The intervention protocol will be carried out under the same environmental conditions and, as far as possible, on time. The intervention will last 4 weeks, with a periodicity of 7 weekly sessions. In total there will be 28 sessions lasting between 15 and 45 minutes depending on the number of joints affected.

With a pressure algometer (model Wagner FPN100) we will measure the pressure pain threshold, at the joint level and at a distance (in another part of the body). This device measures in Newton / cm2 the pressure at which the subject perceives pain under pressure. A pressure will be made on the chosen point, which we will increase at an approximate speed of 50kPa / s until the patient warns us that the sensation begins to be painful. Hemophilic arthropathy will be assessed in the elbow (on the lateral epicondyle, in the C5-C6 joint and in the tibialis anterior muscle), knee (inner edge of the patella, and tibialis anterior and extensor carpi longus muscles) and ankle (lateral malleolus, L5 spinous process, and extensor carpi longus muscle).

With a pressure dynamometer (microFET®2 Digital Handheld model) we will measure the strength of the biceps brachii, quadriceps and triceps surae. This device measures in Newton the force that the patient exerts in the requested muscular action. The higher the value, the greater the muscle strength. We will carry out the measurements bilaterally. The patient will be asked 4 maximum isometric contractions of 5 seconds, with a rest of 30 seconds between them, against the dynamometer located in the hand of the evaluator

Using surface electromyography (model SHIMMMER2, Shimmer, Ireland), we will evaluate the electrical activity of the musculature and its level of activation. The placement of the electrodes will be marked on the standing subjects, and they will be placed following the European recommendations for the use of the SEMG. A bipolar SEMG system will be used with circular electrodes 10 mm in diameter, 20 mm apart, placed longitudinally, in the direction of the fibers of the studied muscle, and with a remote reference electrode.

Using the generic Short Form 12 (SF-12v2) scale, the perception of quality of life of the patients included in the study will be evaluated. This scale consists of 12 items and a range from 0 to 100 points (where a higher score indicates a better perception of quality of life).

With the State-Trait Anxiety Inventory (STAI) scale, the perception of anxiety of the patients included in the study will be measured. The state and the anxiety trait of each subject are evaluated with a score of 0 to 30 points for each scale, where a higher score indicates a higher anxiety index in the trait or state.

With the Tampa Scale of kinesiophobia (TSK-11SV) questionnaire, the fear of movement of the patients included in the study will be evaluated. It consists of 11 items. Its values have a range of 1 to 4 points, where the higher the score, the greater the fear of movement.

With the Pain catastrophizing scale questionnaire, the catastrophizing of patients with congenital coagulopathies will be measured. The scale, made up of 13 items, is assessed with a range of 0 to 4 points (lower score indicates less catastrophism).

With the Hemophilia Joint Health Score scale, specific for its use in patients with hemophilia, the joint status of patients with hemophilic arthropathy will be evaluated. It evaluates 8 items: inflammation and duration of this, pain, muscle atrophy and strength, crackles, and loss of flexion and extension. It has a score of 0 (no joint damage) to 20 points (maximum joint damage) per joint (elbows, knees and ankles). A gait rating is added to the 120 points (range 0-4 points), the maximum rating on this scale being 124 points.