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 x 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.

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.

This study aimed to assess the trajectory of breast displacement in 3 dimensions during walking and running gait, as this may improve bra design and has yet to be reported. Fifteen D-cup participants had reflective markers attached to their nipples and trunk to monitor absolute and relative breast displacement during treadmill walking (5 kph) and running (10 kph). During the gait cycle, the breast followed a figure-of-eight pattern with four movement phases. Despite a time lag in resultant breast displacement compared with the trunk, similar values of breast displacement were identified across each of the four phases. Fifty-six percent of overall breast movement was vertical, suggesting that 3-D assessment and the elimination of trunk movement in 6 degrees of freedom are essential to accurately report breast displacement during the gait cycle.

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.

Comparisons of breast support requirements during overground and treadmill running have yet to be explored. The purpose of this study was to investigate 3D breast displacement and breast comfort during overground and treadmill running. Six female D cup participants had retro-reflective markers placed on the nipples, anterior superior iliac spines and clavicles. Five ProReflex infrared cameras (100 Hz) measured 3D marker displacement in four breast support conditions. For overground running, participants completed 5 running trials (3.1 m/s ± 0.1 m/s) over a 10 m indoor runway; for treadmill running, speed was steadily increased to 3.1 m/s and 5 gait cycles were analyzed. Subjective feedback on breast discomfort was collected using a visual analog scale. Running modality had no significant effect on breast displacement (p> .05). Moderate correlations (r= .45 to .68,p< .05) were found between breast discomfort and displacement. Stride length (m) and frequency (Hz) did not differ (p< .05) between breast support conditions or running modalities. Findings suggest that breast motion studies that examine treadmill running are applicable to overground running.