Are you carbophobic? Many men are now, because there is so much anti-carb sentiment out there in the (American) health blogging world. This is tragic for many reasons. Below I will show you why the great majority of men not only needs carbs but an abundant supply for several simple reasons:
a) For intense exericse
b) For optimal muscle growth
c) For maximum colon health
Let's start with the first item - exercise. I believe most men recognize that exercise is foundational to a healthy lifestyle and, for those doubters, remember that exericse is one of the best ways to naturally boost nitric oxide. For a dozen other great reasons, see my page on Exercise and Sexual Health. And I believe that the research clearly shows that, in all but the most rudimentary of exercise programs, carbohydrates are essential. NASM (National Academy of Sports Medicine) does an excellent job in my opinion of summarizing the evidence for this:
"The amount of carbohydrate in the diet can affect performance. High-carbohydrate diets increase the use of glycogen as fuel, where as a high-fat diet increase the use of fat as fuel. However, a high fat diet results in lower glycogen synthesis. This is of particular concern if the individual is consuming a reduced-energy diet. For the endurance athlete, a carbohydrate-rich diet will build glycogen stores and aid in performance and recovery. Although some studies show an increase in performance associated with the consumption of a high-fat diet, these improvements are seen in exercise at a reliatvely low intensity (less than 70% of VO2max). As the intensity of exercise increases, performance of high-intensity exericse will ultimately be impaired." 
Basically, lower intensity exercise such as slower jogging and walking can be handled with a fat-based diet. However, most exercise programs are based on periods of higher intensity. How many of us are ultramarathoners after all? Most men want to lift weights, power lift, increase our speed on a bike and running, do an aggressive HIIT routine, etc. All of this requires higher intensity levels and those higher intensity levels demand ample carbohydrates. In fact, not have those carbohydrates could contribute to overtraining.
NASM goes on to recommend between 2.7 and 4.5 grams of carbohydrate per pound of bodyweight. That's actually a lot of carbs and. for me, a 167 pound guy would mean between 451 and 751 grams of carbs per day. As I'll show below, I don't feel that I need quite this many carbs, because I don't really consider myself an "endurance athlete." I am serious about my exericse programs and try to exercise an hour and get in 13,000-14,000 steps per day. So, even though I am not really an "athlete," I still need a good supply of carbohydates. In particular, I lift weights quite intensely and do either HIIT or cardio (treadmill running). I cannot imagine trying to do those without carbohydrates!
You also have to have those carbs to really build muscle. Yes, you can put on some muscle with lower carb diets, but most of you into bodybuilding know that insulin is often considered just as anabolic as testosterone. In fact, that's the purpose of those post workout drinks that men consume after lifting: they are trying to spike their insulin levels to drive the amino acids they have consumed into muscle cells. Of course, I don't advocate spiking your blood sugar and insulin, but some carbs will help with that process. The Journal of the International Society of Sports Nutrition points out the scientific principle behind this strategy:
"A combination of a fast-acting carbohydrate source such as maltodextrin or glucose should be consumed with the protein source, as leucine cannot modulate protein synthesis as effectively without the presence of insulin and studies using protein sources with a carbohydrate source tended to increase LBM more than did a protein source alone. Such a supplement would be ideal for increasing muscle protein synthesis, resulting in increased muscle hypertrophy and strength." 
Thus, the protocol after a weights, power lifting, kettleballs, etc. is to consume protein and carbs within about 20 minutes. There are still other exercise-related reasons to consume carbs: a) if you workout goes over 90 minutes, b) a post-meal drink for endurance athletes to maximize glycogen synthesis and stores and c) glycogen loading. You just can only go so far with an exercise program that does not include carbohydrates and, in my opinion, every man needs to be serious exercise.
NOTE: You also desperately need the fiber and resistant starch that comes with complex carbohydrate foods for proper colon/intestinal health.
GOOD CARBS AND BAD: Yes, refined carbs are bad - no one disputes that. Complex carbs are the core staple of virtually superculture on the planet. Just as there are good fats that you should emphasize and bad fats that you should demphasize, there are good carbs and bad carbs. Good carbs are complex carbohydrates with various forms of fiber. These are be nutrient-packed and loaded phytonutrients. They also are generally replete with nitric oxide-boosting compounds that will help men in a hundred different ways, which is the subject of my book The Peak Erectile Strength Diet.
One of the keys is to consume low glycemic carbs. Dr. Barnard has show that you can reverse adult onset diabetes with lots of carbs and a low fat diet as long as they are low glycemic. (See my page on Low Fat Diets and Diabetes.) Beans, legumes and fruit tend to be lower glycemic for example. NOTE: Wheat, even whole wheat, is NOT lower glycemic and neither is white or basmati rice. Deemphasize these foods.
