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Bicycling to work is one of these "small things" that may make the difference between lean and obese.

I know this is not what your friends will want to hear, but for 99.9% of them it's not their genes which are to blame for their inability to lose weight. It's much simpler than that: It's their inability or unwillingness to induce a large enough caloric deficit to force their bodies to tap into the fat stores. Don't get me wrong: It's obvious that genes, with their direct and indirect influence on one's basal energy requirements (think of being tall vs. being small, if nothing else), amount of muscle, and even ability to handle glucose and fats, will factor in here. In the end, however, it's everyone's knowledge about the dos and don'ts of dieting, effort and dietary adherence that will make the difference.

That's no news for you? I think the results of a recent study from the University of Kansas Medical Center and the Texas Tech University will still come as a surprise. Usually, we talk about cheating on one's diet, skipping scheduled workouts and eating foods people are not supposed to eat, when we discuss the reasons why people fail. The results of said study, however, suggest that something else may have a much larger impact: Our regular non-exercise physical activity.
If you've read my March 2015 article "It Doesn't Have to be an Exhaustive Workout - Increasing Physical Activity Just as Effective as Strength, Endurance or Combined Exercise to Lose Fat and Build Muscle" (read it now), you will know about the importance of "taking the stairs", standing instead of seating, bicycling to work and other often overlooked low-intensity non-exercise physical activity in our everyday lives. Interestingly enough, it is just this type of low intensity 'non-exercise' of which the so-called "Midwest Exercise Trial 2" indicates that it is what distinguishes the weight loss responders (>5% weight loss) from the non-responders (<5% weight loss) in a relatively tightly controlled "work out five times per week for 10 months to lose weight"-intervention by Herrmann et al. (2015).

Before we are dealing with this surprising result, though, let's first take a look at what exactly the N=141 18-30 year-old men overweight/obesity (BMI 25-40 kg/m²) subjects had to do in this 'exercise for weight loss study' (details can be found in the description the scientists published when they registered their clinical trial | Donelly. 2012):

• Table 1: It is important to note that there were no sign. baseline differences in weight, age, etc. between responders and non-responders among the study participants (Herrmann. 2015).

  the subjects exercised on 5 days of the week - one of the session was "choose the activity you want", the other sessions were performed under supervision walking/jogging on treadmill
• the duration / intensity of all workouts was matched to initially burn 150 kcal; from months for on, 400 and 600 kcal/session (this is in line with the "2008 Physical Activity Guidelines for Americans" | USDA. 2008) 

I see you're looking for the dietary advise? Well, there was none. That may look awkward, but in view of the fact that the scientists wanted to see whether the simple adherence to the USDA "Physical Activity Guidelines for Americans" would make a difference, the subjects were told to stay on their regular (junk food?) diets.
As the name of the study or rather the index "2" in the name implies, the "Midwest Exercise Trial 2" is a follow up study. It's a follow up that was supposed to elucidate (a) what distinguishes responders from non-responders and whether (b) the gender differences in weight response Donelly et al. observed in their 2003 predecessor study were coincidental or something we have to keep in mind, whenever we are designing exercise-based weight loss routines for men and women..

Figure 1: Total daily energy expenditure (TDEE), nonexercise energy expenditure (NEEx), and resting metabolic rate (RMR) at baseline and 10 months in responders (RS) and nonresponders (NR) to an aerobic exercise intervention.

What should I say? If you look at the data it would almost seem as if (2) was the case: Men and women appear to respond very differently to this kind of exercise-based weight loss efforts. Yes, the data in Figure 1 shows that there is a trend for non-responders from both sexes to be less active in their free time and thus having a lower non-exercise induced energy expenditure (NEEEx). On the other hand, though, ...

1. Figure 2: Nonexercise physical activity (NEPA) and sedentary time across 10 months in responders (RS) and nonresponders (NR) to an aerobic exercise intervention (Herrmann. 2015).

   only the male non-responders are truly characterized by their tendency to take the five weekly workouts as an excuse to use the elevator and drive the 200m to the next fast-food outlet by car, while 
2. there is no such compensatory effect on NEEEx in the women and even an increase in resting metabolic rate (so no metabolic damage or shut-down) in the female non-responders

This trend for a "compensatory effect" on non-exercise physical activity (NEPA) in male and its absence is in female non-responders becomes even more obvious in Figure 2.

Figure 3: Rel. energy balance in male and female weight loss responders and non-responders in month 10 - data calculated as (total intake / total expenditure - 1)*100 based on data from Herrmann et al. (2015).

If we go back to my initial comment on caloric deficits and do the math that's required to calculate the relative difference between the total reported energy intake and the estimated energy expenditure, we get an excellent explanation for the fact that the male "non-responders" don't lose weight: They simply weren't in caloric deficit (see Figure 3); and that - and this is actually the most interesting finding - not because they ate more (the reported energy intake didn't change much), but because they moved less in their everyday lives!
References:

• Donnelly, Joseph E., et al. "Effects of a 16-month randomized controlled exercise trial on body weight and composition in young, overweight men and women: the Midwest Exercise Trial." Archives of Internal Medicine 163.11 (2003): 1343-1350.
• Donnelly, Joseph E., et al. "A randomized, controlled, supervised, exercise trial in young overweight men and women: the Midwest Exercise Trial II (MET2)." Contemporary clinical trials 33.4 (2012): 804-810.
• Herrmann, Stephen D., et al. "Energy intake, nonexercise physical activity, and weight loss in responders and nonresponders: The Midwest Exercise Trial 2." Obesity 23.8 (2015): 1539-1549.
• Klesges, Robert C., