Appropriate sports bras are crucial to limit potential breast pain and ptosis. In an attempt to optimize breast support during exercise, manufacturers now produce activity level-specific sports bras. However, until breast movement across activity levels is understood, the criterion for such apparel is unknown. Therefore, the aim of this study was to quantify multi-planar breast displacement across treadmill activity levels and breast support conditions. Twenty-one D cup participants had markers attached to their nipples and trunk to calculate relative 3D breast displacement. Supported and unsupported mediolateral, anterioposterior, vertical, and resultant breast displacement was assessed during treadmill walking up to maximum running. Unsupported resultant breast displacement increased from 4.2 ± 1.0 cm during walking to 15.2 ± 4.2 cm during running. There was no change in breast displacement amplitude or direction as running speed increased above 10 km · h−1, with vertical breast displacement then accounting for ∼50% of overall displacement. While breast support was effective in reducing the amplitude of breast displacement during walking and running, the direction was unaffected. In conclusion, instead of activity level-specific breast support, future research should identify multi-planar breast kinematics during various sporting modalities. This might lead to production of a sports-specific bra to reduce the negative consequences of breast movement.
A correctly fitting bra is essential for good health; this study investigates the use of professional bra fitting criteria to establish best-fit in an underwire bra commonly sold in the UK. A comparison was made between women's bra size as measured by the traditional bra fitting method with their recommended bra size based on professional bra fitting criteria. Forty-five female participants were recruited; their mode self-reported bra size was 34DD. Participants were measured in their own bra using the traditional bra-fitting method to establish their ‘traditional size’. A ‘best-fit’ bra size was recorded for participants based on professional bra fitting criteria. Significant differences were found between traditional and best-fit cup and band sizes (p < 0.001); the traditional method of bra fitting overestimated band size and underestimated cup size. As band size increased the traditional method also became more inaccurate (p < 0.001). It is recommended that women are educated in assessing their own bra fit using professional bra fitting criteria and less emphasis placed on determining absolute bra size. Practitioner Summary: This is the first study to investigate using professional bra fitting criteria to establish best-fit in an underwired bra commonly sold in the UK. The traditional method of bra fitting was found to be inadequate, especially for larger-breasted women; the use of professional bra fitting criteria should be encouraged.
Electromyograms used to assess neuromuscular demand during high-velocity tasks require normalization to aid interpretation. This paper posits that, to date, methodological approaches to normalization have been ineffective and have limited the application of electromyography (EMG). There is minimal investigation seeking alternative normalization methods, which must be corrected to improve EMG application in sports. It is recognized that differing normalization methods will prevent cross-study comparisons. Users of EMG should aim to identify normalization methods that provide good reliability and a representative measure of muscle activation. The shortcomings of current normalization methods in high-velocity muscle actions assessment are evident. Advances in assessing alternate normalization methods have been done in cycling and sprinting. It is advised that when normalizing high-intensity muscle actions, isometric methods are used with caution and a dynamic alternative, where the muscle action is similar to that of the task is preferred. It is recognized that optimal normalization methods may be muscle and task dependent.
Although breast pain has been related to vertical breast displacement and velocity, the influence of breast support on multi-planar breast kinematics and breast comfort has yet to be ascertained. The aims of this study were to investigate multi-planar breast displacement, velocity, and acceleration with and without breast support during running and to establish the correlation with breast comfort. Fifteen females ran at 2.8 m · s−1 in no bra, an everyday bra, and a sports bra. Three-dimensional coordinates of breast and body markers were tracked during ten gait cycles and following each trial the participants rated their breast comfort. Relative breast displacement was calculated and derived for velocity and acceleration. Vertical breast displacement, velocity, and acceleration peaked at, before, and after mid-stance, respectively. The patterns of displacement and velocity trajectories were unaffected by increasing breast support, though the magnitudes were significantly reduced. The magnitude and trajectory of breast acceleration was unaffected by increasing breast support and showed no correlation with comfort. Breast velocity displayed the strongest relationship to comfort (r = 0.61). Considerable mediolateral and anteroposterior breast kinematics were identified, suggesting that future studies and bra design may benefit from three-dimensional analysis. In conclusion, improvements in breast support may be defined by reductions in breast velocity and displacement.
Changes in ground reaction forces that result from different breast support conditions may have implications for sports performance and transmission of forces through the skeleton. The aim of this investigation was to compare kinetic variables and breast motion in a no-bra, everyday-bra and two sports-bra conditions. Following ethical approval, eight female participants with D-cup breasts had retro-reflective markers placed on the left and right nipples, anterior superior iliac spines and clavicles. Five calibrated ProReflex infra-red cameras (100 Hz; Qualisys) measured 3-D displacement of markers and synchronised kinetic data were collected using a force platform (500 Hz, Kistler 9281CA). A repeated measures one-way ANOVA revealed a significantly higher medial impact force in the no-bra condition (0.15 times body weight) compared with the compression sports-bra condition (0.12 times body weight) (F = 3.64 3,21, p = 0.03). Findings suggest that inadequate breast support affects a female's running kinetics, which may have negative physiological consequences on sports performance.
Breast pain has been investigated in clinical populations; however we have yet to understand the prevalence and severity of this condition in the general population to determine whether more should be done to minimize the impact of this condition on women's quality of life. Therefore, this study investigated the prevalence, severity, and impact of breast pain on quality of life and factors associated with breast pain in a normal population sample. 1,659 females (34.1 ± 13.2 years) completed the Breast Pain Questionnaire online, providing information on demographics, duration, frequency, and severity of breast pain, its association with the menstrual cycle, relieving, and aggravating factors and the impact on quality of life. Over half the sample (51.5%) experienced breast pain, with a severity similar to that reported in clinical populations. There was a higher prevalence of breast pain in older participants, larger breasted participants and those who were less fit and active. Of symptomatic participants, 41% and 35% reported breast pain affecting quality of life measures of sex and sleep and 10% of symptomatic participants had sufferer for over half their lives. The results of this study suggest that breast pain is a significant issue within the general population and yet this is the first study to investigate it. It is concluded that this condition warrants increased investigation, awareness, and treatment. The reported relationship between breast pain and fitness/activity levels may offer an alternative treatment in the form of exercise intervention strategies to reduce breast pain.