Table 2. Mean ± standard deviation of age, breast size, body mass index (BMI) frequency of sports bra use and training hours between participants who did not report (no injury) and did report (injury) contact breast injuries and frictional breast injuries. Variable Contact breast injuries Frictional breast injuries No injury Injury p-value No injury Injury p-value Age (years) 25.5 ± 9.2 26.1 ± 9.7 0.578 25.0 ± 8.8 28.3 ± 11.0 0.011 Breast size (rank) * 1.2 ± 0.5 1.5 ± 0.6 <0.001 1.2 ± 0.5 1.6 ± 0.6 <0.001 BMI (kg/m2) 22.6 ± 3.0 24.1 ± 3.8 <0.001 22.8 ± 3.0 23.8 ± 4.1 0.123 Sports bra use (rank) # 1.1 ± 0.5 1.2 ± 0.6 0.098 1.2 ± 0.5 1.2 ± 0.7 0.951 Training (hours) 12.2 ± 7.8 12.1 ± 9.8 0.257 11.9 ± 8.1 13.3 ± 9.6 0.211 # Frequency of sports bra use ranked from 1 (always) to 5 (never). *Breast size ranked from 1 (small breasts, < 350 ml per breast) to 4 (hypertrophic breasts, > 1200 ml per breast).