Picture the sort of cyclist who has the potential to win the Tour de France. You see a really skinny guy, right?

You should.

Cyclists who excel riding uphill usually win the race, and according to Bicycling.com, the average climber in the TdF stands 5’8” to 5’10” and weighs between 132 and 145 pounds.

While you would expect that anyone who races 2,200 miles on a bike in 21 days would lose an extreme amount of weight, these climbers need to start their seasons super skinny, so they engage in a type of offseason training equally extreme.

Fat-burning rides.

These rides force their bodies to burn stored fat. They tend to be done in the morning for four or more hours at a moderate pace (for a pro), and little to nothing is eaten before or during the ride.

Chances are you have no absolutely no interest in riding or doing any form of moderate exercise for that amount of time, but you probably do want the end result. And you can cause your body to burn a higher percentage of body fat if you understand the science behind fat-burning rides.

Even while you do something as relaxing as sit and read this article, your body requires energy. But since the energy expenditure required to hold the newspaper and drink coffee doesn’t require an increased amount of oxygen, up to 80 percent of the energy used comes from fat, a fuel that your body stores in abundance.

Even those super-skinny pro cyclists, for instance, possess enough stored fat to fuel a 100-hour run.

When you put down the paper and walk the dog, you begin to use more oxygen. As a result, your body begins to burn a higher percentage of carbohydrates, the body’s preferred and fastest energy source.

Walk at a moderate pace and — if you’re in good shape — about 50 percent of the energy used comes from carbs and 50 percent comes from fat. Increase the pace to the point where you need to catch your breath after a speaking sentence or two, and carb burn increases to about 70 percent.

Take on the longest hill in your town at the same brisk pace, and the percentage increases to about 85 percent. Run up that hill as fast as you can and your energy comes from close to 100 percent carbohydrates.

Now let’s have you hop out of bed and unto a bike without eating breakfast.

You ride at a more-than-leisurely pace, but not a brisk one. Only an occasional climb increases your effort to the point where you lack the breath to finish a full sentence.

If you’re in good shape, a ride like that would be fueled by a mix of about 65 percent carbs and 35 percent fat — if it ended in less than two hours.

If it goes longer, however, the ratio changes for a simple reason: Your body has no more carbs to burn.

Without carbs, your body increases the percentage of fat burned to about 85 percent and gets the rest by from protein, often by catabolizing muscle. That’s why foods and drinks marketed for use after exercise maintain a 4-to-1 ratio of carbs to protein and why you need to eat some protein along with mostly carbs if you want to recover optimally after exceptionally long or intense bouts of exercise.

Force your body to exercise after it’s out of carbs a few times a week, and it learns to adapt. Subsequently, it begins to burn a higher percentage of fat during less-than-intense exercise so that some of your body’s preferred fuel, carbohydrates, remains for more intense efforts.

Unfortunately, instead of positively readjusting what’s called the body’s set point by engaging in fat-burning rides or similar exercise, most people do the opposite. They create a higher set point by eating unhealthy food, eating an excess of any food, and failing to exercise long enough, hard enough, or at all.

There are many things you can do besides those crazy four-hour rides on an empty stomach to make your body more likely to burn body fat, especially if you occasionally splurge and consume excess calories. One such strategy is to increase the percentage of protein ingested while greatly reducing or even eliminating your consumption of simple carbohydrates.

But equally beneficial, it seems, is before-breakfast exercise at a moderate rate of intensity — provided you eat right the rest of the day.

Now, I know this can be a hard sell, but here’s the suggestion’s saving grace: Just like taste buds get accustomed to sugary foods, your muscles and your mindset eventually adjust to working out early and in the fasted state.

I started early-morning exercise while still in college, and it was a struggle — for about three weeks, the oft-quoted amount of time it takes any new pattern to become habit.