Blair T Crewther1, Christian J Cook2. 1. Institute of Sport - National Research Institute, Warsaw, Poland; Hamlyn Centre for Robotic Surgery, Imperial College, UK. Electronic address: blair.crewther@gmail.com. 2. Hamlyn Centre for Robotic Surgery, Imperial College, UK; University of Canberra Research Institute for Sport and Exercise, Canberra University, Canberra, Australia; Sport and Exercise, Bangor University, Bangor, UK.
Abstract
BACKGROUND: There is evidence linking women's testosterone (T) to competitive behaviours in sport and exercise. To advance this work, we examined the longitudinal relationships between salivary T (sal-T) and competitiveness in athletic women who differ in training status. METHODS: Elite (n = 9) and non-elite (n = 21) women athletes were monitored on days 6-8 (follicular phase), 13-15 (ovulatory phase) and 20-22 (Luteal phase) of a menstrual cycle with two repeats. Salivary T levels were assessed before breakfast, followed by two questions (each rated on a 1-7 scale) on competitive desire and training motivation. Using a linear mixed model, we evaluated the menstrual phase and training status effects on each variable, before assessing the within-subject effects of sal-T on competitiveness. RESULTS: Salivary T concentrations were higher at ovulation (effect size [ES] difference = 0.2-1.4), relative to the follicular and luteal phases, with a more marked response among elite women (p < .01). The competitiveness ratings showed similar menstrual-phase variation (ES difference = 0.6-1.0 at ovulation). A positive effect of sal-T on competitiveness emerged in both groups (p < .001), but with different slope patterns (p < .015). Specifically, the elite sal-T relationships with desire to compete (standardized β = 1.147, SE = 0.132) and training motivation (β = 1.195, SE = 0.124) were stronger compared with non-elite women (β = 0.631, SE = 0.114; β = 0.778, SE = 0.114), respectively. CONCLUSIONS: Morning sal-T concentrations, competitive desire and training motivation all peaked around ovulation in women athletes. Notably, sal-T availability and its relationship with competitiveness was stronger among high-performing athletes. Our findings confirm menstrual fluctuations in T and competitiveness among naturally-cycling women, with population context as a moderating factor.
BACKGROUND: There is evidence linking women's testosterone (T) to competitive behaviours in sport and exercise. To advance this work, we examined the longitudinal relationships between salivary T (sal-T) and competitiveness in athletic women who differ in training status. METHODS: Elite (n = 9) and non-elite (n = 21) women athletes were monitored on days 6-8 (follicular phase), 13-15 (ovulatory phase) and 20-22 (Luteal phase) of a menstrual cycle with two repeats. Salivary T levels were assessed before breakfast, followed by two questions (each rated on a 1-7 scale) on competitive desire and training motivation. Using a linear mixed model, we evaluated the menstrual phase and training status effects on each variable, before assessing the within-subject effects of sal-T on competitiveness. RESULTS: Salivary T concentrations were higher at ovulation (effect size [ES] difference = 0.2-1.4), relative to the follicular and luteal phases, with a more marked response among elite women (p < .01). The competitiveness ratings showed similar menstrual-phase variation (ES difference = 0.6-1.0 at ovulation). A positive effect of sal-T on competitiveness emerged in both groups (p < .001), but with different slope patterns (p < .015). Specifically, the elite sal-T relationships with desire to compete (standardized β = 1.147, SE = 0.132) and training motivation (β = 1.195, SE = 0.124) were stronger compared with non-elite women (β = 0.631, SE = 0.114; β = 0.778, SE = 0.114), respectively. CONCLUSIONS: Morning sal-T concentrations, competitive desire and training motivation all peaked around ovulation in women athletes. Notably, sal-T availability and its relationship with competitiveness was stronger among high-performing athletes. Our findings confirm menstrual fluctuations in T and competitiveness among naturally-cycling women, with population context as a moderating factor.