Browsing by Author "Brink, Nicholas"

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    Impacts of heat exposure in utero on longterm health and social outcomes: a systematic review
    (BioMed Central (BMC), 2024) Norris, Shane; Brink, Nicholas; Lakhoo, Darshnika P.; Solarin, Ijeoma; Maimela, Gloria; von Dadelszen, Peter; Chersich, Matthew F.
    Background: Climate change, particularly global warming, is amongst the greatest threats to human health. While short-term effects of heat exposure in pregnancy, such as preterm birth, are well documented, long-term effects have received less attention. This review aims to systematically assess evidence on the long-term impacts on the foetus of heat exposure in utero. Methods: A search was conducted in August 2019 and updated in April 2023 in MEDLINE(PubMed). We included studies on the relationship of environmental heat exposure during pregnancy and any long-term outcomes. Risk of bias was assessed using tools developed by the Joanna-Briggs Institute, and the evidence was appraised using the GRADE approach. Synthesis without Meta-Analysis (SWiM) guidelines were used. Results: Eighteen thousand six hundred twenty one records were screened, with 29 studies included across six outcome groups. Studies were mostly conducted in high-income countries (n=16/25), in cooler climates. All studies were observational, with 17 cohort, 5 case-control and 8 cross-sectional studies. The timeline of the data is from 1913 to 2019, and individuals ranged in age from neonates to adults, and the elderly. Increasing heat exposure during pregnancy was associated with decreased earnings and lower educational attainment (n=4/6), as well as worsened cardiovascular (n=3/6), respiratory (n=3/3), psychiatric (n=7/12) and anthropometric (n=2/2) outcomes, possibly culminating in increased overall mortality (n=2/3). The effect on female infants was greater than on males in 8 of 9 studies differentiating by sex. The quality of evidence was low in respiratory and longevity outcome groups to very low in all others. Conclusions Increasing heat exposure was associated with a multitude of detrimental outcomes across diverse body systems. The biological pathways involved are yet to be elucidated, but could include epigenetic and developmental perturbations, through interactions with the placenta and inflammation. This highlights the need for further research into the long-term effects of heat exposure, biological pathways, and possible adaptation strategies in studies, particularly in neglected regions. Heat exposure in-utero has the potential to compound existing health and social inequalities. Poor study design of the included studies constrains the conclusions of this review, with heterogenous exposure measures and outcomes rendering comparisons across contexts/studies difficult.
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    The ‘real world’ application of postactivation potentiation in a physical training and competition environment.
    (2022) Brink, Nicholas
    Postactivation potentiation is a physiological concept that implies that a conditioning activity can enhance the outcome of a subsequent task. These tasks are normally power related activities like maximal sprinting or jumping. This study explored whether postactivation potentiation could be achieved in healthy adults using a bodyweight conditioning activity. Three original studies were conducted as part of this thesis. The researchers conducted study one and two to investigated whether a maximal intensity body-weight task could induce postactivation potentiation in a similar subsequent task. A randomised controlled trial was conducted in each case. The researchers used study three to investigated whether a body weight conditioning activity could improve the outcome of a subsequent task. A systematic review and metaanalysis were conducted which included the results of study one and two. Study one demonstrated that relative to the baseline there was a significant improvement in the maximal linear sprint group over 10 m and 20 m at two minutes of 0.12 m.s-1 and 0.11 m.s-1 and at six minutes of 0.11m.s-1 and 0.12m.s-1 respectively. There was also a significant improvement in the control group between two and six minutes post-intervention at 10 m and 20 m of 0.06 m.s1 and 0.08 m.s-1 respectively. There was no significant difference between the intervention and control group. Based upon this finding a maximal sprint acceleration may enhance the outcome of a subsequent maximal sprint acceleration. The researchers demonstrated in study two that relative to the baseline there was a significant improvement in the maximal vertical jump group in jump height (1.89 cm) and power output (114.45 W) at two minutes. There was no change in control group across the experiment and no significant difference between the control group and the intervention group. These findings suggests that two maximal vertical jumps may enhance the outcome of a subsequent maximal vertical jump after two minutes. However, these enhancements were not sustained for a further four minutes. Study three demonstrated that there was a small overall effect of 0.30 (95% CI 0.14 to 0.46, p = 0.0003) in favour of using a bodyweight conditioning activity to improve the outcome of a subsequent vertical jump or linear sprint. The interpretation of these outcomes indicates that while the enhancement may be small to moderate in effect, they are in favour of using bodyweight conditioning activities to enhance the outcomes of a maximal vertical jump or maximal sprint. Vertical jump and sprint ability are highly associated with performance outcomes in many sports. Bodyweight conditioning activities allows for a simple, yet effective approach with minimal adverse consequences to achieve postactivation potentiation and an enhanced state of performance prior to participation in a ‘real world’ environment