Box and whiskers plots indicate median (thick line), 25-75th confidence intervals (boxed interval), range (line) and outliers (circles). Sample sizes for each category are: 0 days per week (n= 63) , <1 day per week (n = 45), ≥1 day per week: (n = 16). PPT = pain pressure threshold, CPM = conditioned pain modulation, VAS = visual analog scale, N = Newtons, NRS = numerical rating scale.