Here is the design of a clinical trial:

Official Title: Rationale, Design and Methods of a Study on Physical Activity, Sedentarism, Physical Fitness, and Brain , Cognitive Performance and Academic Achievement in School Children. The Cogni-Action Project

Included conditions:
- Cognitive Function 1, Social

Study Armgroups:
- {'label': 'Sedentary condition', 'type': 'EXPERIMENTAL', 'interventionNames': ['Behavioral: physical activity']}
- {'label': 'Moderate-intensity continuous training', 'type': 'EXPERIMENTAL', 'interventionNames': ['Behavioral: physical activity']}
- {'label': 'Cooperative-high-intensity interval training', 'type': 'EXPERIMENTAL', 'interventionNames': ['Behavioral: physical activity']}

Interventions:
- {'type': 'BEHAVIORAL', 'name': 'physical activity', 'description': 'Participants will assist to the three different sessions at the same weekday (e.g., Monday) and at the same daytime to avoid differences in preceding school activities or circadian rhythms. Participants will undergo a "Sedentary condition" (SC), sitting and watching a documentary on TV as has been used previously, and two different PA protocols consisting in "Moderate-Intensity Continuous Training" (MICT), i.e., continuous outdoor walking, and "Cooperative High-Intensity Interval Training" (C-HIIT), composed of a circuit training with a partner (physical education teacher)', 'armGroupLabels': ['Cooperative-high-intensity interval training', 'Moderate-intensity continuous training', 'Sedentary condition']}

Primary Outcomes:
- {'measure': 'Cognitive performance', 'description': 'The Neurocognitive Performance test (NCPT, Lumos Labs, Inc.) is used to assess cognitive performance. It is a brief, repeatable, web-based platform of cognitive tasks intended to measure functioning across several cognitive domains including: working memory, visuospatial memory, psychomotor speed, fluid and logical reasoning, response inhibition, numerical calculation, and selective and divided attention. The NCPT has demonstrated adequate reliability and validity as a measure of cognitive performance, and in good concordance with pencil-paper assessments. Moreover, verb generation and working memory n-back tasks will be measured during the analysis with magnetic resonance in resting state. Also, reading and working memory n-back tasks will be measured during neuroelectric and eye-tracker measurements', 'timeFrame': 'up to eight months'}
- {'measure': 'Brain structure and function', 'description': 'Brain structural and functional information will be acquired using neuroimaging techniques. All images will be obtained with a 1.5 Tesla MRI scanner (AVANTO, Siemens Medical Systems, Erlangen, Germany).', 'timeFrame': 'up to eight months'}
- {'measure': 'Neuroelectric measurement', 'description': 'Electroencephalogram (EEG) measurement: A B-Alert X24 device for EEG (Advanced Brain Monitoring, California, United States) will be used, which consists of 24 active electrodes that minimize the noise of electrical devices outside the biological processes of interest, ensuring good signal quality.', 'timeFrame': 'up to eight months'}
- {'measure': 'Eye-tracker measurement', 'description': 'Eye-tracker: A Tobii Pro TX300 (Tobii, Stockholm, Sweden) will be used to track eye movements directly through a light sensitive camera near the infrared spectrum.', 'timeFrame': 'up to eight months'}

Please estimate the sample size based on the assumption: 
Significance level (α) < 0.05, power > 80%, and a loss rate of 20%.
Total sample size and power
            For feasibility reasons, the school chosen for the development of exercise sessions is close to our laboratory. Sample size is estimated according to the mean difference of two independent samples from a randomized controlled trial were a working memory task (2-back) was tested [56]. Children control group achieved a positive variation (ââ=â2.05âms; SDâ=â93.1) while exercise group a negative variation (ââ=âââ69.45âms; SDâ=â91.6) [56]. A loss rate of 20% was considered. Statistical power analysis indicated that at least 32 participants would yield adequate power (i.e., >â80%) and Î± (i.e.,â<â0.05), with a detectable variation of 71.50âms (â between experimental conditions â control condition).