Differences in career longevity before and after implementation of the Women's Tennis Association Tour Age Eligibility Rule and Player Development Programmes: a 25-year study

OBJECTIVES

To assess differences in career longevity, as a potential marker of athlete well-being, before and after the 1995 implementation of the Women's Tennis Association (WTA) Age Eligibility Rule (AER) and Player Development Programmes (PDP), which focused on organisational, physical and psychosocial education, skill building and support for adolescent athletes (≤17 years).

METHODS

Career longevity data were collected through 2019 on adolescent players who began professional tournament play between 1970 and 2014 and reached a WTA singles ranking of 1-150 for a minimum of 1 week during their careers. Players were separated into pre-AER/PDP and post-AER/PDP groups, consisting of those who played their first professional events (FPE) before or after 1 January 1995. Measures of career longevity included career duration and premature retirement.

RESULTS

Eight-hundred and eleven players were included in this study (51% pre-AER/PDP). The median career duration was 14.2 years for the post-AER/PDP group compared with 12.1 years for the pre-AER/PDP group (p<0.001). Moreover, post-AER/PDP players had higher probabilities of 10-year and 15-year careers compared with pre-AER/PDP players. After adjusting for age at FPE, athletes in the pre-AER/PDP group had an increased risk of shorter career duration (HR 1.55; 95% CI 1.31 to 1.83) and increased odds of premature retirement (OR 5.39; 95% CI 2.28 to 12.75) than athletes in the post-AER/PDP group.

CONCLUSIONS

Adolescent athletes participating on the WTA after the combined AER/PDP initiative had longer career durations, higher probabilities of 10-year and 15-year careers, and decreased risk of premature retirement compared with those participating prior to AER/PDP. Organisational practices that encompass both education and competition regulation can positively affect career longevity related to improving athlete well-being.

Impact of fine mesh sieve primary treatment on nitrogen removal in moving bed biofilm reactors

The purpose of this project was to investigate the effect of selective particle removal during primary treatment on nitrogen removal in moving bed biofilm reactors (MBBRs). Two small MBBR pilot plants were operated in parallel, where one train treated 2 mm screened municipal wastewater and the other train treated wastewater that had passed through a Salsnes Filter SF1000 rotating belt sieve (RBS) with a 33 µs sieve cloth. The SF1000 was operated without a filter mat on the belt. The tests confirmed that, for the wastewater characteristics at the test plant, Salsnes Filter primary treatment with a 33 µs RBS and no filter mat produced a primary effluent that was close to optimum. Removal of organic matter with the 33 µs sieve had no negative effect on the denitrification process. Nitrification rates improved by 10-15% in the train with 33 µs RBS primary treatment. Mass balance calculations showed that without RBS primary treatment, the oxygen demand in the biological system was 36% higher. Other studies have shown that the sludge produced by RBS primary treatment is beneficial for biogas production and will also significantly improve sludge dewatering of the combined primary and biological sludge.

The Sony Ericsson WTA Tour 10 year age eligibility and professional development review

Concerns have long existed over the participation of adolescent athletes in professional sports. In 2004, the Sony Ericsson WTA Tour (WTA Tour) commissioned a Professional Development Advisory Panel (PDAP) to evaluate the WTA Tour's age eligibility rule (AER) and professional development programmes (PDPs) for female tennis players since their inception in 1995. More than 75% of the 628 respondents supported the principles of the AER, and 90% indicated a need for PDPs. Statistical analysis of WTA Tour players' careers found that premature retirements (players leaving the Tour at or before age 21) decreased significantly from 7% before the AER to less than 1% afterward, and median career length increased by 43%. The PDAP recommends that the WTA Tour continues a phased-in, developmentally appropriate AER, enhances the PDPs, and works with other sport governing bodies to coordinate rules and programmes at earlier ages to aid the transition of adolescents into adult sports.

American College of Sports Medicine position stand. The Female Athlete Triad

The Female Athlete Triad is a syndrome occurring in physically active girls and women. Its interrelated components are disordered eating, amenorrhea, and osteoporosis. Pressure placed on young women to achieve or maintain unrealistically low body weight underlies development of the Triad. Adolescents and women training in sports in which low body weight is emphasized for athletic activity or appearance are at greatest risk. Girls and women with one component of the Triad should be screened for the others. Alone or in combination, Female Athlete Triad disorders can decrease physical performance and cause morbidity and mortality. More research is needed on its causes, prevalence, treatment, and consequences. All individuals working with physically active girls and women should be educated about the Female Athlete Triad and develop plans to prevent, recognize, treat, and reduce its risks.

Exercise-associated amenorrhea

Currently, more is unknown than is known about the complex interactions of exercise and the female reproductive system. Three types of menstrual changes are observed in athletes: luteal phase deficiency, anovulation, and exercise-associated amenorrhea. This article presents a clinically oriented update on the hypothesized causes, evaluation, and management of menstrual changes in active women.

Tibial Pain in an Amenorrheic Runner

A group of experts met to discuss a case from the University of California, Los Angeles, School of Medicine. This case conference is part of a series featuring a variety of sports medicine topics.

Epinephrine-induced alterations in urinary cyclic AMP in hyper- and hypothyroidism

Although ratios of urinary cyclic AMP (cAMP) to creatinine were found in this study to be elevated in hyperthyroidism, as previously reported, this elevation appears to result primarily from a decrease in the rate of urinary creatinine excretion associated with the hyperthyroid state and not to be due to an increase in the urinary cAMP production rate. Indeed, there was no significant alteration observed in the urinary cAMP excretion found in 15 hyper-, 12 eu-, and 5 hypothyroid subjects. However, a slight, but significant increase in the 24-hour urinary cAMP excretion was noted in ambulating hyperthyroid subjects (8.5 +/- 2.4 muMol/day; normal 5.2 +/- 1.6 muMol/day; P less than .05). In contrast, the effect of the infusion of 0.05 mug/kg/min of epinephrine over a 2-hour period, resulted in a significantly greater rise in urinary cAMP excretion in hyperthyroid patients (0.83 +/- 0.07 muMol/h) compared to euthyroid subjects (0.53 +/- 0.4 muMol/h; P less than .005). Furthermore, hypothyroid subjects had no significant rise in urinary cAMP excretion after epinephrine infusion (P less than .001). Cardiovascular end-organ response to the epinephrine infusion was also greater in the hyperthyroid subjects and virtually absent in the hypothyroid group. These results suggest that there may be a significant alteration in the cAMP generating systems in states of thyroid hormone excess or insufficiency, and that provocative stimuli, such as epinephrine, may have its end-organ response modified by thyroid hormone effects on adenylate cyclase-cyclic AMP generating systems.