Can you be too fit for sex? How exercise impacts libido and bedroom performance

As an age-group athlete, it can be hard to find time for life’s certain pleasures. Most hours not dedicated to work and family are often assigned to training, and unless a night of nookie is scheduled on TrainingPeaks, it can be hard to fit extra curricular activities into your week.

But aside from one passion getting in the way of another, can the training required to be a triathlete have a deeper, physiological impact on your sex life?

“We know that exercise is hugely protective of human health, and actually can boost your energy levels,” says Dr Sarah Rollins, a sport and exercise medicine consultant at Pure Sports Medicine.

“It can improve mental health, has a positive impact on social relationships and so there is definitely this middle ground where things done in moderation and fuelled appropriately will have a positive effect on people’s sex lives and potentially their libidos.”

The science backs this up, too. A systematic review published in 2023 found that moderate aerobic exercise generally supports sexual health.

Its authors even suggested that exercise should be prescribed as a preferable alternative to medication for the enhancement of sexual functions in both men and women.

They pointed to how regular physical activity is a “crucial factor” in promoting sexual health, with the studies reviewed found exercise enhanced sexual functioning in a number of ways, including: hormonally, particularly surrounding arousal; mentally, by helping to foster a positive body image; and physiologically, by increasing blood flow to the clitoris and penis.

Other research goes even further. One study suggested that female runners who undertook ‘high effort’ sessions reported higher intensity orgasms than those who completed ‘moderate effort’ runs, with scientists pointing to better clitoral circulation and pelvic floor muscles that are functioning well.

Elsewhere, research from the University of Texas found that masters athletes who had undertaken moderate-to-vigorous exercise throughout their lives had more frequent sex, better function and higher levels of satisfaction than their non-athlete peers.

And the myth that pre-event sex is bad for performance has been truly debunked – a comprehensive review finding that abstinence can actually have a negative impact, while sex could have a positive effect on performance if it takes place between two-and-10 hours before competition.

The key factor in all of this is moderation. “Exercise is hugely health promoting and there is a healthy bit in the middle, with people at either end of the extreme probably finding it more difficult,” says Rollins.

Into the RED-S

Triathletes are prone to falling into this excessive-end of the scale, particularly if training for a long distance race like a half- or full-Ironman.

“If you’re fuelling really well but you’re just knackered because you’ve done 12-to-20 hours of endurance training in a week, it’s likely that you’re not going to be particularly excited about doing any more physical activity,” says Rollins.

“Also, you might be training at six o’clock in the morning, go to work, and then training until eight at night, so I would imagine opportunity reduces as well.”

But the training could be having more of an impact on your sex life than simply creating scheduling issues or leaving you feeling too drained to do the deed pre-bedtime.

A paper published in 2022 found that men who were conducting marathon training had lower libido scores than those who weren’t – the researchers speculating that the physical exertion of high volumes of training was directly responsible because of chronic physical fatigue, Relative Energy Deficiency in Sport (RED-S), or adaptations to the hormone-controlling endocrine glands resulting in lower testosterone.

“Endurance athletes in general are at risk of over training and hormonal imbalances, and I suspect, with the intensity of training and the volume of training, probably go through fairly frequent highs and lows of libido,” says Dr David Hulse, another sport and exercise medicine consultant at Pure Sports Medicine who is also team doctor for cycling WorldTour team EF Pro Cycling. 

Rollins agrees, and points to RED-S as a likely cause. “One of the key things that happens is that there is a mismatch between the energy expended and the calories that are taken in – we call that low energy availability. 

“Episodes of low energy availability can be sustained, if they’re intermittent and if you fuel otherwise reasonably normally on most other days, sometimes making up for the deficit.

But if you have sustained low energy availability, the body starts to go into a kind of survival mode, and change the way that it then manages its other health systems.”

Although it can impact various parts of the body – from bone health to issues with immunity – when it comes to sexual health, RED-S can affect both sexes.

The symptoms are particularly noticeable in women because the hormones in the brain that tell the ovaries to work turn off, stopping the production of estrogen and impacting the menstrual cycle.

Rollins explains that a similar process happens in men – it stops the hormones that tell the testes to work, impacting the production of testosterone – but it’s not as noticeable because of the lack of a monthly cycle.

“In the past, it was all about women – no period, bone stress injuries, but we know now that RED-S can lead to multi-system issues,” says Rollins. “Elite athletes often have access to teams that can help them.

But recreational triathletes still train really hard, and they might not necessarily get that nutritional support or advice about how to fuel, and so there’s often a mismatch between fuelling and output.”

Hulse adds that while RED-S is something that endurance athletes should be wary of, that from his experience with male professional cyclists, lower testosterone alone doesn’t automatically equate to feelings of low energy, sexual dysfunction and low libido.

“Testosterone levels in men will fluctuate with training load – they will often decrease during periods of heavy training load – and there’s quite a wide variation of what is normal across individuals.

