A systematic literature review of evidence for the use of assistive exoskeletons in defence and security use cases.

Advances in assistive exoskeleton technology, and a boom in related scientific literature, prompted a need to review the potential use of exoskeletons in defence and security. A systematic review examined the evidence for successful augmentation of human performance in activities deemed most relevant to military tasks. Categories of activities were determined a priori through literature scoping and Human Factors workshops with military stakeholders. Workshops identified promising opportunities and risks for integration of exoskeletons into military use cases. The review revealed promising evidence for exoskeletons' capacity to assist with load carriage, manual lifting, and working with tools. However, the review also revealed significant gaps in exoskeleton capabilities and likely performance levels required in the use case scenarios. Consequently, it was recommended that a future roadmap for introducing exoskeletons to military environments requires development of performance criteria for exoskeletons that can be used to implement a human-centred approach to research and development.

We assessed the state-of-the-art for the use of wearable assistive exoskeletons in UK defence and security use cases. A full systematic review of the literature was undertaken, informed by use cases developed in military stakeholder workshops. Clear gaps in exoskeleton capability and use case requirements were identified, leading to recommendations for future work.

There are two sides to every story: implications of asymmetry on breast support requirements for sports bra manufacturers.

This study aimed to investigate: (1) the prevalence and magnitude of breast movement asymmetry, (2) the interaction between static and dynamic breast asymmetry and (3) the influence of sports bras on breast asymmetry during running. Position data were collected from 167 females whilst treadmill running and then a sub-group of 12 participants in different bra conditions. Breast movement asymmetry existed in 89% of participants, with resultant static breast position asymmetry larger in participants displaying dynamic asymmetry. Asymmetry was most commonly caused (60% to 75%) by greater movement of the left breast. No significant relationships were found between asymmetry and bra size or breast pain. Sports bras reduced asymmetry prevalence from 75% to 33% of participants in the antero-posterior direction but only from 75% to 67% of participants in the infero-superior direction. The magnitude of range-of-motion asymmetry reduced from 67 mm with no bra to between 6 and 64 mm in-bra in the infero-superior direction, with the best performing bra incorporating encapsulating cups and adjustable straps and underband. It is recommended that sports bras allow underband and strap adjustment to facilitate individual breast support and that asymmetry is considered when designing and fitting bras, which could utilise resultant asymmetry measured statically.

Breast education for schoolgirls; why, what, when, and how?

Schools are fundamental settings for health education and adolescent females are an important group for promoting positive breast habits. We surveyed 2089 schoolgirls (11-18 years) to provide evidence for, and guidance on, breast education for schoolgirls. 26% reported negative feelings about their breasts and 87% reported ≥ one breast concern. 72% wanted to know more about breast cancer (69% rating this extremely important). >50% wanted to know more about breast sag and breast pain. Preferred delivery format was age eleven (50%), girls only taught sessions (41%) with female teachers (43%). A need for breast education and delivery preferences was identified.

Understanding key performance indicators for breast support: An analysis of breast support effects on biomechanical, physiological and subjective measures during running.

To assess the effectiveness of breast support previous studies monitored breast kinematics and kinetics, subjective feedback, muscle activity (EMG), ground reaction forces (GRFs) and physiological measures in isolation. Comparing these variables within one study will establish the key performance variables that distinguish between breast supports during activities such as running. This study investigates the effects of changes in breast support on biomechanical, physiological and subjective measures during running. Ten females (34D) ran for 10 min in high and low breast supports, and for 2 min bare breasted (2.8 m·s-1). Breast and body kinematics, EMG, expired air and heart rate were recorded. GRFs were recorded during 10 m overground runs (2.8 m·s-1) and subjective feedback obtained after each condition. Of the 62 variables measured, 22 kinematic and subjective variables were influenced by changes in breast support. Willingness to exercise, time lag and superio-inferior breast velocity were most affected. GRFs, EMG and physiological variables were unaffected by breast support changes during running. Breast displacement reduction, although previously advocated, was not the most sensitive variable to breast support changes during running. Instead breast support products should be assessed using a battery of performance indicators, including the key kinematic and subjective variables identified here.

