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Operators of heavy equipment are often exposed to high levels of whole-body vibration (WBV), which has been associated with a variety of adverse health outcomes. Although anthropometric factors are known to impact vibration dose and risk of low back pain, studies have yet to investigate the influence of anthropometric factors on muscle activation during WBV exposure. This study quantified the relationships between muscle activation, vibration frequency, body mass, body mass index (BMI), and height both pre- and post-fatigue. Muscle activation of the external oblique (EO), internal oblique (IO), lumbar erector spinae (LE) and thoracic erector spinae (TE) were quantified using surface electromyography. Results indicate increased activation with increased mass, BMI, and frequency for the LE, TE, and IO, which may be a result of increased activation to stabilize the spine. Decreased muscle activation with increased height was seen in the TE, IO, and pre-fatigue EO, which could indicate higher risk for low back injury since height is associated with increased forces on the spine. This may contribute to the association between increased low back pain incidence and increased height. Results suggest that ISO 2631-1 health guidance should incorporate anthropometric factors, as these may influence muscle activation and back injury risk.

BackgroundAdults' views and behaviors toward children can vary from being supportive to shockingly abusive, and there are significant unanswered questions about the psychological factors underpinning this variability.ObjectiveThe present research examined the content of adults' attitudes toward children to address these questions.MethodTen studies (N = 4702) identified the factor structure of adults' descriptions of babies, toddlers, and school‐age children and examined how the resulting factors related to a range of external variables.ResultsTwo factors emerged—affection toward children and stress elicited by them—and this factor structure was invariant across the United Kingdom, the United States, and South Africa. Affection uniquely captures emotional approach tendencies, concern for others, and broad positivity in evaluations, experiences, motivations, and donation behavior. Stress relates to emotional instability, emotional avoidance, and concern about disruptions to a self‐oriented, structured life. The factors also predict distinct experiences in a challenging situation—home‐parenting during COVID‐19 lockdown—with affection explaining greater enjoyment and stress explaining greater perceived difficulty. Affection further predicts mentally visualizing children as pleasant and confident, whereas stress predicts mentally visualizing children as less innocent.ConclusionsThese findings offer fundamental new insights about social cognitive processes in adults that impact adult–child relationships and children's well‐being.

Despite the fundamental importance of children in adults’ lives, research has failed to systematically examine the psychological content of adult’s attitudes towards children. This manuscript describes four preliminary (N=1,073) and five main studies (N=2,227) addressing this gap, while also providing a new measure for assessing these attitudes: the Attitudes Towards Children (ATC) scales. After identifying beliefs, feelings, and behaviors that adults spontaneously associate with babies, toddlers, and primary/elementary school-age children, two factors emerged consistently: one factor capturing affection towards them and one capturing stress elicited by them. Focusing on attitude content towards school-age children, we found that affection is related to individual differences in positive affectivity, emotional approach tendencies, and a concern for others, while also predicting broad positivity in evaluations, motivations, and donation behavior specific to children. In contrast, we found that stress is related to individual differences in self-focused emotional instability, emotional avoidance, and concern about disruptions to a structured life. These attitude components also predict parents’ experiences in a challenging situation – home-parenting during Covid-19 lockdown – with affection explaining greater enjoyment, and stress explaining greater perceived difficulty. Furthermore, in a reverse-correlation image classification task, affection predicted mental visualization of children as more confident and less quiet, while stress predicted mental visualization of children as tougher and less innocent. Together, these findings offer fundamental new insights about social cognitive processes that impact children by revealing the importance of distinguishing between affection and stress in attitudes towards them.