After over 30 years in the NHS physiotherapy, I have found that most low back pain usually comes in 3 different presentations.
Firstly, when we are young, “acute” (new) back pain starts when we bend awkwardly or lift something heavy.
Or it can come on gradually for no reason. Usually back pain in younger ages presents as painful to bend, or sit, but better when walking. Pain is often worse when getting out of a chair with difficulty standing upright. If this pain has not spread far down the leg then then it will often respond to extension exercises. These are either extension in standing, or if these don’t help enough then extension in lying. Watch too that if sitting is sore, then you should consider sitting with some lumbar support. A firmly rolled up towel can often reduce your pain when sitting.
Extension in lying (as below ) performed throughout the day is often the exercise of choice ( pain should be getting easier as you repeat these repetitions. To know that it is working )

Secondly – some younger people (20-55) can easily bend forward, but have pain when they straighten up to standing. This can often be a presentation helped by Pilates. Pilates will build up core stability to stabilise the spine – essentially this is what is referred to as a stability problem (it is often the catching pain as we come upright again after we bend forward). Building up core strength often helps this presentation.

However as we get a little older, back pain presents very differently. From 50-60 onwards we may find that it is now walking that is most painful. And we may find that sitting eases our pain. On examination – patients can often bend forward easily to touch their toes (better than I can and I’m 55). However they struggle to bend backwards and this is often painful. This presentation is just a sign of general ageing and wear and tear.
Whilst most people this age actually have no symptoms at all, for those who do have back pain, Physiotherapy still has a lot to offer. Often this will lumbar flexion (bending) exercises, as below. The good news is that they should be comfortable to do , However to get most benefit, people find that this is likely to be at 90 repetitions a day ( 3 sets of 30 )

Also in this older age group, your Physiotherapist can advise you on specific muscle stretches and pelvic tilting exercises to reduce pain. This can often be quite successful in helping you to manage to walk further.