Physical Activity for Bone Health: How Much and/or How Hard?

Purpose: High-impact physical activity is associated with bone health, but higher volumes of lower-intensity activity may also be important. The aims of this study were to: 1) investigate the relative importance of volume and intensity of physical activity accumulated during late adolescence for bone health at age 23 yr; and 2) illustrate interpretation of the results.

Methods: This is a secondary analysis of data from the Iowa Bone Development Study, a longitudinal study of bone health from childhood through to young adulthood.

An 8-Year Longitudinal Analysis of Physical Activity and Bone Strength From Adolescence to Emerging Adulthood: The Iowa Bone Development Study.

Purpose: Most pediatric physical activity and bone health research has focused on the period immediately around puberty; few have addressed bone structural strength outcomes. This study assessed the magnitude and consistency of the longitudinal relationships between device-measured vigorous-intensity physical activity (VPA) and structural bone strength outcomes across adolescence to emerging adulthood.

Methods: Participants with 3 to 5 bone scans between the age of 11 and 19 years were studied (N = 439, 220 females, 1838 records).

Calibration of the global physical activity questionnaire to Accelerometry measured physical activity and sedentary behavior.

Background: Self-report questionnaires are a valuable method of physical activity measurement in public health research; however, accuracy is often lacking. The purpose of this study is to improve the validity of the Global Physical Activity Questionnaire by calibrating it to 7 days of accelerometer measured physical activity and sedentary behavior.

Methods: Participants (n = 108) wore an ActiGraph GT9X Link on their non-dominant wrist for 7 days.

Objectively measured physical activity predicts hip and spine bone mineral content in children and adolescents ages 5-15 years: iowa bone development study.

This study examined the association between physical activity (PA) and bone mineral content (BMC; gram) from middle childhood to middle adolescence and compared the impact of vigorous-intensity PA (VPA) over moderate- to vigorous-intensity PA (MVPA). Participants from the Iowa bone development study were examined at ages 5, 8, 11, 13, and 15 years (n = 369, 449, 452, 410, and 307, respectively). MVPA and VPA (minutes per day) were measured using ActiGraph accelerometers.

Effects of moderate-to-vigorous intensity physical activity on overnight and next-day hypoglycemia in active adolescents with type 1 diabetes.

Objective: Physical activity (PA) provides many benefits to adolescents with type 1 diabetes; however, these individuals tend to have lower fitness and PA levels than their disease-free counterparts. The purpose of this study was to examine the acute temporal associations between moderate-to-vigorous intensity PA (MVPA) and hypoglycemia (continuous glucose monitor [CGM] reading ≤70 mg/dL).

Research Design And Methods: Nineteen participants (53% females) 14-20 years old with type 1 diabetes were recruited.