Preventing lower back problems sounds great in theory but its probably not always possible.
Just like a common cold or upset stomach most back problems are an unpleasant fact of life.
Rather than focusing only on physical factors such as your posture or how you sit, it is usually more useful to address factors beneficial to your general health such as; getting good sleep, managing stress, stopping smoking and perhaps, most importantly, being physically active.
Physical activity is important for everyone. In general, the more time spent being physically active, the greater the health benefits. Physical activity is associated with living longer and a reduced likelihood of developing long-lasting pain (including low back pain), diabetes, heart disease and cancer.
For good physical and mental health aim to be physically active every day. Any activity is better than none. Examples of activities include heavy gardening, carrying heavy bags, running, brisk walking or resistance training such as weight training.
The current government physical activity guidelines suggest aiming for 150 minutes of moderate intensity exercise (2 ½ hours) or 75 minutes of vigorous intensity exercise per week for increased health benefits. But, like any activity, it can be sensible to build up slowly, be realistic, and chose activities that you enjoy.