If walking the best exercise on the planet? Yes and I’ll prove it below.
Can walking boost your testosterone? Probably for the majority of men on this site, the answer is a resounding ‘yes’. “How?” you ask. Let me give you three ways that walking can give most men a very significant boost in testosterone even if they do nothing else for their health:
Walk weight loss 27100 = 900 per day
1. Weight Loss. Let’s say you are the typical overweight male that weighs about 200 pounds. And let’s say you really dislike gyms, biking, jogging and almost all forms of exercise. Nevertheless, you decide that you can walk for an hour. And you even decide that you can keep up a decent pace of about 4.0 mph. That’s a brisk pace but doable for most males – a 15 minute mile.
This is not unreasonable and most men can do a half hour in the morning and a half hour at either lunch of dinner. (A walk with your woman will get her health and libido going too.) And here’s the beauty of an hour of walking: it will burn 400 calories per day. Now if you can bump up the time just a bit more, you can burn 500 calories per day. Of course, the significance of 500 calories per day is that it is 3,500 per week which is 1 pound of fat.
That may not sound like much, but losing one pound of fat per week would be 50 pounds in one year. What does this have to do with testosterone? Just keep that 50 pound number in mind below and consider these studies:
a) One study of men that lost 50+ pounds found an average increase in total testosterone of almost 60%.  This is a huge number and even exceeds the increase seen in men with apnea.
b) It is possible that some men may even experience more dramatic increases. One study compared the average testosterone of very obese men and compared them with age-matched controls and found the difference in testosterone was over double! 
In other words, depending on how overweight you are, you can very significantly boost your testosterone. Again, normally when someone tries to lose weight, they cut calories rather significantly which causes a big problem: if you drop calories too rapidly, you will also likely greatly reduce your testosterone. See this link on Dieting and Testosterone for more information.
NOTE: You do have to make sure to lose weight though. And if you think you have low testosterone: get tested! Low testosterone can carry with it certain serious health issues such as anemia and osteoporosis, so work with your doctor.
2. Cortisol. One of the big objections that some knowledgeable people will put out there to this page is something along the lines of:
“Walking can’t increase cortisol, because all aerobic exercise increases cortisol and cortisol will lower testosterone.”
There is some truth to this statement. However, what is not so well known is that walking can actually lower cortisol. This is remarkable if you think about it: exercise is normally considered a stressor because it increases the oxidative and cortisol load on the body. However, that is a generalization that is NOT always true. Some exercises (Judo) can actually increase improve oxidative status. And some exercises can actually lower cortisol as strange as it may sound.
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One of those exercises is walking if done correctly. Of course, it probably won’t surprise you that both the duration and intensity has been found to affect post-exercise cortisol levels.  One could call that a “no brainer.” However, what one Japanese study showed is that young, healthy men who walked in a forest setting actually experienced a significant drop in cortisol.  The walk was actually relaxing for these men and produced an anti-stress response and this was in contrast to walking in the city.
Other studies have shown that you don’t have to be in nature to get a nice drop in cortisol post-exercise.  This same study showed that brisk walking – in other words you don’t have to walk leisurely to avoid a cortisol rise – resulted in both lowered cortisol and improved mood. Of course, you can “go crazy” with walking and a couple of studies have shown that lengthy walks can lead to elevated levels of cortisol. The most extreme example is probably a study of those on a lengthy and intense walking race where the participants experinced both a rise in cortisol and a decrease in immune function. 
So the bottom line is: just walk. Enjoy yourself. Break it up into several times per day and make sure you feel good afterward. This will have huge health benefits. Remember: we were born and build to walk.
3. Estrogen. Why does losing weight increase testosterone so much? Well, there are likely a number of reasons, but the primary one is the reduction in testosterone. The more fat you have, the more aromatase you have which is the enzyme that converts testosterone to estrogen. So think about the beauty of walking: it can decrease cortisol and decrease estrogen Both of these are going to increase testeosterone for many men in and of themselves.
So think about this: walking is considered the most boring, lowliest form of exercise by a big percentage men and probably the least manly. (I guess ballet in a pink tutu might rank a little higher.) Yet men that walk are usually boosting erections, raising the “male” hormone testosterone, lowering the “female” hormone estadiol/estrogen and decreasing the muscle-wasting hormone cortisol. What gets more manly than that? (Actually, weight lifting is very similar, but almost all other forms of exercise will increase cortisol and in many cases decrease testosterone.)
