Short bursts of high-intensity physical activity beneficial for bone health in women
Performing 1 to 2 minutes of high-intensity physical activity (PA) daily, equivalent to running in premenopausal women and slow jogging in postmenopausal women, is associated with better bone health, a study has found. Short bursts of bone health-specific high-intensity habitual PA can be quantified from accelerations measured at the wrist using accelerometry-based activity monitors.
The study included 1,218 premenopausal and 1,316 postmenopausal healthy women. Habitual PA was monitored over 7 days using accelerometry-based activity monitors (100 Hz). Time spent at intensities beneficial to bone health (≥750 milligravitational units [mg] and ≥1000 mg) were evaluated from the resulting raw tri-axial acceleration data averaged over 1-second epochs.
Associations between categories of time (<1, 1 to 2 and ≥2 minutes) spent above the intensity thresholds and calcaneal quantitative ultrasound measures of bone health (bone mineral density T-score [BMDT-score], speed of sound [SOS] and broadband ultrasound attenuation [BUA]) were analysed.
Results showed that compared with <1 minute, spending 1 to 2 or ≥2 minutes/day at intensities ≥1000 mg in premenopausal and at ≥750 mg in postmenopausal women was positively associated with BMDT-score, SOS and BUA.
Affecting women more than men, osteoporosis is a brittle bone disease characterized by loss of bone mass and structural deterioration of bone tissue. The disease may result in significant pain, disability, loss of independence and increased risk of morbidity, especially in the first 6 months after fracture. Given that physical activity is a highly modifiable risk factor for osteoporosis development, it is important to identify strategies that may optimize bone health in both pre- and postmenopausal women. [Lancet 2002;359:1929–36; http://www.ilcuk.org.uk/images/up loads/publication-pdfs/pdf_pdf_143.pdf]
“Future research should further exploit high-resolution accelerometry-based activity monitor data to determine the optimal temporal characteristics of PA for bone health to inform the development of manageable and effective PA interventions,” researchers said.