Digit ratio (2D:4D) and rowing ergometer performance in males and females

Abstract

Fetal and adult testosterone may be vital in the establishment and maintenance of sex-dependent abilities associated with male physical competitiveness. It has been shown that digit ratio (2D:4D) is negatively associated with prenatal testosterone, and it is also negatively associated with ability in sports such as football, skiing, middle distance running, and endurance running, which are dependent upon an efficient cardiovascular system. The relationship between digit ratio and sports requiring high power (physical strength) output in addition to well-developed cardiovascular systems has not been defined. This study investigated this association in male and female young adult rowers. Participants (77 male and 70 female) were student rowers encompassing a range of abilities from the University of Cambridge. Bilateral digit measurements were taken blind from each subject using Mitutoyo vernier calipers. Rowing performance over 2,000 m was assessed using the Concept 2 rowing ergometer. Significant negative correlations were observed between 2,000 m ergometer performance and male digit ratios, which persisted following adjustment for rowing experience and height. However, no such significant association was found in females despite a comparable sample size. Our data indicate that digit ratio is a predictor of ability in rowing, a sport which requires both cardiovascular efficiency and high power output, in males but not females. This in turn suggests that fetal testosterone exposure has long-term effects on traits associated with physical power in males but not females, suggesting a sex-difference in the capacity to respond to such exposures.

Digit ratio (2D:4D) and salivary testosterone, oestradiol and cortisol levels under challenge: Evidence for prenatal effects on adult endocrine responses

“…A lower digit ratio (2D:4D) correlates with performance in tests of strength [2] and endurance [3], and to performance in sporting activities such as rugby, soccer, surfing, skiing and running [4]. These relationships might be linked to the negative association between 2D:4D and T/E exposure in utero.…”

The Relationship of Digit Ratio (2D:4D) With Cerebral Lateralization and Grip Strength in Elite Swimmers

“…In many studies, 2D:4D finger ratio showed a negative correlation with physical fitness (Manning, 2002;Manning and Taylor, 2001). Low 2D:4D ratio is considered to be associated with high performance levels in many sports branches (Manning and Taylor, 2001;Manning, 2002;Paul et al 2006;Bennett et al 2010;Longman et al 2011). Sports performance depends on both an advanced cardiovascular system and muscle strength.…”

Fluctuating Asymmetry as a Predictor for Rowing Ergometer Performance

“…The magnitude of the variance in 2 000 m performance being explained by fl uctuating asymmetry (9.5 % and 14.2 % in males and females, respectively) and the signifi cant improvement of 2 000 m performance associated with a standard deviation decrease of fl uctuating asymmetry (7.3 s and 10.2 s for males and females, respectively) suggests a potential use for fl uctuating asymmetry measurement as part of the talent identifi cation programs run by various national sporting bodies. When used in conjunction with measurements of digit ratio [7] the predictive power is further increased. This study has therefore shown that FA, when controlled for body size and diff erent levels of experience, is signifi cantly and negatively correlated with levels of attainment in a discipline requiring signifi cant energetic contributions from both aerobic and anaerobic systems.…”

“…Regression analysis, controlling for body size (height) and experience, revealed that for every standard deviation increase in fl uctuating asymmetry the 2 000 m time increased by 7.3 s, with 9.5 % of variance in ergometer performance being explained by fl uctuating asymmetry (r-squared = 0.095, p < 0.01). When right hand digit ratio data is incorporated [7] alongside fl uctuating asymmetry, height and years rowed, it is revealed that 51.5 % of variance in 2 000 m time can be explained by these factors (r-squared = 0.515). Colinearity has been tested for and no signifi cant relationships were found.…”

“…Digit ratio will also be considered through reference to earlier work [7] . The ratio of second to fourth digit ratio has been shown to vary with prenatal androgen exposure, which is in turn correlated to performance in various sports including rowing.…”