Many studies report a beneficial effect of physical activity on chronic pain and exercise is a recognised non-medical treatment for chronic pain (Rasu et al. J Pain, 14, 568-578, 2013). However more data is needed to inform an evidence-based approach to the concept of ‘exercise as a prescription for pain’. In this preliminary study, we have utilised quantitative sensory testing (QST) and the recording of contact heat-evoked potentials (CHEPS), to evaluate the effect of a short-term exercise programme on pain perception in healthy control (HC) participants and participants self-reporting chronic lower back pain (CLBP). All protocols had local ethical approval. HC (n=4) and CLBP (n=4) participants undertook a short-term exercise programme (2 weeks; total daily steps increased by 25% relative to 1 week control baseline average). Pain perception was assessed using a QST protocol for measurement of hot pain threshold and CHEPS were recorded using a standard EEG methodology (Brain Vision, UK) in response to thermal stimuli (49-51oC) applied to the distal volar forearm surface (Pathway System, MEDOC, Israel). A 1-10 numerical rating scale (NRS) was used to report subjective pain intensity. Subjects were tested in week 1 prior to the exercise regime and again in week 3 after completion of the exercise programme. Values are means ± S.E.M. and paired Student’s t-tests used for statistical analyses. For HC subjects, the amplitudes of CHEPS elicited by painful thermal stimuli (49 – 51oC) in the post-exercise period (16.70 ± 1.85 μV), were significantly lower compared to pre-exercise values (19.94 ± 2.47 μV; P<0.05). A similar effect was observed in the CLBP group with post-exercise CHEPS amplitude values (21.35 ± 3.16 μV) significantly lower than pre-exercise baseline values (25.16 ± 2.79 μV; P<0.05). For the HC group, reported pain rating NRS values for 49-51oC were reduced; HC group pre-exercise values were 7.13 ± 0.48 compared to 5.13 ± 0.83 post-exercise (P<0.05). For the CLBP group, the corresponding NRS values were 5.88 ± 0.44 vs 5.00 ± 0.46 (n.s.). For HC subjects post-exercise, there was a significant increase in the hot pain threshold temperature (from 46.87 ± 1.65 to 49.56 ± 0.97°C, P<0.05). For CLBP subjects, pre- and post-exercise pain thresholds for nociceptive heat were unchanged (respective values of 45.10 ± 5.99 versus 45.47 ± 6.38°C, n.s.). Overall, these preliminary data support the view that short-duration, low intensity physical activity can modify an individual’s pain experience, as measured by QST and CHEPS, but extended studies are required to determine if such regimes may be beneficial to those with musculo-skeletal chronic pain.