 Is endurance training, like riding your bike, actively lowering your testosterone levels? And if so, what can you do about it? As I'm sure you already know, testosterone is the primary male sex hormone, although it is present in much lower amounts in females as well. However, testosterone is responsible for a lot more than just sexual function. There's a reason why supplementing with testosterone is banned by the World Antidoping Agency. And in simple, it's a performance enhancer. Testosterone promotes a higher muscle mass, a lower body fat percentage, quicker recovery, and so on. To paint a picture of just how effective testosterone is, let's turn our attention to this study on how testosterone affects muscle size and strength. Subjects were split into four groups, a placebo group that did no exercise and received no testosterone, a group that received testosterone injections but did not exercise, a group that did not receive testosterone but did a weight lifting regimen, and then finally, a group that received both the testosterone and did the weight training. Now it's probably not hard to guess which of these four groups saw both the most and the least muscle and strength gain. Obviously, the group that received both testosterone injections and did the weight training saw the greatest gains, and the group that did nothing at all saw the least. But here's where things get interesting. The group that weight trained with no testosterone and the group that received testosterone but didn't do any weight training at all saw pretty comparable strength gains on most lifts, and the testosterone group even outperformed the weight training group in some areas, like amount of fat-free mass gained. Gaining muscle mass is the primary motivation of most guys when they go to the gym, and this study is suggesting that injecting testosterone and never touching a weight may actually be more effective at achieving this goal than actually getting your ass to the gym and doing the work. Huh. So, just theoretically speaking, if somebody were to go about purchasing this testosterone, where might they do that, just so I know to avoid those sites in the future, obviously. Now we've strayed pretty far away from cycling and endurance sports at this point. Probably you can get jacked by taking testosterone, but a lot of cyclists would actually prefer to keep excess muscle mass to a minimum. Is testosterone really a concern for this type of athlete? Well, the answer is yes, and cyclists have cheated by injecting themselves with testosterone. The benefits may be less obvious than with, say, EPO, for example. As I said, pro-cyclists are generally not trying to gain excess muscle mass, but keep in mind that testosterone also plays a role in protein synthesis, red blood cell production, and recovery. These are all important functions for an endurance athlete, but when we get into just how prevalent low testosterone is for this population in just a moment, it should become abundantly clear why a pro-cyclist would be so concerned about it. For example, it's been shown that at rest, testosterone appears to be lower in endurance trained men than in untrained men. This finding is so consistent that it actually has a name, Exercise Hypogonadal Male Condition, or EHMC. That's right, low testosterone levels are a shockingly common occurrence amongst highly trained endurance athletes. It appears that the more highly trained you are, the lower your testosterone levels are likely to be. For example, this study on Ironman triathletes found that of 22 men tested, only nine of them had a normal testosterone concentration, another nine fell into the gray zone, and four of them actually have levels low enough to suggest deficiency. This may be a bit surprising for some people. These are elite athletes that we're talking about, which is certainly not the population that you think of when you think of low testosterone. And despite this being a fairly common occurrence, it's not talked about that much. This also may be even more of a concern for older athletes. After all, testosterone naturally decreases as we age, and add in hard endurance training on top of that, and you could have a recipe for disaster. That being said, some of this may be explained by poor training practices amongst endurance athletes, namely over-training and under-fueling. Intensive training periods have been shown to reduce testosterone, and over the course of a three-week grand tour, a pro-cyclist testosterone will drop each week, and there's even evidence that detraining may have a positive impact on testosterone and testosterone to cortisol ratio. Over-training or working your body too hard and not giving yourself enough recovery will likely tank your testosterone. And unfortunately, over-training and under-fueling usually go hand in hand, and being in a caloric deficit is the second big kick in the nuts for your testosterone, that is. That being said, I don't want you to leave this video thinking that exercise and weight loss will automatically lower your testosterone levels because that is certainly not the case. In a sedentary population, exercise will actually increase testosterone, and in overweight men, losing weight will increase it as well. What's clear is that there's a sweet spot with the amount of exercise you get and how much you weigh in your testosterone levels. Sure, if you're an overweight couch potato, then your testosterone is probably going to take a hit, but on the other extreme, which is where most high-level endurance athletes lie, if you train too hard or too much and you diet too aggressively, that's also not good for your testosterone. The problem is that in order to continue making fitness gains, you need to continue pushing yourself further and further, so there likely will come a point where you're flirting with this line. So with the bad news out of the way, the question now becomes how much does low-test testosterone affect performance, how much does it affect overall health, and if you have low testosterone, what can you do about it? Let's start with this performance question. What I find interesting about this is that if the best endurance athletes frequently suffer with low testosterone, then why are they the best endurance athletes? Is testosterone really affecting their performance that much, or has their body learned to cope with it? This study on testosterone and competitive performance had runners increase their training volume by 25% for 12 weeks, followed by a four-week period of their normal training volume, and testosterone and cortisol were measured every four weeks throughout the testing period. Sure enough, this increase in training volume resulted in a