24 September 2020
2 min of reading
Source / Disclosures
Elhakeem does not report material financial information. Please see the study for relevant financial information from all other authors.
High-intensity physical activity during the first few years of life can help prevent osteoporosis and maximize maximum hip strength later on, according to data published in JAMA Network Open.
“Peak bone mass occurs in young adulthood and is considered an indicator of the risk of fractures and osteoporosis in old age,” Ahmed Elhakeem, PhD, of the University of Bristol in the UK, he said Healio Rheumatology. “It is therefore important to identify modifiable factors in early childhood that could affect peak bone strength.”
To examine the association between physical activity of varying intensity during adolescence with peak hip strength in adulthood, Elhakeem and colleagues analyzed data from the Avon Longitudinal Study of Parents and Children. According to the researchers, this prospective birth cohort study initially enrolled 15,454 pregnant women living in the catchment area – three health authorities in South West England – with an expected delivery date between 1 April 1991 and 31 December 1992. From this cohort, a total of 15,589 babies were delivered, of which 14,901 were alive at the age of 1.
For their analysis, Elhakeem and colleagues included 2,569 healthy children with valid physical activity measurements, recorded during clinical evaluation, for at least one age – 12, 14, 16, or 25 years – as well as up to four repeated accelerometric assessments. Trajectories obtained through accelerometer assessments allowed researchers to measure time spent in moderate to vigorous, light-intensity physical activity, measured in minutes per day. The main outcome was the bone mineral density of the femoral neck at age 25, as assessed by dual-energy radiographic absorptiometry scans of the hip.
According to the researchers, male participants spent more time in moderate to vigorous intensity activity at each age and had higher adult femoral neck bone mineral density than female participants, who made up 62% of the cohort. included.
For both boys and girls, the researchers identified three subgroups of moderate to vigorous intensity trajectory and three subgroups of light intensity trajectory. Regarding the moderate to vigorous intensity trajectories, 85% of male participants belonged to the low adolescent subgroup, with only 6% and 9% in the early adolescent and mid adolescent high subgroups, respectively. Meanwhile, for the moderate to vigorous intensity trajectories among female participants, 73% were in the low adolescent / low adult subgroup, 8% in the low adolescent / tall adult subgroup, and 19% were classified as high. teenager.
Researchers classified light intensity physical activity trajectories into low, moderately decreasing, and sharply decreasing non-linear subgroups for males and females.
Femoral neck bone mineral density in male participants was higher in the early adolescent subgroup (BMD = 0.38 g / cm2; 95% CI, 0.11-0.66) and the subgroup of medium to tall adolescents (BMD = 0.33 g / cm2; 95% CI, 0.07-0.6), compared to the subgroup of short adolescents. Femoral neck bone mineral density among female participants was higher in the high adolescent subgroup (BMD = 0.28 g / cm2; 95% CI, 0.15-0.41), but not in the low-high-adolescent adult subgroup (BMD = -0.12 g / cm2; 95% CI, –0.44 to 0.2), compared to the low number adolescent / low adult subgroup.
Additionally, a sensitivity analysis that uses a negative outcome control variable to examine unmeasured confounding supports these results, the researchers wrote. Light intensity trajectories were not associated with femoral neck bone mineral density. For example, the density differences between the high-decrease and non-linear low subgroups were 0.16 g / cm2 (95% CI, –0.08 to 0.4) in male participants and 0.2 g / cm2 (95% CI, –0.05 to 0.44) in female participants.
“The findings highlight adolescence as a potentially important period for bone development through high-intensity exercise, which could benefit future bone health and prevent osteoporosis in old age,” Elhakeem said. “We have also confirmed other studies showing MVPA levels decline during adolescence. Our results show that it is really important to support young people to stay active at this age. “