Watch your back
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 recognize those situations where your back is most a risk: bending, lifting, reaching, twisting, etc. Then take measures to avoid an injury.
Stretch first – 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.
Slow down – 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