Here is the design of a clinical trial:

Official Title: Effects of Cycling Workstation on Cardiometabolic Health for Workers With an Office-sitting Desk

Included conditions:
- Sedentary Behavior

Study Armgroups:
- {'label': 'Cycling workstation', 'type': 'EXPERIMENTAL', 'description': 'Participants will have a portable pedal machine under their desk and will use it 60minutes per day (30minutes in the morning and 30minutes in the afternoon) during 6 months', 'interventionNames': ['Behavioral: cycling']}
- {'label': 'control', 'type': 'PLACEBO_COMPARATOR', 'description': 'Daily activities unchanged during 3 months. Then they will have a portable pedal machine under their desk and will use it 60minutes per day (30minutes in the morning and 30minutes in the afternoon) during 3 months.', 'interventionNames': ['Behavioral: cycling']}

Interventions:
- {'type': 'BEHAVIORAL', 'name': 'cycling', 'description': 'Participants will have a portable pedal machine under their desk and will use it 60minutes per day', 'armGroupLabels': ['Cycling workstation', 'control']}

Primary Outcomes:
- {'measure': 'effects of the use of a cycling Workstation for 60 minutes per day (30 minutes twice a day) for 3 months among professionals with an office-sitting desk on overall quantity of physical activity time (work and non-work) and sedentary time', 'description': 'Quantify by the use of an accelerometer device wears at the hip', 'timeFrame': 'month 3'}

Please estimate the sample size based on the assumption: 
Two-sided type I error at 5%, statistical power greater than 80%, and consideration of a 50% dropout rate.
Sample size and power calculation
        Sample size estimation is based on CONSORT 2010 statement for the comparison between randomized groups. In these statements, Eldridge et al. suggested âthat the size of a trial should be related to the size of the future definitive RCT and for such a trial designed with 90% power and two sided 5% significanceâ [109]. They ârecommend trial sample sizes for each treatment arm of 75, 25, 15, and 10 for standardized effect sizes that are extra small (0.1), small (0.2), medium (0.5), or large (0.8), respectivelyâ. Considering a two-sided type I error at 5% and a statistical power greater than 80%, an effect size of 1 can be assumed for the PA and SB levels score with 18 patients per group. To take into account the lost to follow-up, a maximum of 80 patients (20 by arm, 50% females) will be included in the study.