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Influence of additional weight on the frequency of kicks in infants with Down syndrome and infants with typical
Gabriela L Santos1, Thaís B Bueno1, Eloisa Tudella1
1Department of Physical Therapy, Universidade Federal de São Carlos, São Carlos, SP, Brazil.
Insights
Adding ankle weights to infants with Down syndrome and typically developing infants improved kicking performance. However, infants with Down syndrome consistently showed lower kicking frequencies, highlighting developmental differences in motor skill acquisition.
Area of Science:
- Pediatric physical therapy
- Infant motor development
- Developmental disabilities
Background:
- Infants with Down syndrome experience motor skill delays, including kicking, a precursor to gait.
- Early physical therapy interventions are crucial for addressing these delays.
Purpose of the Study:
- To compare the effect of added ankle weight on kicking frequency in infants with Down syndrome and typical development.
- To analyze kicking frequency at 3 and 4 months of age under different experimental conditions.
Main Methods:
- Five infants with Down syndrome and five typically developing infants (3-4 months old) were filmed.
- Four conditions were tested: training, baseline, weight (1/3 lower limb weight), and post-weight.
Main Results:
- Infants with Down syndrome exhibited significantly lower kicking frequencies than typically developing infants across all measures (p<0.05).
- Both groups showed significant improvements in kick contact and success frequency after weight application (p<0.001).
Conclusions:
- Ankle weights served as a stimulus, enhancing kicking performance and target-directedness through repetition for both groups.
- Despite improvements, infants with Down syndrome maintained lower kicking frequencies, indicating persistent developmental differences.
Background:
Infants with Down syndrome present with organic and neurological changes that may lead to a delay in the acquisition of motor skills such as kicking, a fundamental skill that is a precursor of gait and is influenced by intrinsic and extrinsic factors. Therefore, this movement should be taken into account in early physical therapy interventions in infants.
Objective:
To analyze and to compare the effect of additional weight on the frequency of kicks in infants with Down syndrome and infants with typical development at 3 and 4 months of age.
Method:
Five infants with Down syndrome and five with typical development at 3 and 4 months of age were filmed. The experiment was divided into four experimental conditions lasting 1 minute each: training, baseline, weight (addition of ankle weight with 1/3 the weight of the lower limb), and post-weight.
Results:
There were significant differences between groups for all variables (p<0.05), with lower frequencies observed for infants with Down syndrome in all variables. There were significant differences between the experimental conditions baseline and post-weight (p<0.001) for both groups in the frequency of contact and success, with a higher frequency in the post-weight condition.
Conclusions:
The weight acted as an important stimulus for both groups, directing the kicks toward the target and improving the infants' performance in the task through repetition, however, the infants with Down syndrome had lower frequencies of kicks.
