Children with Down syndrome (DS) who received inspiratory muscle training (IMT) plus aerobic exercise training demonstrated more significant improvements in physical fitness compared with those with DS who received aerobic exercise training alone, according to the results of a recent randomized controlled trial (ClinicalTrials.gov identifier: NCT04767412) published in the Archives of Physical Medicine and Rehabilitation.
Recognizing that children with DS frequently have low peak aerobic capacity, heart rate, and muscle strength — all of which are considered key factors contributing to lower physical fitness in this population — the investigators sought to assess the impact of aerobic exercise on physical fitness and the effect of IMT on respiratory muscle strength in these individuals. Additionally, the researchers sought to compare the effectiveness of combined aerobic exercise plus IMT vs aerobic exercise alone in improving physical fitness among children with DS.
A total of 40 girls and boys between 7 and 10 years of age (mean age, 7.8±1.5 years) were enrolled in the current study. The participants were randomly and equally divided into 2 groups (A and B). The study was conducted between October 2020 and December 2020. All of the patients were recruited from a private physical therapy center located in Egypt. Study inclusion criteria were as follows: (1) BMI: 5th percentile to less than 85th percentile; (2) ability to understand and follow verbal commands and instructions used during training and tests.
All of the study participants in groups A and B received 30 minutes of aerobic exercise training 3 times per week for 12 weeks. Those in group B also received an additional 30 minutes of IMT prior to each aerobic exercise session. The main outcome measure was physical fitness of the participants, which was evaluated prior to and after the treatment via use of the following tools: (1) the 6-minute walk test (6MWT), to assess aerobic capacity; (2) the Gio Digital Pressure Gauge, to detect the intensity of IMT and improvement in respiratory muscle strength following the training program; and (3) the Brockport physical fitness test (BPFT), which provides a health-related assessment of aerobic functioning in children with disabilities.
The investigators evaluated the results of the following measures: maximal inspiratory pressure (MIP); maximal expiratory pressure (MEP); submaximal aerobic endurance using the 6MWT strength; and endurance using the curl-up, dumbbell press, trunk lift, standing long jump, seated push-up, pull-up, flexed-arm hang, and back saver sit and reach tests. Per post hoc within-group analysis, a statistically significant difference (P <.05) for all of these measures was reported in the 2 groups.
Following use of the intervention, participants in group B demonstrated significant improvements in MEP; MIP; and the results of the 6MWT, curl-up, dumbbell press, trunk lift, standing long jump, seated push-up, pull-up, flexed-arm hang, and back saver sit and reach tests (P <.05 for all), compared with participants in group A.
A main limitation of the current study is its small sample size, because of the exclusion of children who engaged in regular physical activity. Further, the enrollment of children between the ages of 7 and 10 years only might limit the generalizability of the results.
The investigators concluded that both aerobic exercise training and IMT “significantly improved physical fitness in children with DS,” with the combination of aerobic and inspiratory muscle training resulting in the most significant improvement. Based on their results, they recommended that further research investigate “the effect of IMT on quality of life” and “on long-term goals in children with DS.”
Elshafey MA, Alsakhawi RS. Inspiratory muscle training and physical fitness in children with Down syndrome: randomized control trial. Arch Phys Med Rehabil. Published online May 6, 2022. doi:10.1016/j.apmr.2022.04.005