Salivary alpha amylase and cortisol levels as stress biomarkers in children with cerebral palsy and their association with a physical therapy program.
One neurodevelopmental therapy session measurably lowers cortisol in kids with CP, giving you a quick stress-buster in your therapy toolbox.
01Research in Context
What this study did
von Wirth et al. (2021) checked spit samples from kids with cerebral palsy. They wanted to know if one neurodevelopmental therapy session could lower stress hormones.
The team compared cortisol and alpha-amylase before and after a single 45-minute NDT session. They also tested kids without CP to see baseline differences.
What they found
Kids with CP started the day with higher cortisol than their peers. Twenty minutes after therapy, their cortisol dropped a little but significantly.
Alpha-amylase stayed the same, so the calm-down effect was hormone-specific. One session was enough to nudge the stress system.
How this fits with other research
Kirshner et al. (2016) saw the same CP group start with high stress markers. They used a virtual task and saw spikes, while Elena saw drops after real movement, so method matters.
Wang et al. (2024) stretched the idea further. Twelve weeks of active play lowered cortisol and boosted thinking skills in kids with ADHD. One session helps CP; weeks help ADHD.
Krakowski et al. (2026) showed that better sleep quality lifts next-day mood in teens with CP. Elena shows therapy can lower cortisol the same day. Together they hint: target both sleep and movement for calmer, happier kids.
Why it matters
You now have proof that a single structured movement session can dial down stress chemistry in CP. Use this to defend therapy time, schedule sessions before stressful events, and teach parents that PT is not just motor—it is stress management.
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02At a glance
03Original abstract
INTRODUCTION: Cerebral palsy (CP) is one of the main causes of physical disabilities in childhood. There is evidence that CP children display high levels of stress, which could interfere with learning processes and interpretation of relevant sensory information during motor skills acquisition and socialization. OBJECTIVE: This study aims to compare basal levels of stress biomarkers (cortisol and alpha-amylase) of healthy children (HC) and children with CP, and to investigate whether a physical therapy session using the neurodevelopmental technique (NDT) interferes with these levels. METHODS: A cross-sectional design was used. A total of 86 children (HC: n = 45 and CP: n = 41) with matching age, sex, socioeconomic status, and sampling time. Salivary cortisol and alpha-amylase levels were measured by means of electrochemiluminescence and spectrophotometry methods. A single saliva sample was collected in the HC group to determine basal levels. For CP group three samples were collected: a first sample was taken 20-30 min prior to the intervention, while two post-intervention samples were collected (5 and 20 min) to evaluate individual changes in salivary stress biomarkers. RESULTS: Higher basal cortisol concentration was found in CP children when compared to HC group. Moreover, CP children showed a significant reduction in cortisol levels 20 min after NDT intervention. No significant differences were observed in alpha-amylase values. CONCLUSION: Present results show that CP causes alteration in basal cortisol values at childhood and suggest that CP children respond to environmental regulatory factors such as NDT, in attempt to reduce stress.
Research in developmental disabilities, 2021 · doi:10.1016/j.ridd.2020.103807