The effect of hand cooling on exercise duration: a comparison of twenty-six paired treatment trials. The effect of treatment (cooling) was affected by exercise duration during the control condition. The longer the duration of exercise in the control condition, the greater the cooling treatment effect. An exponential function (y = 12.505e0.0356x) accounted for 90% of the variance in the data. The solid line was generated by the exponential function; the dashed line represents unity. Inset: mean ± SD exercise duration with treatment and without treatment (43.6 ± 17.09 min. with treatment vs. 32.8 ± 10.9 min. without treatment (p < 5.0·10-6, two tailed paired t-test, n = 26).