Parent/Child training to increase preteens' calcium, physical activity, and bone density: a controlled trial.

Abstract

PURPOSE:

To test effects of parent/child training designed to increase calcium intake, bone-loading physical activity (PA), and bone density.

DESIGN:

Two-group randomized controlled trial.

SETTING:

Family-based intervention delivered at research center.

SUBJECTS:

117 healthy children aged 10-13 years (58.1% female, 42.7% Hispanic, 40.2% White). Ninety-seven percent of participants had at least one parent graduate from high school and 37.2 % had at least one parent graduate from a 4-year university.

INTERVENTION:

Children and parents were randomly assigned to diet and exercise (experimental) or injury prevention (control) interventions. Children were taught in eight weekly classes how to engage in bone-loading PA and eat calcium-rich foods or avoid injuries. Parents were taught behavior management techniques to modify children's behaviors.

MEASURES:

Measures at baseline and at 3, 9, and 12 months included 24-hour diet and PA recalls, and bone mineral density (BMD) by dual-energy x-ray absorptiometry.

ANALYSIS:

Analysis of variance and generalized estimating equations (GEE) assessed group by time differences. Comparisons were conducted separately for boys and girls.

RESULTS:

For boys, cross-sectional differences between experimental and control groups were achieved for 3- and 9-month calcium intake (1352 vs. 1052 mg/day, 1298 vs. 970 mg/day, p < .05). For girls, marginal cross-sectional differences were achieved for high-impact PA at 12 months (p < .10). For calcium intake, a significant group by time interaction was observed from pretest to posttest for the full sample (p = .008) and for girls (p = .006) but not for boys. No significant group by time differences in calcium were observed across the follow-up period. No group by time differences were observed for high-impact PA. Among boys, longitudinal group by time differences reached significance for total hip BMD (p = .045) and femoral neck BMD (p = .033), even after adjusting for skeletal growth. Similar differential increases were observed among boys for bone mineral content (BMC) at the hip (p = .068) and total body (p = .054) regions. No significant group by time interaction effects were observed for girls at any bone site for BMD. For BMC, control girls showed a significant increase (p = .03) in spine BMC compared to intervention girls.

CONCLUSION:

This study demonstrated that parent/preteen training can increase calcium intake and attenuate the decline in high-impact PA. Results suggest that more powerful interventions are needed to increase activity levels and maximize bone mineral accrual during preadolescent years.

• Authors: Melbourne F Hovell, Jeanne F Nichols, Veronica L Irvin, Katharine E Schmitz, Cheryl L Rock, C Richard Hofstetter, Kristen Keating, Lori J Stark
• Journal: American journal of health promotion : AJHP (Am J Health Promot) 2009 Nov-Dec Vol. 24 Issue 2 Pg. 118-28 ISSN: 0890-1171 [Print] United States
• PMID: 19928484 (Publication Type: Journal Article, Randomized Controlled Trial, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• Calcium

Topics

• Adolescent
• Bone Density
• Calcium (administration & dosage)
• Child
• Cross-Sectional Studies
• Diet
• Exercise
• Female
• Health Promotion (methods)
• Hispanic or Latino (education)
• Humans
• Male
• Parents
• Racial Groups (education)
• Socioeconomic Factors
• Time Factors
• Wounds and Injuries (prevention & control)