Short-termed changes in quantitative ultrasound estimated bone density among young men in an 18-weeks follow-up during their basic training for the Swiss Armed Forces

Michael Strässle; Jonas Grossmann; Patrick Eppenberger; Alexander Faas; Ivanka Jerkovic; Joël Floris; Lena Öhrström; Gülfirde Akgül; Lafi Aldakak; Frank Rühli; Nicole Bender; Kaspar Staub

doi:10.7717/peerj.15205

Short-termed changes in quantitative ultrasound estimated bone density among young men in an 18-weeks follow-up during their basic training for the Swiss Armed Forces

PeerJ. 2023 Apr 6:11:e15205. doi: 10.7717/peerj.15205. eCollection 2023.

Authors

Michael Strässle^{1

2

3}, Jonas Grossmann^{4

5}, Patrick Eppenberger², Alexander Faas⁶, Ivanka Jerkovic⁶, Joël Floris², Lena Öhrström², Gülfirde Akgül², Lafi Aldakak², Frank Rühli^{2

7}, Nicole Bender², Kaspar Staub^{2

7}

Affiliations

¹ Kantonsspital St. Gallen, St. Gallen, Switzerland.
² Institute of Evolutionary Medicine, University of Zurich, Zurich, Switzerland.
³ Medical Faculty, University of Zürich, Zurich, Switzerland.
⁴ Functional Genomics Center Zurich, Eidgenössische Technische Hochschule Zürich, Zürich, Switzerland.
⁵ SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland.
⁶ Swiss Armed Forces, Bern, Switzerland.
⁷ Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland.

Abstract

Background: Quantitative Ultrasound (QUS) methods have been widely used to assess estimated bone density. This study aimed to assess changes in estimated bone density in association with changes in body composition, physical activity, and anthropometry.

Methods: We examined changes in anthropometry, body composition, and physical activity associated with changes in estimated bone mineral density (measured using quantitative ultrasound with a heel ultrasound device indicating broadband ultrasound attenuation BUA and speed of sound SOS) in a follow-up sample of n = 73 young men at the beginning and again 18 weeks later at the end of basic military training.

Results: At the end of the basic training, the subjects were on average significantly heavier (+1.0%), slightly taller (+0.5%) and had a higher fat mass (+6.6%) and grip strength (+8.6%). A significant decrease in mean physical activity (-49.5%) and mean estimated bone density calculated with BUA (-7.5%) was observed in the paired t-test. The results of the multivariable linear regressions (backward selection) show that changes in skeletal muscle mass (delta = 2nd measurement minus 1st measurement) have negative and body weight (delta) have positive association with the speed of sound SOS (delta), while fat mass (delta) and physical activity (delta) had the strongest negative associations with estimated bone mineral density (delta). In particular, we found a negative association between fat mass (delta) and estimated bone mineral density (delta, estimated with BUA).

Conclusion: Our study suggests that estimated bone density from the calcaneus can change within a few months even in young and mostly healthy individuals, depending upon physical activity levels and other co-factors. Further studies including other troop types as control groups as well as on women should follow in order to investigate this public health relevant topic in more depth. To what extent the estimated bone density measurement with quantitative ultrasound is clinically relevant needs to be investigated in further studies.

Keywords: Bone health; Follow-up; Young adults.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Body Weight
Bone Density* / physiology
Calcaneus* / diagnostic imaging
Education
Female
Follow-Up Studies
Heel / diagnostic imaging
Humans
Male
Military Personnel* / education
Switzerland
Ultrasonography* / methods

Grants and funding

The work has been supported by the Mäxi Foundation Zürich (Grantee Frank Rühli). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.