|LETTER TO EDITOR
|Year : 2021 | Volume
| Issue : 1 | Page : 33-34
Low 2D: 4D may reduce the use of doping in sports
Muhammad Shahidul Islam
Office of Physical Education, Shahjalal University of Science and Technology, Sylhet, Bangladesh
|Date of Submission||22-Mar-2021|
|Date of Acceptance||03-Apr-2021|
|Date of Web Publication||07-Jun-2021|
Muhammad Shahidul Islam
Shahjalal University of Science and Technology, Sylhet
|How to cite this article:|
Islam MS. Low 2D: 4D may reduce the use of doping in sports. Saudi J Sports Med 2021;21:33-4
The length of the index finger in relation to the length of the ring finger (2D: 4D) of a palm is thought to be a potential biomarker of prenatal androgen exposure. This finger length ratio of 2D: 4D at the end of the first trimester of gestation (week 1 to week 12 of pregnancy) is also a possible pointer of prenatal testosterone and prenatal estrogen hormone balance. There-after, the prenatal hormonal balance defined by digit ratio (2D: 4D) probably remains unchanged significantly throughout life.,, On the other hand, the gender difference in digit length ratios has been linked to utero androgen to estrogen balance. The 2D: 4D is sexually dimorphic, with men's second digit (index finger) being shorter than the fourth digit (ring finger) and the length difference between the two digits being greater than women's., However, female athletes have a greater finger length difference of 2D: 4D as their ring finger becomes longer than the index finger and their digit ratio becomes low., According to early research, prenatal androgen exposure, the most significant androgen, is needed for mammalian brain sexual differentiation, which has long-term consequences for games, sports, physical activity, and competitive behavior.,,,,,,, Since the lower digit ratio (high prenatal androgens) was expected to influence the performance of soccer, surfing, sprinting, endurance, hand-grip strength, rowing, kabaddi, swimming, tennis, and other sports.,,,,,,,,,,, A fetus exposed to more testosterone is expected to have a lower digit ratio (masculine ratio). Given the fact, male fetuses are subjected to more testosterone than female fetuses and males often have lower digit ratios than females. Female elite athletes, on the other hand, have lower 2D: 4D values than female nonathletes, which is an interesting finding.,, Previous research has shown that men and women with higher, more feminized 2D: 4D ratios are more likely to suffer from depression and anxiety than those with lower, more masculine 2D: 4D ratios.
Doping agents have banned substances widely used in competitive sport, especially among female athletes, and are used by both nonelite and elite athletes to improve athletic performance. Female athletes with high or extremely high androgen levels (whether endogenous or exogenous) have a competitive advantage of 2%–5% over those with androgen levels below the standard female range in some sports. According to the study, athletes with higher serum testosterone concentrations had a competitive advantage over those with testosterone levels in the normal female range. As a result, increased endogenous androgens can boost physical performance. Therefore, a digit ratio test could be used to select female athletes, which could be an important factor in preventing doping in women's sports in the future. In the field of sports, the 2D: 4D, when combined with other physical and physiological tests, can be an important discriminator in recognizing young talent. Since a low digit ratio possibly confirms high androgen exposure in prenatal life, it may help to minimize the use of doping in sports.
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Conflicts of interest
There are no conflicts of interest.
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