drop in testosterone, and when the subjects went back to their normal training volume, testosterone went back up. This decrease was significant enough that about half the subjects would be classified as having clinical androgen deficiency. Despite this fact, performance actually improved, leading the researchers to conclude that decreases in testosterone and testosterone to cortisol ratio are not always indicative of compromised performance. And this is not the only study coming to this conclusion. Similar results have been found in pro-cyclists as well. All right, so testosterone levels don't matter then? Well, I wouldn't go as far as to say that. As this review on the topic states, a reduced testosterone concentration alone does not necessarily warrant treatment, but when it is accompanied by symptoms of hypogonadism, such as fatigue, sexual dysfunction, and or low bone mineral density, an athlete's performance and or health may suffer. This is really the key here. If you're training a lot, so much so that at times you may be teetering on that line of overtraining and you're really trying to get the most out of your body, then you should understand that your testosterone levels may take a hit. And this is normal for athletes doing what you're doing, and it may not even affect your performance. That being said, you can absolutely push this too far. And at the point that you start to experience chronic fatigue that never goes away or a complete loss of libido, then you may have a problem. Not only because your performance will start to suffer, but also because you may start to have health problems like low bone mineral density. This may be TMI, but I know that I'm getting overtrained when I start to lose any and all interest in late night bedroom activities other than sleep, if you know what I mean. Yeah, we get it. You're talking about sex. Also, we already knew that you don't get late. You didn't need to tell us. EHMC has been described as the male version of the female athlete triad, which involves disordered eating, the absence of menstruation, and osteoporosis. Weekly training volume is correlated with amenorrhea in women, just as it's correlated with a drop in testosterone in men. In other words, this is an issue that affects both sexes. The closer that you get to overtraining, the worse your reproductive system is going to function, regardless of whether you are male or female. And the term commonly used to describe this is reds, or relative energy deficiency in sport. So what you're saying is that if I don't take rest days, then I don't need to use a condom? You know, this video actually is turning out to be pretty useful. I gotta admit. The review concludes stating that treatment should be centered on non-pharmacological strategies, including nutritional intervention and modifications in training volume to improve energy availability and support normal hormonal function. Some of these strategies may include giving yourself planned rest periods in your training. There's a reason why so many coaches include recovery weeks, mid-season breaks, and off-season breaks in their training programs. The recovery is important for a wide variety of different reasons, but one that's often not cited is the hormonal effects. As we've already demonstrated in some of the studies that we've looked at, a recovery period can give your testosterone levels a bit of a boost after they've been lowered from a hard training period. It's also important to build your training slowly over time. For example, let's say that your current training volume is five hours per week, but you would like to be training 15 hours per week. You should not just add 10 hours per week to your current training volume and hope for the best. You should add volume to your training gradually, maybe adding one to two hours per week every week, and also including recovery weeks in there every three to four weeks until you reach your desired volume. You may have also heard that doing high-intensity interval training and heavy weight training boosts your testosterone, and there is certainly evidence that this is the case. This is just one more reason to add weight training and properly structured interval training to your program. However, I wouldn't necessarily rely on this to increase your testosterone levels because a lot of times this boost in testosterone is an acute change, not a chronic one. And also, if you're suffering from low testosterone because you're over-training, then adding more training, especially hard training, in the gym or with hard intervals will only make that problem worse. Now let's talk about dieting because that is an important part of this testosterone equation. Yes, a lot of us would like to lose weight in order to maximize our performance, but the same rules of increasing training volume apply to caloric restriction as well. Don't try to lose a bunch of weight all at once. Instead, you should be trying to lose it gradually over time so that you're still consuming enough calories to support normal hormonal function. It's also important to point out that even if you are losing weight in the right way, there is a point at which you will get so lean that your testosterone levels will start to suffer. This point varies from person to person, but it's important to be aware of. And also, keep in mind that lighter doesn't always mean faster, especially if you've hit this point. Your goal weight should be based on where you see your best performances, not necessarily the lowest weight that you can hit on the scale. And I already know that I'm going to get comments asking about testosterone boosting supplements and dietary practices. Honestly, that's probably a whole other video in itself, and perhaps I'll cover it in the future because there actually are supplements out there that do have science to back them up. No need to make that video, bro. Hypergain Beast Mode Testosterone Pro Max Booster in the birthday cake flavor is all you really need. And I'm sure it's perfectly safe and legal, or whatever. Before you go down the supplement route, though, I would make sure that you have your basics covered first. Which is a properly structured training plan with plenty of recovery built in that doesn't have you over-training and a well-balanced diet that doesn't have you under-fueling. Thanks for watching. If you're looking to step up your training, then I have links to online training plans and coaching down in the description below. Support me on Patreon if you'd like access to my weekly members-only Q&As. And finally, if you enjoyed this video, be sure to give it a like, subscribe, and share this video with your cycling friends. I'll see you in the next one.