Fertility and fitness: finding the right exercise balance

By Carole Gilling-Smith, CEO and Medical Director of The Agora Clinic.

The recent revelations from Olympic cyclist Dame Laura Kenny regarding her fertility challenges have ignited a crucial discussion about the effects of elite sports on reproductive health. Dame Laura conceived her first child easily but shortly after competing in the 2021 Olympics, she had a miscarriage and a few months later she suffered from an ectopic pregnancy. In the wake of this media interest, I was asked to comment on the impact of elite sports training on fertility in an interview with BBC Radio. This has prompted me to share some of my thoughts on fitness and fertility in my first Sussex Business Times article of the year to coincide with the usual January drive to shed a few pounds through increased exercise!

The impact of elite sport training on women’s fertility

Dame Laura’s story highlights the lack of good studies and information on the relationship between the physical demands of elite sports and reproductive health. Women engaged in rigorous training regimens, such as cycling or long-distance running, often experience a significantly low body fat to muscle ratio and in a calorie deficit (when the energy demands of training are not met by adequate nutritional intake). This is not merely a side effect of their training; it can lead to hormonal disturbances that impact the menstrual cycle and the regularity of ovulation.

As a woman’s body fat percentage drops below a critical level (often associated with a body mass index below 19 kg/m2), it can trigger a cascade of hormonal changes starting at the higher levels in the brain, which disrupts the hormone signals to the ovary. This can lead to irregular periods or even amenorrhea (the absence of menstruation). This can directly affect fertility by disrupting the regular release of eggs each month. Additionally, the stress associated with competitive training can exacerbate these hormonal issues. The psychological strain results in increased cortisol levels, which can further disrupt the delicate balance of reproductive hormones.

Another critical aspect of this hormonal imbalance is the role of progesterone, a hormone essential for maintaining a pregnancy after ovulation. If progesterone levels are suboptimal, which occurs when the time between ovulation and menstruation is shorter than 14 days, the risk of miscarriage if pregnancy does occur can increase, making the journey to motherhood even more challenging for elite female athletes.

The impact of elite sport training on men’s fertility health

Male athletes, in particular cyclists, have also been found to be impacted by their training regimens. Numerous studies have indicated that intense physical activity may lead to decreased sperm count, reduced sperm motility and increased DNA damage (fragmentation) in sperm. These factors can significantly hinder a man’s fertility potential and high DNA damage in sperm is associated with an increased risk of miscarriage.

Men may also experience hormonal fluctuations due to the stresses and demands of elite training. Lower testosterone levels can negatively affect libido and sperm production, further complicating the journey to parenthood.

Optimal exercise levels for couples trying to conceive

Most of us do not train to the same level as elite athletes. But if you are trying to conceive, could exercise have a negative impact? The secret is finding the right balance, and approaching exercise mindfully, ensuring it supports rather than undermines fertility. Here are my top tips:

1. Aim for balance: In both men and women, moderate exercise has been shown in numerous studies to improve fertility outcomes especially if accompanied by a healthy diet and in women is encouraged during pregnancy. Activities like brisk walking, swimming, or cycling at a leisurely pace can help maintain overall health without the risks associated with excessive training.

2. Incorporate strength training: Adding strength training to your exercise routine can be beneficial for maintaining a healthy body composition and mitigating the risks that come with low body fat. In women it helps prepare the body for pregnancy and minimises the risk of joint pain and back ache which occur more frequently as the ligaments and joints relax to prepare the body for childbirth.

3. Manage stress levels: Regular exercise enhances the level of our brain’s feel-good hormones, dopamine and serotonin, which helps relieve anxiety and stress as well as reduce cortisol levels that impact weight and the menstrual cycle. Practicing mindfulness through yoga or meditation can also alleviate stress.

4. Listen to your body: Individuals trying to conceive should be attentive to their bodies. Notice if there are changes in menstrual cycles or overall health and be prepared to adjust exercise routines accordingly. In women, try to maintain a healthy body mass index of between 19 and 25.

5. Have a fertility MOT: If you have started the year with a plan to conceive, or you have been trying for a while, don’t leave it too late to have a fertility check – a simple scan of your ovaries and hormone test if you are a women, and sperm test if you are a man, followed by a Consultant Review of your results that will help put your mind at ease or alert you to any potential issues so you have time to do something about it.

Take-home thoughts

Dame Laura Kenny’s openness about her fertility challenges serves as a poignant reminder of the complex interplay between exercise, hormones and reproductive health. While physical activity is vital for overall well-being, it is essential to strike a balance, especially for those on the journey to parenthood. I recommend prioritising a holistic approach to reproductive health, recognising that mental, emotional, and physical well-being are all essential domains to address. Whether you’re someone committed to regular high intensity training or just beginning your fitness journey, achieving your fitness goals can still go hand in hand with nurturing your dreams of starting a family.

At the Agora Clinic, we support all individuals and couples on their road to parenthood. You can book a fertility health check-up (MOT) with one of our expert fertility consultants by getting in touch by phone 01273 229410 or visiting our website www.agoraclinic.co.uk. You can also sign up for one of our free open evenings at either our Brighton or Eastbourne clinic if you want to find out more about your options.