Pain sensitivity and athletic performance

Purpese To determine whether higher pain thresholds are associated with better performance in long-distance runners. Design Cross-sectional study. Methods Seventy participants, divided into groups of fast and non-fast runners according to peak results in a 10km run. Main Outcome Measures, Cold pressor test. Results Of the 70 subjects, 28 were in the fastest group (less than 39 minutes in a 10km run) and 42 in the non-fast group. The faster group was characterized with older age (34.0±8.5 vs. 29.5±5.7, p=0.01), greater mean weekly running time (5.5 (0-17) vs. 2 (0- 10), p<0.001), and more years of running [10 (1.5-34.0) vs. 7 (0-20, p=0.05)]. In a multivariable analysis longer cold pressor time was associated with faster 10Km run (O.R 1.01, 95% C.I 1.00-1.01). Conclusions It seems that higher pain thresholds play an important role in the superior ability of long distance runners.


Introduction 40
After setting the world record for women in a marathon run (2:15:25) at the London 41 Marathon in 2003, a record that has not yet been broken, Paula Radcliffe was asked what 42 helped her to achieve such an impressive result. Her answer was that it was in her ability 43 to tolerate pain better and thereby break her own "boundaries" again and again 1 . 44 Pain perception is investigated using a variety of tests and questionnaires, for example the 45 cold pressor 2 test, and the MOS SF-36 questionnaire for health-related quality of life 46 assessment. 3 The association between physical training and pain perception has been 47 studied mainly by comparing trained and untrained populations. On the one hand, it 48 appears that professional physical training in endurance sports causes a change in pain 49 perception 4 On the other hand, high pain threshold and high pain resistance may lead 50 certain people to take part in this kind of physical activity. 5

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There is evidence of a link between incidence of pain, the impact of pain on 52 quality of life, and even the efficacy of treatment of pain-related situations and belonging 53 to a particular ethnic group. For example, it has been shown that an individual belonging 54 to an ethnic minority in his country is likely to have higher pain tolerance than other 55 populations in that country. Hence, it appears that there is a difference in pain perception 56 between different populations. 6 57 However, the link between runners' performance and their pain tolerance 58 threshold or their ability to tolerate pain remained unclear. We hypothesize that higher 59 pain thresholds and tolerance may lead to better performance among long-distance 60 runners and can serve as a predictor of running ability among runners. Consequently, we 61 expect that faster runners will demonstrate greater tolerance in the cold pressor test. We conducted a cross-sectional study of fast and non-fast runners. The participants were 64 divided in accordance with their best result in a 10km run. Runners with a result of 39 minutes or less on a 10km run were assigned to the fast group, while those who achieved 66 a result over 39 minutes but less than 50 minutes were assigned to the non-fast group. Each participant was asked to fill out a socio-demographic questionnaire and note 77 his running results for different distances. In order to assess pain perception and 78 threshold, we used the SF36 MOS questionnaire and the cold pressor test.

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The cold pressor test is based on neutral stimulation that activates pain receptors 80 to cold and is used to test for pain tolerance 2 . Sensitivity to cold-induced pain has been 81 proven to be related to sensitivity to mechanical pain, and high tolerance for the cold 82 pressor may be associated with inhibition of pain activation from a central source.

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Several studies have demonstrated the diagnostic ability of this test, for example documenting relatively high pain tolerance among professional dancers and relatively 85 low tolerance among patients with chronic low back pain 7 . 86 In the framework test, the subjects placed one of their arms up to the elbow into a

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Data are expressed as mean ± standard deviation (SD) and median ± inter-quartile range 93 (IQR). We compared runners' characteristics using t-test and Mann-Whitney tests. We

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Seventy subjects were found to fit the inclusion criteria (men over age 18 with a 10km 109 run result under 50 minutes) and agreed to take part in the study. Twenty-eight (28) 110 subjects were assigned to the fast group (10km in 39 minutes or less) and 42 to the non-  Table 1 presents the characteristics of the two study groups. There were a number of  We found a marginal difference of test time between the two groups, as shown in Table 1 122 (240 seconds in the fast group vs. 80 seconds in the control group, p = 0.08). It should be 123 noted that 240 seconds is the maximum test time, i.e., the median time in the fast group is 124 also the maximum time of the test. Further we performed a multivariate logistic 125 regression model while controlling for additional possible confounders associated with 126 belonging to the faster 10Km group, as shown in Table 2. After adjusting for running 127 experience (in years) and the age of the participant we found that higher cold pressor

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In this study we examined the association between pain tolerance and the performance of 132 long-distance runners based on the assumption that a higher pain threshold and greater 133 pain tolerance for longer periods may contribute to better running performance in these 134 runners. To the best of our knowledge, this assumption has not yet been examined 135 previously. Our main finding is that pain threshold and tolerance is associated with better 136 performance of long distance runners. Our results remained consistent even in 137 multivariable analysis.

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The possible reasons for the superior ability of specific groups of runners (e.g.

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Kenyan and Ethiopian runners) has created a lively focus for discussion and a number of