The Influence of the Breast on Sport and Exercise Participation in School Girls in the United Kingdom.

PURPOSE: Emerging evidence suggests that breasts may be a barrier to physical activity for adult females. With only 12% of the UK 14-year-old girls achieving exercise guidelines, to understand deterrents to exercise in this population, we should consider whether breasts may also influence sport and exercise participation in school girls. This survey-based study investigated the influence of the breast on sport and exercise participation and breast-specific concerns in the UK school girls. METHODS: A survey was developed to assess demographics, breast characteristics, breast-specific concerns in sports, breast knowledge, views on breast education, and sport participation. Chi-squared tests assessed associations between participation and breast size, sports bra use, and breast concerns. RESULTS: Two thousand eighty-nine school girls aged 11-18 years completed the survey, for 97 their breasts had begun developing and 96% reported wearing breast support. Forty-six percent of girls reported that their breasts had some effect on their participation in compulsory sports and exercise, which was more prevalent in girls aged 13-14 years (51%) and in larger-breasted girls (63%). More than 50% reported never wearing a sports bra during sports. Breast concerns were high with 73% reporting ≥1 breast-specific concern in sports; with breast bounce being most prevalent (38%). CONCLUSIONS: As most of the breast concerns raised in this survey could be addressed via education and 87% of girls wanted to know more about breasts, this study demonstrates a need for breast education for school girls, which may reduce the influence of the breast on sport and exercise participation.

Breast motion asymmetry during running.

Breast asymmetry is common in females, despite a similar driving force; dynamic activity may result in asymmetrical breast motion. This preliminary study investigated how breast categorisation (left/right or dominant/non-dominant) may affect breast support recommendations and its relationship with breast pain. Ten females ran on a treadmill at 10 kph in three breast supports (no bra, everyday bra, sports bra). Five reflective markers on the thorax and nipples were tracked using infrared cameras (200 Hz) during five running gait cycles in each breast support. Multiplanar displacements of both breasts were calculated relative to the thorax. Although the maximum individual participant difference was 2.4 cm (mediolaterally) between the left and right breast, no left/right differences were found in any direction or support condition. Notably, correlations between breast pain and anterioposterior breast displacement were stronger with the left breast (r = 0.614) and moderate with the right breast (r = 0.456). Following participant categorisation according to the greatest magnitude of superioinferior breast displacement (dominant breast), results showed significant differences in displacement for all directions across different breast supports. When using breast kinematic data to examine relationships with breast pain or to recommend breast support requirements, data on both breasts should be collected.

Is torso soft tissue motion really an artefact within breast biomechanics research?

For rigid body POSE estimation, any relative movement of the tracking markers on a segment is often referred to as an artefact; however this may be an important part of the signal within breast biomechanics. This study aimed to quantify differences in breast range of motion when calculated relative to the torso segment using either direct or segment optimised POSE estimation algorithms. Markers on the torso and right nipple were tracked using infrared cameras (200 Hz) during five running gait cycles in three breast support conditions (no bra, everyday bra and sports bra). Multiplanar breast range of motion was calculated relative to the torso segment using two POSE estimation algorithms. First, the torso segment was defined using direct POSE estimation (direct). Second, while standing stationary in the anatomical position; the positional data of the torso markers were used to construct the torso using segment optimised POSE estimation (optimised). The torso segment length defined using direct POSE estimation changed significantly by 3.4 cm compared to that of the segment optimisation POSE estimation in the no bra condition. Subsequently, superioinferior breast range of motion was significantly greater (p<0.017) when calculated using direct POSE estimation, within each of the three breast support conditions. Segment optimisation POSE estimation is recommended to minimise any differences in breast motion associated with intra segment deformation between physical activity types. However, either algorithm is recommended when evaluating different breast support garments, as a correctly fitted bra does not cause the torso markers to move relative to each other.

Can axes conventions of the trunk reference frame influence breast displacement calculation during running?