NOTE: No, too many carbs do NOT make you fat contrary to what so many health bloggers claim. Too many calories make you fat!
While it is critical to consume an ample amount of complex carbohydrates, it is also critical to not go too high. Below are just a few reasons:
1. Elevated Triglycerides and Lowered HDL. If you consume too many carbs, you could find that your triglycerides climb up and your HDL falls. This is a sign of insulin resistance setting in and could accelerate the buildup of plaque in your arteries. See my page on HDL, LDL and Triglycerides Levels for Plaque Regression.
2. Go Pattern B with Your Lipids. If you consume too many carbs, you could find that your LDL becomes smaller and your LDL particle count goes up. The particle count (LDL-P or apoB) is probably the single most important number to maintain and control arterial plaque. See my page on LDL-P Particle Count Levels for more information.
3. Raise Post-Prandial Blood Glucose Levels. Probably the best test for insulin resistance is post-meal blood glucose levels. As prediabetes sets in - and this is incredibly common in modern cultures - your post-meal blood glucose will begin to spike. This can hammer the beta cells in your pancreas and send a man into adult onset diabetes. See my page How to Test for Insulin Resistance for information on how to perform this basic best..
Every man is different as to how many carbs he can consume and it requires testing and monitoring, something that should become part of your health and fitness lifestyle if it is not already.
So how do you actually choose your carbohydrate levels? I am going to assume you know about how many calories you want per day. If you don't, I will do a post soon on how to estimate your base calories. For now, I will just assume that it is 2,200, but you can adjust accordingly.
1. STEP 1. Choose a Superculture (For Fat Levels). You must start by deciding a few all-important macronutrient percentages that you want in your diet, such as the level of fat. There are basically 3 options:
a) Low Fat. The ultra elite supercultures that have no cancer or heart disease AND incredible longevity all eat low or lower fat diets. The Tarahumara are probably the lowest fat of these cultures with fat calories in the 10-15% range of total calories. You can read more about them in my page on The Tarahumara Diet. (They are also famed ultramarathoners.) I prefer this kind of diet to maximize nitric oxide and blood flow. In addition, the most elite supercultrues fall in the range and you can read about others in my review of the book Healthy at 100.
b) Mediterranean or Pukapuka Diet Fat Levels. This would be fat levels in the 30-35% range. The Mediterranean Diet has had good health outcomes overall and the Pukapuka have nearly perfect heart health. You can read about them here if interested: The Pro-Testosterone Diet of the Tokeluau and Pukapuka.
c) Tokeluau or Paleo Diet Fat Levels. In my opinion, the highest level that one would want to consider is 35%. However, there is another Pacific Island group that eats fat in the 50% range and discussed in the link above. Many of you are consuming what I call "classic Paleo Diets" and my be more comfortable at this level.
2. STEP 2. Choose a Level of Protein. Most guys trying to put on muscle or significant exercise will go higher on their protein levels. I am going to assume below that this is the case, simply because almost every guy on the Peak Testosterone Forum seems to be in this category. If you don't care much about protein, adjust accordingly. By the way, contrary to the bodybuilding magazines, you don't need a g/lb of body weight. The actual ACSM guidelines for strength athletes is 1.2 - 1.7 g/kg, which works out to about 0.55 - 0.77 g/lb. So, for example, I am 167 pounds and lifting weight regularly but am not a competitive bodybuilder obviously. I need about .65 g/lb, which works out to about 108 grams of protein per day, which would be about 20% of my calories. This is the number I will use below.
3. STEP 3. Calculate Your Carbohydrates Per Day Based on the Above. Those of you familiar with macronutrient calculations can do this on your own, but for those unfamiliar, I have included three sample sets of numbers based on the which fat level is chosen and assuming total calories of 2,200 and that 20% of those calories are protein:
Notice that the carbs per day is between 165 grams per day and 358 grams per day, depending on how much fat you include in your diet.
4. STEP 4. Calculate Your Carbohydrates Per Meal. This gives you a rough gauge as to how many carbs will be consumed with each meal. I eat around 6 meals per day and so basically I need 358/6 = ~ 60 grams of complex carbohydrates per meal. This is not something rigid and, after a day or two, you can quickly learn how much carbohydrate to add to your meal without getting out a laboratory scale for measurement.
1) NASM Essential of Personal Fitness Training, Fourth Ed. Revised, Jones & Bartlett Learning, p. 480
2) http://www.jissn.com/content/9/1/54 , Journal of the International Society of Sports Nutrition , Vol. 9, "Protein timing and its effects on muscular hypertrophy and strength in individuals engaged in weight-training"