% HRmax), and a lifestyle-embedded physical activity condition (100 min fractionalized moderate activity). Diet was standardised and physical activity levels were monitored via accelerometry throughout. Results Descriptive results displayed lower whole day mean blood glucose levels in both the continuous (Mean ± SD: 5.2 ± 0.3 mmol.L-1) and lifestyle conditions (5.3 ± 1.1 mmol.L-1), compared to sedentary control (5.6 ± 0.5 mmol.L-1). A post exercise decrease in glucose levels (2 h pre-6 h post (5.3 – 5.1 mmol.L-1)) with a carryover effect for the following day (reduced mean glucose 24 h pre-post (5.5 ± 0.5 - 5.2 ± 0.3 mmol.L-1)) was identified in the continuous exercise condition. In addition a significant correlation (R= 0.75, P = 0.02) was found between physical activity counts and CGM glucose values (mmol.L-1) during the continuous bout of vigorous exercise. Discussion and Conclusions It was concluded that day to day glucose homeostasis may be optimised through bouts of continuous vigorous exercise. The utilisation of CGM in exercise protocols and prolonged data collection is deemed a feasible proposition; however larger scale studies may pose logistical problems. This study was limited by its single subject design and specificity to normoglycaemic populations, future studies should look to include a greater sample size and characterise glycaemic regulation in pre-diabetic and diabetic populations

Teacher perceptions on the delivery and implementation of movement integration strategies: the CLASS PAL (Physically Active Learning) Programme

Children sit for extended periods in the school classroom. Movement integration (MI) methods (e.g. active breaks, physically active lessons) could be used to break/reduce sitting time and improve classroom behaviour and engagement. Limited evidence is available on teacher perceptions of what influences the implementation of MI. Interviewed primary school teachers reported factors perceived to influence implementation at a variety of levels including individual (e.g. teacher and pupil characteristics, time, behavioural management) and school (e.g. whole school approach; and external to school expectations). In addition suggestions for increasing adoption and implementation of MI (e.g. communicating MI initiatives to schools) were identified

Tackling the lack of diversity in health research

Peer reviewedPostprin

A feasibility study of ‘The StepSmart Challenge’ to promote physical activity in adolescents

Funder: Research Trainees Coordinating Centre; doi: http://dx.doi.org/10.13039/501100000659Abstract: Background: Inactive lifestyles are becoming the norm and creative approaches to encourage adolescents to be more physically active are needed. Little is known about how gamification techniques can be used in physical activity interventions for young people. Such approaches may stimulate interest and encourage physical activity behaviour. The study investigated the feasibility of implementing and evaluating a physical activity intervention for adolescents which included gamification techniques within schools. We tested recruitment and retention strategies for schools and participants, the use of proposed outcome measures, and explored intervention acceptability. Methods: This school-based feasibility study of a randomised cluster trial recruited adolescents aged 12–14 years (n = 224) from five schools (three intervention; two control) in Belfast, Northern Ireland. The 22-week intervention (The StepSmart Challenge) informed by self-determination theory and incorporating gamification strategies involved a school-based pedometer competition. Outcomes, measured at baseline, and post-intervention (at 22 weeks post-baseline and 52 weeks post-baseline) included daily minutes of moderate to vigorous physical activity (MVPA) (measured using ActiGraph accelerometer), mental wellbeing (Warwick-Edinburgh Mental Wellbeing Scale), social support for physical activity, time preference (for delayed and larger rewards or immediate and smaller rewards), pro-social behaviour (Strengths and Difficulties Questionnaire (SDQ)) and the influence of social networks. The intervention’s acceptability was explored in focus groups. Results: We invited 14 schools to participate; eight showed interest in participating. We recruited the first five who responded; all five completed the trial. Of the 236 pupils invited, 224 participated (94.9%): 84.8% (190/224) provided valid MVPA (minutes/day) at baseline and 57.2% (123/215) at 52 weeks. All other outcomes were well completed apart from the SDQ (65% at baseline). Qualitative data highlighted that participants and teachers found The StepSmart Challenge to be an acceptable intervention. Conclusions: The level of interest and high recruitment and retention rates provide support for the feasibility of this trial. The intervention, incorporating gamification strategies and the recruitment methods, using parental opt-out procedures, were acceptable to participants and teachers. Teachers also suggested that the implementation of The StepSmart Challenge could be embedded in a lifelong learning approach to health within the school curriculum. As young people’s lives become more intertwined with technology, the use of innovative gamified interventions could be one approach to engage and motivate health behavioural change in this population. Trial registration: NCT02455986 (date of registration: 28 May 2015)

Accelerometer data requirements for reliable estimation of habitual physical activity and sedentary time of children during the early years - a worked example following a stepped approach.

This study presents a worked example of a stepped process to reliably estimate the habitual physical activity and sedentary time of a sample of young children. A total of 299 children (2.9 ± 0.6 years) were recruited. Outcome variables were daily minutes of total physical activity, sedentary time, moderate to vigorous physical activity and proportional values of each variable. In total, 282 (94%) provided 3 h of accelerometer data on ≥1 day and were included in a 6-step process: Step-1: determine minimum wear-time; Step-2: process 7-day-data; Step-3: determine the inclusion of a weekend day; Step-4: examine day-to-day variability; Step-5: calculate single day intraclass correlation (ICC) (2,1); Step-6: calculate number of days required to reach reliability. Following the process the results were, Step-1: 6 h was estimated as minimum wear-time of a standard day. Step-2: 98 (32%) children had ≥6 h wear on 7 days. Step-3: no differences were found between weekdays and weekend days (P ≥ 0.05). Step-4: no differences were found between day-to-day variability (P ≥ 0.05). Step-5: single day ICC’s (2,1) ranged from 0.48 (total physical activity and sedentary time) to 0.53 (proportion of moderate to vigorous physical activity). Step-6: to reach reliability (ICC = 0.7), 3 days were required for all outcomes. In conclusion following a 7 day wear protocol, ≥6 h on any 3 days was found to have acceptable reliability. The stepped-process offers researchers a method to derive sample-specific wear-time criterion