Testosterone and attitudes toward competition

第二指(食指)与第四指(无名指)的指长比(2D：4D)被认为是产前接触睾丸素的一个假定标志。据报道，胎儿和成人的睾酮可能对心血管系统、反应时间、攻击性和男子气概等生理和心理特征的发展至关重要。睾丸素驱动的属性与男性对男性身体竞争的成功有关，这可能是由运动能力来替代的。许多研究人员发现，2D：4D是性二态的，与运动成绩呈负相关。这项研究旨在调查2D：4D与力量测量之间的关系，这是另一种可能的与睾酮相关的特质，在相扑中使用能力来替代男性的身体竞争力。相扑成绩的衡量标准包括142名日本职业相扑运动员的相扑排名和胜率。我们发现，2D：4D低的相扑运动员相扑排名更高，获胜记录更好。2D：4D与相扑运动员的运动能力之间的显著负相关为高睾酮水平与肌肉力量之间的可能联系提供了进一步的证据。然而，这项研究中发现的相对较小的影响大小表明，2D：4D对需要爆发力的运动的预测作用可能比对耐力运动的预测弱。

The second (index finger) to fourth (ring finger) digit length ratio (2D : 4D) is known to be a putative marker of prenatal exposure to testosterone. It has been reported that fetal and adult testosterone may be critical for development of physical and mental traits such as cardiovascular system, reaction time, aggressiveness and masculinity. Testosterone-driven attributes are associated with success in male-to-male physical competition, which may be proxied by ability in sports. Many researchers have found that 2D : 4D is sexually dimorphic and is a negative correlate of athletic performance. This study aims to investigate the associations of 2D : 4D with measures of power as another possible testosterone-associated trait using ability in sumo wrestling as a proxy for male physical competitiveness. The measures of sumo performance comprised the sumo ranks and winning percentages of 142 Japanese professional sumo wrestlers. We found that sumo wrestlers with low 2D : 4D had higher sumo ranks and better winning records. The significant negative associations between 2D : 4D and the athletic prowess of sumo wrestlers provide further evidence of the possible link between high testosterone levels and muscle strength. The relatively small effect sizes found in this study, however, imply that 2D : 4D may be a weaker predictor for sports requiring explosive power than for those requiring endurance.