JMIR Publications

ABSTRACT

Background:

Low mechanical loading of the bones of wheelchair (WC) users leads to low bone mineral density (BMD) and increased risk of bone fractures and associated complications. High load resistance training of the upper body is one way of achieving mechanical loading of the lumbar spine and the hip bones. In addition, maintaining good nutritional status with key nutrients for bone remodelling, i.e., vitamin D and calcium, is important for bone accrual.

Objective:

The primary objective is to investigate the effect of 24-weeks’ high-load resistance training combined with nutritional optimisation, on lumbar spine BMD. Secondary objectives are to investigate the effects of the intervention on 1) bone and physical health parameters such as bone turnover blood markers, nutritional status, body composition and maximal muscular strength, as well as 2) on the psychological dimensions motivation and mental health.

Methods:

In this randomised controlled trial (RCT), we aimed to include 60 WC users with non-progressive impairments. Participants were randomly allocated to 24 weeks of either a) high-load resistance training and nutrition optimisation, or b) nutrition optimisation only, stratified by sex and sport activity status. The training programme consisted of three weekly sessions of six exercises periodised in low-, moderate-, and high-load phases. The nutritional optimisation aimed to ensure sufficient protein, vitamin D and calcium intake. BMD and body composition, maximal muscular strength, nutritional, physical, and mental health status, were assessed at baseline, midpoint and post-intervention. Furthermore, follow-up assessments of a subgroup were conducted at 6-18 months post-intervention. This protocol was approved by the Regional Committee for Medical and Health Research Ethics.

Results:

Recruitment occurred between November 2022 and November 2023. A total of 68 WC users were screened for eligibility, of which 45 participants were enrolled and allocated to one of the study groups (24 training, 21 control). At midpoint and post-intervention, 37 (17 and 19, respectively) and 33 (14 and 19, respectively) participants were assessed, respectively. Analysis of the data collected at the screening visit has commenced as of spring 2024, while analyses on data collected at baseline and retest visits began in autumn 2024. Publication of the results of this study are expected in ultimo 2025.

Conclusions:

This protocol presents the first RCT on a high-load resistance training intervention in WC users, with focus on bone-, physical- and mental health. The results will contribute to new knowledge in exercise science for this population and generate novel hypotheses for future studies. Clinical Trial: This study was registered in ClinicalTrials.gov (NCT05615402) on Nov 14, 2022, as well as OpenScienceFramework (doi.org/10.17605/OSF.IO/SE2TB) on Jan 04, 2023.