Hey Guys…How’s Your Libido?

To all you men out there, I have a simple question for you……. How sexually fatigued are you? Or to phrase it another way; Think back over the past month, how’s your libido been?

In a previous blog I talked about Relative Energy Deficiency in Sport (RED-S) which, in an overly simplistic explanation, is the extension of the female athlete triad. For those who haven’t heard about the triad, it is a condition that is seen in females (typically athletes) where a low food intake to energy output ratio results in the suppression of the menstrual cycle and the loss of the female reproductive hormones. The loss of these hormones is highly problematic for the athlete, especially with the reduction in oestrogen which supports fat metabolism and carbohydrate sparing, cardiovascular function and bone health. As a result of chronic low oestrogen levels there is reduced bone mineral density and an increased risk of stress fractures. Not only does it affect the reproductive hormones, but there are a whole host of other physiological systems effected and it can have a large impact on athletic performance.

Research in this space on RED-S and the female athlete triad is relatively large, but then we don’t tend to see a lot of research in ‘female athletes and exercise performance’. Guys, you usually hog this research space. Most of the performance, training and supplement studies have mostly been done in men, with less than 10% of this research being specific to females. The main reason for this is that a healthy female will have a menstrual cycle where we see fluctuations in hormones that affect metabolism, body temperature, fluid retention, cardiovascular function (to name a few), so there’s a lot more variables to control. So, scientists will often take the easy route and will choose male participants. But due to some prominent sport scientists, such as Stacy Sims and others, there is a massive turning of the tables in this space and there is a push for more ‘female athlete performance’ research.

Now don’t get me wrong, as a female athlete I love this topic and that female athlete performance is finally getting talked about but let’s not forget about you men in this specific topic. In 2014 a group of specialists got together to talk about low energy availability (LEA) and as a result, collectively, they recognised that this syndrome was not restricted to females but can present in males too! Now although you men dominate the performance research space, the topic of RED-S and the impact for men is an area that is lacking. So, let’s talk.

As an athlete, I train a lot with guys. I swim with them, I ride with them and I run with them. In fact, I train more with guys than I do girls. This has opened many discussions for me to talk about men’s physiological health and how to maintain this. RED-S in men is not too different to the RED-S we see in females; the underlying cause is the same. There is a mismatch between energy from food consumed and the energy that the body needs to complete exercise and maintain normal physiological functioning. Male athletes are typically perceived as being far more robust than females and, therefore, able to sustain larger training loads and volumes. With large training loads without increased food intake or well managed nutritional intake, this can result in large blocks of time in a state of low energy availability. There may also be cyclical changes in weight from training to competition that may create disordered eating behaviours or an unintentional prolonged period within low energy availability to get down to body weight (or race weight). While there is minimal research in this space, there is evidence that the male athletes that are most at risk are those involved in cycling, rowing, running, horse racing and weight class combat sports.

While RED-S is acknowledged as occurring in males, the exact physiological responses specific to males and the threshold and duration of low energy availability to cause these symptoms is still unknown. Talk about biased. How do we have so much research on performance and sweet nothing in health?! But let’s focus on the small amount of research which we do have for men in this space. Like the female athlete triad, men in a chronic state of low energy availability (whether intentional or not) may present with similar symptoms, now coined the male athlete triad. Yes, a male triad with disordered reproductive function and declines in bone health. Like females, the male reproductive system does appear to be sensitive to the stress of exercise and training, with well-trained endurance males typically presenting with 60-80% lower baseline testosterone levels compared to age-matched sedentary men. Research that has taken healthy males and trained them for 6 months has shown a decline in testosterone ranging from 20-40% even though this research was not done with the additional stress of an energy deficit or in a state of low energy availability. In instances where we have large training loads and inadequate nutritional intake, we may see exaggerated declines in testosterone (or exercise induced hypogonadal (EIH) syndrome). With EIH, male athletes will present with low testosterone levels, sometimes in the sub clinical ranges and sometimes at the very lower end of the normal cut off for men. In some cases of EIH, lower pulses of a hormone known as luteinizing hormone, that stimulates testosterone formation in the testes is reported and/or reduction in a hormone known as prolactin. These research findings would indicate that in EIH there is a disruption in the brain-gonad axis just like in the female athlete triad.

