Authors’ contributions
RECRUITMENT
RF and MB conceived and designed the study. RF and MB designed the experiments and performed the sample size analysis. CB, MB, RF, and CL designed the online tool and the exercise components. RT organized and planned the blood sample analysis. UT, AS, PH, JUS, BA, JW, UB, FL, and IG gave advice on the implementation of the study design at the study sites and are involved in recruitment and data acquisition. RF, JV, JL, and CB analyzed and interpreted the data. RF wrote the original draft. All authors substantively revised the work for important intellectual content and have read and approved the submitted manuscript.