Relationships of Physical Activity and Calcium Intake on Fat Mass Development in Growing Girls: 2466: Board #49 May 31 8:00 AM - 9:30 AM

Gunter, Katherine B.1; Piccinin, Andrea M.1; Amstedt, Hawley C.2; Snow, Christine M. FACSM1

Medicine & Science in Sports & Exercise:
doi: 10.1249/01.mss.0000322979.50865.c2
G-14 Free Communication/Poster - Children and Adolescents 2: MAY 31, 2008 7:30 AM - 11:00 AM ROOM: Hall B
Author Information

1Oregon State University, Corvallis, OR. 2Loyola Marymount University, Los Angeles, CA.


(No relationships reported)

Epidemiological research indicates that people with higher calcium intakes seem to have lower body weight or fat. However the relationship between calcium intake and body composition has not been investigated in growing children.

PURPOSE: The aim of this investigation was to evaluate relationships of physical activity and calcium intake on fat mass development in growing girls.

METHODS: 102 girls aged 6-10 (mean=8.1) at baseline were evaluated annually over 5 years. Physical activity (hours/week), average energy intakes (Kcal/day), and calcium intake (mg/day) were assessed by validated questionnaires. Standing height, sitting height and weight were assessed and body composition was determined by DXA at each visit. Years from peak height velocity were used as a biological maturity age indicator. Multilevel random effects models were used to test the relationship.

RESULTS: After adjusting for maturation, girls at peak height velocity have, on average, 13.3 kg of fat mass that increases significantly by approximately 1.24 kg per year. Maturity adjusted average calorie and calcium intakes, and hours of physical activity per week decrease significantly for each year of age (p<0.05). Neither fat mass at baseline, nor its trajectory over time, are predicted by the trajectories for calorie or calcium intake, or hours of physical activity. However, girls with higher fat mass than expected at a particular occasion (assuming a linear trajectory), have lower calorie and calcium intakes than expected (p<0.05).

CONCLUSIONS: This finding lends support to the idea that higher calcium intakes may have a beneficial effect on body composition in growing girls. Further, the mechanism for lower than expected calcium may be insufficient energy intake among this population.

©2008The American College of Sports Medicine