With so much physical exertion needed to thoroughly clean a house, it’s important to know your body’s limitations, and be aware of your body position at all times. Learn to recognise those situations where your back is most a risk: bending, lifting, reaching, twisting, etc. Then take measures to avoid an injury.
If you know that you’re going to be doing work that might be hard on your back, take the time to stretch your muscles before starting, just like a professional athlete would do before a workout. This will help you avoid painful strains and sprains.
If you’re doing a lot of heavy, repetitive lifting, take it slowly if you can. Allow yourself more recovery time between lifts, as well. Don’t overdo it.
Rest your back
Take frequent, short (micro) breaks. Stretch. If you’ve ever been working in an awkward position for a long time, then stood up and felt stiff and sore, you know you’ve been in that position too long, and your body is now protesting. Taking a one minute stretch break every now and then can help you avoid that.
Sleep on a firm mattress
Also, the best sleeping position for many people is either on the back with the knees slightly elevated (by a pillow), or on the side with knees slightly bent.
Get in shape
Strengthen your stomach muscles, lose a little weight, increase your flexibility.
Reference: EHS Safety Training, Back Safety