What effect does lower testosterone have on male health? Testosterone is probably most well-known for its anabolic (muscle building) effects and support of muscle growth, maintenance and neuromuscular adaptations. With adequate testosterone levels there will typically be improved size and performance of the skeletal muscles (those that contract during exercise). Testosterone also blunts the hormone hepcidin (controls iron movement and absorption in the body), meaning that there is a lower risk of iron deficiency and adequate delivery of iron to the bone marrow for the formation of red blood cells. As an endurance athlete we should be aiming to maintain a healthy hormonal profile through a well-structured training programme that provides recovery from the stress of exercise along with adequate nutrition. This will enable maintenance of normal physiological processes like protein turnover, digestion, red blood cell production and cardiovascular function. There are several compelling studies in males with EIH that have also demonstrated reduced bone mineral density, proposed to be a result of the changes to male anabolic hormones. Let me put it this way, guys if you have a stress fracture or have had more than two in your sporting life, then we seriously need to have a talk about your training, nutrition and physiology! Other areas that are affected by EIH include reduced sperm development, [SL1] with some research showing reduced sperm density, motility and an increase in abnormal morphology of sperm.

Unlike females that will have a physical sign when they enter the spectrum of RED-S (i.e. the lose of a period), when a man presents with EIH, possibly an indicator of RED-S and male triad, there is a common belief that you will not be able to detect this until the inevitable stress fracture or burnout/overtraining occurs. But what if we used libido as an indicator?

Does this scenario sound familiar…. Guy commits to endurance event and starts training, loves the training and starts to see the fitness gains. Partner is highly supportive. Months go by and race day draws nearer, and people start throwing around jokes of endurance sports being a recipe for ending a romantic relationship. You may hear a guy say he is just tired from training and stressed from work and just not feeling it lately. His partner will probably be telling you about how things are a bit stressed or strained between them. Race day comes, guy races, then follows the post-race recovery period with lots of rest and food. Now ask that partner how they are feeling 1-2 weeks after race day and home life is suddenly great again. Let’s explain this with some physiology, the guy starts training and consistent training reduces testosterone levels, albeit quite marginally at first. Training ramps up and nutrition doesn’t change or increase to compensate for increased exercise demand, and the result is a prolonged period of low energy availability in the lead up to race day. Guy physiologically enters EIH and is tired, stressed, doesn’t feel as recovered from training (but puts this down to poor sleep, work life and increase training load). He makes it to race day, does his best and then afterwards has a break from exercise and as a result the food he is eating is enough to support his normal physiological functioning and the minimal exercise he is doing. Getting the balance right reverses the fatigue, stress and other subjective feelings he was presenting with in the lead up to race day.

Research has suggested that in men with EIH a very common subjective response is a reduction in libido. Combine exercise, high workplace stress and lack of sleep, you may achieve the perfect storm for reduced libido in men. In fact, it is very well recognised that in RED-S the psychological impact on the physiology is bio-directional, meaning that high stress from work and high exercise loads and low energy availability are probably all affecting and exaggerating one another.

This is a simple presentation of a very complex process which is often not as straight forward as this, but let’s initiate this conversation before a male athlete reaches the state of burnout and over-training. As confronting as this may be to start talking about, this is something that will benefit your health and performance in the long term as an athlete and we need to break down any stigma attached to this conversation.

So, here are my take home messages;

·        men can present with RED-S that can affect numerous areas of their physiology that will then affect their health and exercise performance.

·        Key areas affected are iron regulation, bone health and reproductive function.

·        While men may not have a physical symptom for RED-S they tend to have a very strong subjective response. One that is not only noted by them but may be noted by their partner or significant other.

·        If you are a guy and you are training regularly, especially in the endurance space, then ask yourself this: In the last month have I been sexually fatigued, or have I noticed a change in my libido?

If you cannot associate this change with an increase in work or other life stressors and it has been low for a month or more, then it may be worth having a chat with your coach, physiologist or nutritionist about how you can adjust you training to have a recovery period or increase your food intake to help support you during your training.

Every clinic needs a doctor, at Sports Lab, Claire is ours. Dr Claire Badenhorst is our physiologist (PhD Exercise Physiology, Academic at Massey University in Auckland) with research focus areas currently in female health, iron deficiency and endurance athletes.