To obtain breast motion relative to the trunk, skin markers are used to define a local coordinate system (trunk), with respect to the global reference frame. This study aimed to quantify any differences in multiplanar breast displacement relative to the trunk using the first axis of rotation as either the mediolateral or longitudinal axis. Ten female participants ran on a treadmill (10 kph) in three different breast supports (no bra, everyday bra, sports bra). Four reflective markers placed on the trunk and right nipple were tracked using eight infrared cameras (200 Hz) during five running gait cycles in each breast support condition. Following marker identification, right breast multiplanar displacements were calculated relative to the trunk using either the mediolateral axis or the longitudinal axis as the first rotational axis to define the orthogonal local coordinate system. Results showed that there was a significant difference (8.2%) in superioinferior breast displacement in the sports bra condition when calculated using different axes conventions for the trunk segment. Furthermore, the greatest magnitude of breast displacement occurred in a different direction depending upon the selection of the first rotational axis. The definition of the primary reference axis of the trunk significantly alters the magnitude of superioinferior breast displacement and therefore it is recommended that the previously reported 'stable' longitudinal axis should be defined as the first rotational axis during running. Caution should also be used as the axes convention influences the magnitude and direction of breast support requirements, which has important implications for bra design.

The influence of ageing on bra preferences and self-perception of breasts among mature women.

The ageing process has both psychological and physiological effects on women, and tactical choices are often made regarding beauty interventions to mask the outward signs of increasing age. The bra is believed to counteract the negative effects of ageing on the breast and alter the perceptions of one's body. Due to the profound anatomical changes to the breast with increasing age, this paper aimed to examine the influence of ageing on women's perceptions of their breasts and their bra preferences. 208 women aged 45-65 years were surveyed about their breasts, their bras and how they felt ageing may have influenced these. The findings showed 80 % of women surveyed had noticed a significant change in their breasts with ageing, just 7 % of the women surveyed were still proud of their breasts and 84 % of women dressed to look younger. Further, over 50 % of respondents would now not wear the bra they had worn in their twenties, indicating a change in bra preferences with age. The bra variables of primary importance to participants were: comfort, the bra's ability to stay in place, optimal fit, appearance under clothing, support, discreetness, shoulder strap design, silhouette, breast shape, fabric and breast lift. These variables are perceived as being influential in the appropriateness of the bra and its social role for mature women; therefore, it is these bra variables that should be the focus of subsequent research regarding the optimisation of bras for women aged 45-65 years.

The relationship between breast size and anthropometric characteristics.

OBJECTIVES: Current clinical selection criteria for mammaplasty use weight-related parameters, and weight loss is recommended as a nonsurgical intervention to reduce breast size. However, research has not firmly established if breast size is related to body size and composition. This study aims to investigate anthropometric characteristics in smaller and larger breasted women and identify predictors of breast mass. METHODS: A bra fitter determined underband and cup size of 93 A to H cup size women (mean ± standard deviation, age 25.7 ± 5.6 years, height 1.67 ± 0.6 cm, and mass 65.6 ± 11.0 kg). Estimations of breast mass (g) were made, and participants were categorized as smaller (<500 g) or larger (>500 g) breasted. Restricted anthropometric profiles determined body mass, height, body mass index (BMI), waist-to-hip ratio, sum of eight skinfolds, subscapular to triceps skinfold ratio, somatotype, percent body fat, fat and fat-free mass, and suprasternal notch to nipple distance. RESULTS: All variables (excluding height, subscapular to triceps skinfold ratio, and age) were significantly greater in larger breasted women. Body mass-related parameters and suprasternal notch to nipple distance were positively related to breast mass, with BMI and suprasternal notch to nipple distance accounting for half of the variance in breast mass. CONCLUSION: Smaller and larger breasted women demonstrate differences in anthropometry, with body mass and BMI demonstrating strong relationships to breast mass. Measures of BMI and suprasternal notch to nipple distance enable predictions of breast mass and suggest that weight-related parameters are not appropriate exclusion criteria for mammaplasty.