Dynamics of Motivational Factors for Physical Activity and Nutrition in Oncogeriatrics

"The observational phase (during 15 days)~* Two measurements per day for motivational variables and physical activity and nutrition~* Two measurements per day for nutrition~* Three measurements per day for fatigue~* Continuous PA measurement by accelerometer~The interventional phase :~Part A (during 7 days)~* measuring physical activity (PA)~* complete questionnaires and numerical scales :~ * Motivational factors~ * Self-evaluation of nutrition~ * Self-assessment of fatigue~Part B: BEHAVIORAL INTERVENTION (10 weeks),the APA teacher will call a patient once a week for follow-up.~Answer questionnaires and scales on the digital platform will be done :~* Motivational factors~* Self-evaluation of nutrition~* Self-assessment of fatigue~Part C : End of interventional phase(during 7 days)~* measuring physical activity~* complete questionnaires and numerical scales :~ * Motivational factors~ * Self-evaluation of nutrition~ * Self-assessment of fatigue"