The effect of a 12 week walking intervention on markers of insulin resistance and systemic inflammation

OBJECTIVES: The purpose of the present study was to determine whether a community-based walking intervention, using pedometers, is effective in reducing systemic inflammatory markers. METHODS: Participants (age=49(8.9)) were recruited in Glasgow, United Kingdom, from August to December 2006 and were randomly assigned to a control (n=24; 6 males, no change in walking) and intervention group (n=24; 5 males gradually increasing walking by 3000 steps/day on 5 days of the week). Blood samples were collected at baseline, and after 12 weeks, and analysed for glucose, insulin, high sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), soluble IL-6 receptor (sIL-6R), tumour necrosis factor-alpha (TNF-alpha) and soluble TNF receptors I and II (sTNFR1 and sTNFRII). RESULTS: In the control group baseline step counts were 6356 (2953) steps/day and did not change (P>0.05) after 12 weeks, 6709 (2918) steps/day. The intervention group increased (P<0.001) step count from 6682 (3761) steps/day at baseline to 10182 (4081) steps/day at 12 weeks. Over the 12 week period there was no change in any other variables measured, in either control or intervention group. CONCLUSION: We conclude that the current community-based intervention did not affect systemic markers of inflammation or insulin sensitivity.