“True testosterone deficiency is incredibly rare and there’s a common misapprehension that low testosterone levels, which are picked up on blood screens and in athletes in general, are directly related to libido and sexual function, rather than sexual dysfunction, which technically speaking they’re not.

Pressure point

Hulse believes that one of the main sexual health risks for triathletes results from the mechanics of cycling and specifically saddle pressure, which he links to genital numbness, pain, or dysfunction (both erectile dysfunction in men and female sexual dysfunction in women). 

“When we sit on bicycle saddles, we are sitting on our genitals or very near our genitals, in both men and women.

We’re also sitting on some fairly crucial nerves that run right next to our sit bones and then into the midline, called the pudendal nerve,” he says.

The nerve responsible for the sensations and control of the genitals and anus, it’s integral to sexual function and also bladder and bowel movements.

“The thing we often think about with cycling and saddle pressure is genital numbness, which is due to saddle pressure on those nerves,” he says.

“If untreated, that can become more serious and involve genital dysfunctional or erectile dysfunction, simply due to chronic injury to those nerves and other nerves within the pelvic floor.”

He adds that in women, symptoms are often pain on the vulva, rather than numbness, due to the direct pressure from the saddle, which can also lead to serious issues.

“There can be chronic injury to the lymphatic drainage of the vulva, which can then lead directly to swelling and pain, which is often very difficult to manage in itself.”

This discomfort downstairs isn’t something you simply have to put up with as a side-effect of the sport though, and Hulse points to bike fit and saddle analysis as being the best ways to alleviate any issues.

“For performance and aerodynamic reasons, we are tending nowadays to sit in a more forward flexed position – a longer, lower position. Our pelvises roll forward so that we can get into those positions, but we increase pressure on the nose of the saddle.

“The gold standard way of relieving saddle pressure is to get the bike fit right so that the person is optimally supported on the saddle, whilst being able to generate the power that they require – and there are sometimes compromises there.”

While there are an infinite variety of saddle shapes and sizes to choose from, he recommends ensuring that you’re supported through your sit bones while avoiding midline pressure. 

“Also, I would encourage any triathlete to look very seriously at triathlon-specific saddles,” he adds. Designed differently from a standard road bike saddle, they have increased pressure-relieving padding to make up for a tri suit’s lack of chamois, and large central cut-outs to relieve midline pressure.

It’s worth noting that the sexual health issues surrounding saddle pressure won’t affect all athletes, with scientific research helping to debunk the myth that riding a bike will always lead to dysfunction. 

One survey-based study found that 17% of the cyclists polled had erectile dysfunction, although its authors noted that once age was accounted for, the prevalence within the cycling community isn’t any greater than the general public. Another study showed that there was no difference between amateur cyclists and footballers.

Pelvic problems

When it comes to the disciplines of swimming and running, Rollins couldn’t see any reason why the mechanics of either sport is likely to cause any issues.

But if you supplement your endurance training with strength and conditioning work, it’s important to consider your pelvic health, and the side effects of having an under- or overactive pelvic floor.

“Generally, strength training is really positive on the pelvic floor and really important for people who are doing sport. In triathlon, you’ll run, cycle, and swim better.

“But that doesn’t necessarily mean that strength training reduces the chance of injury or improves your sex life. Doing very heavy strength work and holding on to your pelvic floor very tightly, for guys and females, can result in a hypertonic pelvic floor.”

A chronic over-tightening of the pelvic floor muscles, it can lead to symptoms like erectile dysfunction and premature ejaculation in men, and is more common in young female athletes who haven’t had children, where “it can have an impact on the comfort of having sex”.

At the other end of the scale, a weak pelvic floor can cause issues around incontinence, and is more prevalent in females who have had children.

“Running can sometimes then be really positive for those ladies to develop a stronger pelvic floor – runners might be motivated to do their pelvic floor work so that they can get back running. But it’s a bit of a balance – if you don’t do the right pelvic health work, then running can be a bit problematic.”

Rollins concludes that if you’ve never had a child but are having symptoms of tightness and pain related to intercourse, or if you’ve had a child and you’re struggling with incontinence, then it’s important to seek advice from a specialist.

Sexual cues

Triathlon alone therefore doesn’t have a negative impact on an athlete’s sexual health. Private parts remain free and unimpeded when running and swimming, and although in the firing line during cycling, the risks of saddle pressure on sexual organs can be negated with a personalised bike fit that will optimise your set-up to your anatomy.

The biggest threat to an age-grouper’s abilities in the bedroom is more down to the intensity and volume of your training plan, which can come when tackling three disciplines, although the risk of RED-S is not limited to triathlon but present with all forms of endurance exercise.

So if you’re nailing your nutrition and keeping your calories in-to-out balanced, then triathlon could actually give your bedroom-based activities a boost, with scheduling clashes and general tiredness the only thing to overcome.