Exercise sits at the centre of AS management, and a flare is precisely when it is hardest to do. The realistic question is rarely "train or rest?" but "what version of movement fits today?" — and how to make that decision without guilt in either direction.
What the guidance actually says
NICE recommends that people with axial spondyloarthritis are referred to a specialist physiotherapist for a structured exercise programme (NICE NG65). NASS’s exercise guidance lists range of movement, posture, flexibility and a reduction in stiffness and pain among the aims, and says any exercise needs to be regular, consistent and kept up over the long term (NASS, Exercise); its safety page notes that many people have pain and stiffness in the mornings and may prefer to exercise later in the day (NASS, Safety first).
On flares specifically, NASS’s safety guidance is that there will be good and bad days where you can do a bit more or need to do a little less, that many people prefer to avoid high-impact sport during a flare, that anyone doing high-impact exercise should monitor symptoms and be open to modifying it if it sets off a flare, and to check with a health professional before starting a new programme (NASS, Safety first). The guidance is not "push through" and it is not "stop everything". It is "adapt, and ask".
What adapting looks like in practice
These are ways people commonly scale movement during a flare. None of them is a prescription; which ones suit you is a conversation with your physiotherapist.
| Instead of | People often try | Why |
|---|---|---|
| A full strength session | A shorter mobility session, or the warm-up only | Keeps the habit and the range of movement without loading a spine that is already sore |
| Training first thing | Moving later in the day | NASS notes that many people have pain and stiffness in the mornings and may prefer to exercise later in the day |
| Land-based cardio | Walking, or water-based exercise if available | Water supports the joints while allowing movement; NASS describes hydrotherapy for axial SpA |
| Loaded spinal movement | Unloaded range-of-motion work | Aims to keep the spine moving with less load while a flare settles — discuss specifics with your physiotherapist |
| Nothing at all | Five minutes of gentle movement | The NHS describes AS pain and stiffness as tending to ease with movement rather than rest; a minimum version keeps the habit going |
The common thread is that a lighter version of the day is a legitimate version of the day. This is the idea adaptive training in HAVYT is built on: a mobility session counts, and scaling a session down is a normal option rather than a failure.
When to stop and ask
- Pain that is sharp, new, or in a new place rather than your usual flare pattern.
- Symptoms that get clearly worse during or after the session and stay worse.
- Numbness, weakness, or changes in bladder or bowel control — these need urgent medical attention, not an exercise decision.
- Eye pain or redness, which NICE says should be assessed the same day (NICE NG65).
Recording it
The value of tracking here is seeing the training decisions and the flare on the same timeline. Record what you actually did — "mobility, 15 min, scaled down" — next to the daily stiffness and pain, and mark the flare’s start and end. After a few flares you can look back and see how the ones where you kept moving gently compared with the ones where you stopped entirely, in your own record. That is an observation to bring to your team, not a conclusion to act on alone.