Effectiveness of Aerobic Exercise in Sitting Posture versus Aerobic Exercise in Standing Posture in older adults with Knee Osteoarthritis and overweight. Randomized Controlled Trial

Aerobic Exercise in Sitting Position (Experimental Group) A group of patients suffering Knee Ostearthritis (KOA) will be asked to execute 30 minutes of Aerobic Exercises seated on a chair. The intensity of the exercise is in the range of 50-70% maximal heart rate. This 30 minutes are organized as follows: *Five minutes of warm-up: In a seated position: 1 minute of hip flexo-extension to the extent possible. 1 minute of hip flexo-extension while shoulder up and down movements are executed , 1 minute of hip flexo-extension while protraction and retraction of the shoulders are performed, and 1 minute of hip flexo-extension while shoulders rolls are executed. Finally 1 minute of rest. *Twenty-five minutes of aerobic phase: Patients are asked to execute hip flexo-extension during this 25 minutes without stopping. During this time a sequence of one minute movements with the upper extremity is performed. First exercise of the sequence: 90 degrees of shoulder flexion alternating right and left arms. Second exercise: Touch the knee with the contralateral hand. Third exercise: Clap in front of him with 90 degrees for shoulder flexion. Fourth exercise, patients perform elbow flexo-extension. Fifth exercise of the sequence: consists in hugging himself. This sequence is repeated 5 times. *Five minutes of cooldown: The same exercises of the warm-up but this time in reverse order. As with the control group, fifteen minutes of inferior limb strengthening and fifteen minutes of stretching exercises (both regulated by the pain threshold of each subject) will follow this Aerobic Exercise. Strengthening will be executed in a lying position: 10 quadriceps, hamstring, adductors, abductors and sural triceps, isometric contractions, held for 10 seconds with 2 seconds of rest between each repetition, both legs. The stretching will be also performed in a lying position, as follows: 10 Quadriceps, hamstring, adductors, abductors and sural triceps elongations, held for 10 seconds with 2 seconds of rest between each repetition both legs. This program will be performed 3 times a week during 4 weeks at the “Centro de Especialidades para el Diagnostico y Tratamiento de Azuqueca de Henares” (Specialization of Diagnosis and Treatment Center of Azuqueca de Henares), every session will be led by the 2 investigators both graduated as physiotherapists and working in this project. Once the 12 supervised sessions achieved, a DVD reminder of the routines worked during previous sessions, and produced by the team of investigators will be given to each and every patient in order to enable them to continue the treatment at theirs homes 3 times a week for 8 weeks. To improve the adherence to the treatment, a self-register format is provided to the patient (a calendar in which the patient will match the days he accomplished the exercise), this paper should be returned to the team every 4 weeks.