Brief Answer:
Focus on low impact activities, such as swimming.

Detailed Answer:
Hello,
Thanks for your query.

I suggest you to try back strengthening exercises by extension of the back muscles which can be taught by your Physiotherapist.
Back strengthening exercises are as follow.

1. Lie on your back on a flat and firm surface. Grip your hands behind both of your thighs and pull them toward your chest. Hold this position for 30 seconds, then rest and repeat.

2. Kneel on flat firm surface and rest your buttocks on your heels. Lower yourself slowly and raise your arms out in front. Hold this stretch for 30 seconds and then come back to neutral position. Repeat this process favoring your left side next and then your right side. Keep rotating center, left and right.

3. Lie on your back on a flat and firm surface. Your feet should be flat, knees bent, and your legs should be together. Tilt your pelvis and push your lower back to the floor and slowly lift your buttocks off the floor as far as possible without straining. Hold this position for 5 seconds and then lower your buttocks to the floor

I would suggest you to continue swimming as this will help most in back conditions.

It is important to maintain as much activity and joint motion as possible, but it has to be kept in mind that impact activities will aggravate arthritis. Running and jumping will often accelerate cartilage loss from the joint. The key is to focus on low impact activities, such as swimming or cycling. These are the best forms of exercise with arthritic hips as they do not require significant weight bearing across the hip joints.

Avoid weight bearing exercises.

Taking calcium and vit D supplements will be helpful.

I do hope that you have found something helpful and I will be glad to answer any further query.

Take care

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