Again, what else could you ask for? Every minute that you are walking will help supercharge you in the bedroom.
4. Dopamine. In #2 above we covered how walking can lead to improved mood if done correctly. This is probably from the increased dopamine that comes from reasonable exercise. (See this link on Natural Dopamine Increasers for more general information.) So what does increasing dopamine have to do with testosterone?
Well, dopamine is highly tied to sexual desire and activity and has been shown in multiple studies to be so linked. In fact, many studies have shown that testosterone, for example, works its wonders by increasing dopamine in the brain, which then leads to increased copulations. 
However, the reverse is very likely true in the long term as well. Remember: anything that increase sexual intercourse frequency is likely to increase testosterone as well. Thus, anything that decreases cortisol and increases dopamine (both of which will improve mood and libido) will very likely lead to medium term testosterone increases. Nice! Read my link on Sex and Testosterone to see the research that shows that this is indeed the case.
5. Erections. I’ve already covered this in detail in my link on Walking and Erections. Every minute you spent walking will increase your hardness factor. I’m a gym rat and love it, but I have to admit something: 99% of people hate the gym and won’t last over two months. But everyone can find a place to walk: in a mall; in a park; over lunch at work. And this will improve erectile dysfunction in many. many ways. And the same logic applies as in #2: anything that increases the frequency of sexual intercourse is likely to increase testosterone over time.
5. Overtraining and Injuries. As I’ve shown in my link on Weight Training and Testosterone, pushing that iron can lead to long term testosterone gains according to several studies. But does it always? I doubt it and I’ll tell you why in one word: overtraining and injuries.
I meet one guy after another in the gym recovering from torn biceps and shoulders, bad backs, etc. And they all have one thing in common: it’s touch to exercise! And without exercise many health problems begin to set in and, no, this is not likely to be good for your testosterone.
Overtraining is a stressor and can lead to elevated cortisol and decreased testosterone – many studies have shown this. And, if the overtraining is bad enough, can take the person out of commission for months with decreased immune function, sleep disorders and so on. (See my link on The Problems of Overtraining.)
6. Time With Your Woman. If you can talk her into it, walking is one of the best exercise to build up your relationship. Yes, if you don’t walk too fast and are in half way decent shape, you can actually talk and carry on a conversation – yes, the way Mother Nature intended it – with the the woman you love. And you’ll both be increasing your nitric oxide, slimming your waists and stimulating blood flow. And that always translates to increased activity in the bedroom, eh Walking Man?
So, again, there is no study that proves that walking increases testosterone, but, if you do it right, it will likely give you a little boost. So get out and hit the pavement, the sidewalks, the parks and the treadmill and walk, walk, walk, walk…
1) The Journal of Clinical Endocrinology & Metabolism, May 1 1988, 66(5):1019-1023, “Effect of Massive Weight Loss on Hypothalamic Pituitary-Gonadal Function in Obese Men”
2) The Journal of Clinical Endocrinology & Metabolism, Dec 1 1977, 45(6):1211-1219, “Low Serum Testosterone and Sex-Hormone-Binding-Globulin in Massively Obese Men”
3) Int J Obes (Lond), 2007 Dec;31(12):1786-97, “A dose-response relation between aerobic exercise and visceral fat reduction: systematic review of clinical trials”
4) Journal of Applied Physiology, Feb 1 1976, 40(2):155-158, “Effects of exercise on excretion rates of urinary free cortisol”
5) Journal of PHYSIOLOGICAL ANTHROPOLOGY, 2007, 26(2):123-128, “Physiological Effects of Shinrin-yoku (Taking in the Atmosphere of the Forest) Using Salivary Cortisol and Cerebral Activity as Indicators “
6) Journal of Psychosomatic Research, May 1992, 36(4):361 370, “Efficacy of Tai Chi, brisk walking, meditation, and reading in reducing mental and emotional stress”
7) Life Sciences, May 17 1996, 58(25):2337 2343, “50-mile walking race suppresses neutrophil bactericidal function by inducing increases in cortisol and ketone bodies”
8) Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology, May 2002, 132(1):37 55, “Interactions between aromatase (estrogen synthase) and dopamine in the control of male sexual behavior in quail “
9) Brain Research Bulletin, 1997, 44(4):327 333, “Testosterone, Preoptic Dopamine, and Copulation in Male Rats”