FEMALE SWIMMERS HAVE LOW BONE-MINERAL CONTENT AND BONE-DENSITY
Stanforth, D., Stanforth, P. R., Stults-Kolehmainen, M. A., & Crim, B. N. (2014). Female collegiate athlete bone mineral content/density: Differences among sports and changes across three years. Medicine & Science in Sports & Exercise, 45(5), Supplement abstract number 2365.
This descriptive study compared the total bone-mineral content and bone-density among female collegiate athletes in five sports and analyzed changes in bone-mineral content and bone-density across three years. Between 2003 and 2010, female athletes, 18-23 years of age, from basketball (N = 38), soccer (N = 47), swimming (N = 52), track sprinters/jumpers (N = 49), and volleyball (N = 26) had their bone-mineral content and arm, leg, pelvis, spine, and total bone-density assessed using whole body dual emission x-ray absorptiometry (DXA) at pre-season (August/September) and post-season (near end of their respective seasons). A restricted maximum-likelihood linear mixed model regression analysis was performed to determine if bone-mineral content and bone-density differed by sport over a multi-year period.
Basketball had greater bone-mineral content than all other sports. Volleyball had greater bone-mineral content than soccer, track sprinters/jumpers, and swimming. Soccer and track sprinters/jumpers had greater bone-mineral content than swimming. Basketball had greater leg bone-density than volleyball. Swimming had lower leg, pelvis, spine, and total bone-density than all other sports. Volleyball had greater arm, leg, and total bone-density than soccer, and greater leg bone-density than track sprinters/jumpers. Track sprinters/jumpers had greater arm bone-density than soccer. Significant changes over three years included: 1) increases in total bone-mineral content from year 1 to 2 to 3 in basketball and track sprinters/jumpers and from year 1 to 2 and 3 in volleyball. There were no changes in any bone-density measure over the three years.
Implication. Basketball had the highest bone-mineral content and bone-density measures while swimming had the lowest bone-mineral content and bone-density measures. Basketball, track sprinters/jumpers, and volleyball increased bone-mineral content, but not bone-density over three years. The low recordings of swimmers are indicative of the specific anatomical effects that result from participation in that sport.