Breast pain is common during exercise, occurring in up to 56% of subjects in some surveys. This pain is mainly associated with the movement of breast tissue. In an attempt to analyse this movement and the resulting pain, the movement of the female breast tissue was quantified in four conditions of breast support ("sports bra", "fashion bra", "crop top" and bare breasted) during four different activities (running, jogging, aerobics march and walking). These activities represented general patterns of exercise for adult females in Australian society. All three subjects were healthy, active, young women of varying breast size (12B, 14B & 14C) that were typical of young women. Two of the subjects had noted breast pain whilst exercising. The results showed that wearing external support for the breast tissue reduced absolute vertical movement and maximum downward deceleration force on the breast. Support also reduced perceived pain. When compared to other forms of breast support a "sports bra" (brassiere designed for breast support whilst exercising) provided superior support for the breast in relation to the amplitude of movement, deceleration forces on the breast, and perceived pain. The data indicates that adult females should wear appropriate breast support to reduce perceived breast discomfort or pain. Of the three garments examined in this study, the fitted sports bra provided superior support and pain reduction.