Athletes on contraception could be in the slow lane

When she’s not in a Griffith University exercise physiology laboratory
studying the effects of oral contraception on endurance athletes, Sarah Joyce can be found pounding the pavements and clocking up her own kilometres.

A Tasmanian university student is making strides on the Gold Coast in more ways

than one.

“On average I would complete approximately 60 recreational kilometres per week,” 28-year-old Sarah Joyce says.

“This varies depending on study and work commitments and if I am training for any upcoming events. Running is just a hobby for me.”

Sarah, a native of Northwest Tasmania, has taken a lifelong interest in running and

athletics into her academic sphere. She has recruited 36 athletic volunteers for a PhD study into the effects of oral contraception on exercise response.

“The prevalence of oral contraception among recreational and elite female athletes

is high. It is currently estimated that as many as 80 per cent of elite female athletes

are taking oral contraception.

“Despite the high prevalence of oral contraception use among female athletes, little is known about its effect on the exercise response and athletic performance.”

Sarah followed her sister Jessica out of Tasmania to study at Griffith University and

completed an honours degree in exercise science in 2007.

A keen netball and basketball player in her youth, she started studying exercise science with a career in physiotherapy in mind but soon discovered a taste for physiology.

“I became interested in how the body’s systems, the cardiovascular, respiratory, metabolic and musculoskeletal systems, integrate to work together.”

She has taken this interest a significant step forward with her choice of research topic

for her PhD.

“My main aim is to provide valuable information to female athletes and their coaches

on the effect of oral contraception with a view to optimising athletic performance.

“Some researchers have demonstrated reduced aerobic capacity and prolonged recovery from strenuous exercise among women using oral contraception.”

Her 18-month study will assess the effect of low dose oral contraception on body responses to exercise. Determinants of endurance performance such as aerobic capacity, anaerobic threshold and exercise economy will be explored with the help of 36 fit volunteers being pushed to the limit on a cycle ergometer.

Twelve of the recruits, aged between 18 and 35, will be women taking oral contraception, 12 will be women not taking oral contraception and 12 will be men.

“Why men? I’m hypothesising that those women taking oral contraception will respond more like males because the contraception suppresses the endogenous hormones by taking a synthetic form of estrogen and progestogen.”

Sarah says that current literature suggests that oral contraception use may have

detrimental effects on endurance performance. Most previous studies, however, have only investigated the effects of oral contraception on maximal oxygen consumption.

She plans to explore other important determinants of endurance performance such

as exercise economy and muscle damage and recovery. “My personal interest is in endurance sport. I’m enjoying my research because I’ve found the right topic for me.”

Sarah has targeted the Gold Coast Marathon in July for her next personal endurance test. It will be her third marathon, following her first 26-mile run in Washington DC in 2002

and her second in Melbourne last year. In between those outings she has also completed numerous 21km, 10km and 5km races.

“I like to participate in races as an extra challenge and to assist in motivating me to train.”