The control group will be administered a standard physical therapy intervention program which will consist of active muscle stretching and aerobic exercises.

Exercises will include:

• Flexion, extension and abduction at the shoulder joint for anterior, middle and posterior fibers of deltoid
• Flexion and extension at the elbow for biceps and triceps trachii
• Flexion and extension at the knee joint for quadriceps and hamstring muscles
• Plantar flexion at the ankle joint for gastrocnemius and soleus

Three sets of ten repetitions of each exercise will be done.

The intervention group will undergo a progressive resistance training program consisting of active muscle stretching and resistance training. Exercise for intervention group will consist of:

• Resisted flexion, extension and abduction at the shoulder joint for anterior, middle and posterior deltoid, using dumbbells
• Resisted flexion and extension at the elbow for biceps and triceps trachii, using dumbbells
• Resisted flexion and extension of knee joint for quadriceps and hamstring muscles, using therabands
• Resisted dorsiflexion and plantar flexion of gastrocnemius and soleus, using therabands

Resistance will be increased on basis of progressive overload principle. Three sets of ten repetitions will be performed per muscle group. Initial weight of the dumbbells will be 1kg and will be increased by 0.5kg per week.

Resistance training of upper limb and lower limb muscles. Resistance will be increased on a weekly basis. Dumbbells and therabands will be used to provide resistance.

An objective marker to determine muscle strength. It ranges from 0-5

0 no movement of muscle

1. flickering movement of muscle
2. full range of motion in a gravity minimized position
3. full range of motion against gravity, without resistance
4. muscle can hold against moderate resistance
5. muscle can hold against maximal resistance

The HJHS measures joint health, in the domain of body structure and function (i.e. impairment), of the joints most commonly affected by bleeding in hemophilia: the knees, ankles, and elbows. It can be used when there is a need for orthopedic intervention, or as an outcome measure of physiotherapy interventions.

A scoring system is present, which combines the score of these questions, with a global gait score, to give an overall score. The greater the score, the poorer the outcome.

The HJHS 2.1 provides a total score (higher score is worse; max=124), joint specific scores, and a global gait score.

The second subjective marker. This will be used to assess the subjective workload of exercises, and to note if exercise intensity decreases over time.

The values range from 6-20, with 6 rated as 'no exertion', and 20 rated as 'maximal exertion'.

The subjective marker of this study. This measure will assess the quality of life. It is a scale specifically designed for people with hemophilia.

The HEP-Test-Q consists of 25 items pertaining to 4 domains 'mobility', 'strength & coordination', 'endurance' and 'body perception' and one single item, which assesses changes in physical functioning in comparison to the previous year.

The recall period for the assessment of physical functioning is over "the past four weeks".

The response options range on a 5-point Likert scale from "never" to "always".

Some of the items have to be re-coded. Subscales and the total score are transformed to a scale of 0-100 with high scores indicating better physical functioning.