A new website is warning women of the dangers of over-exercise and restricted diets that can result in bone mineral loss, eating problems and menstruation difficulties.
University of Waikato senior lecturer Holly Thorpe co-designed the fuelaotearoa.co.nz website with AUT PhD candidate Maria Bentley.
She said it was designed to help women gain a better understanding of the role of energy balance and exercise, while promoting health and wellbeing.
Dr Thorpe said the issue was a complex one for female athletes and exercising women.
"It is not as simple as over-exercising or disordered eating. There are many social, psychological and physiological aspects that contribute to this health issue, and our website attempts to illustrate these complexities without overwhelming readers.
"The website is not intended to be alarmist; rather it aims to empower girls and women to experience the numerous benefits associated with exercise and high-performance sport while avoiding the negative consequences of energy deficiency."
Ms Bentley said the website aimed to debunk some of the myths and stigmas surrounding the "female athlete triad" (energy availability, menstrual function and bone density) and how it affects athletes and exercising women. "We want to provide accessible research-based information to improve awareness and understanding for athletic girls and women as well as parents, coaches and health professionals.
"We are not telling women to exercise less. This is absolutely the wrong message. We are encouraging them to educate themselves about how their bodies respond to the demands of exercise and the importance of nutrition to fuel their training without compromising long-term health of bones and the reproductive and cardiovascular systems."
Dr Thorpe and Ms Bentley are hoping to follow up on the website by providing educational seminars to groups of female athletes, exercising women and coaches.
Reproductive endocrinologist Stella Milsom said the website highlighted a problem that's not just confined to elite athletes.
She said there were increasing numbers of women of reproductive age suffering from a hormone deficiency syndrome known as hypothalamic amenorrhea - when the body does not produce enough oestrogen.
This was happening more frequently among career-driven women in high-stress environments but also teenage girls and young female university students, who focused on the type and quantities of food that they ate and had an "excessive" focus on fitness and body aesthetics.
"Someone becomes over-exercised so there is an energy deficit between what they are using up and what they are taking in, associated with a lot of work and stress, and basically the body says, 'Enough is enough, this woman is not healthy enough to get pregnant', Dr Milsom said.
"The issue is not just having periods ... What it means is lack of fertility, but most importantly you do not have enough oestrogen circulating, which is essential when you're laying down bone in your teens and is also essential for heart health.
"They may as well be menopausal because their fracture risk is increased and their fertility is diminished."
What is the female athlete triad?
It is a term coined by the American College of Sports Medicine to illustrate the three separate conditions of bone mineral loss, disordered eating, and amenorrhea - when the body does not produce enough oestrogen.
What is low energy availability?
Energy availability describes the dietary energy that is available to perform all other physiological functions after accounting for the energy expended during exercise.
What happens when the female athlete triad and low energy availability combine?
There can be serious implications for reproductive and bone health as well as impaired cardiovascular function, mood and sport performance.