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

Abstract

The index finger and the 4th finger ratio (2D:4D) is the indicator of the prenatal testosterone. The aim of this study is to investigate the relationship between 2D:4D, hand preference and hand grip strength in swimmers. A total of 80 elite swimmers, participated in the study. Height, body weight, body mass index (BMI), hand 2D:4D finger measurements and hand grip strength tests were performed for athletes. The hand preference was determined by the Oldfield questionnaire and it was evaluated according to the Geschwind score. The data were recorded in the SPSS 20 program and p<0.05 was considered as statistically significant. It was found that in both men and women, a negative correlation was found between right and left hand 2D:4D and both dominant (DHGS) and non-dominant hand grip strength (NDHGS) values. It was found that men had lower 2D:4D ratio than women. For both right and left handed, there was a statistically significant difference between the right and left hand 2D:4D ratios in both men and women (p<0.05) and the dominant hand (DH) 2D:4D ratios were found to be lower than non-dominant hand (NDH) 2D:4D ratios in both men and women (p<0.05)  It can be said that the 2D:4D ratios may be the effect of determining the hand preference, the grip strength and therefore the strength.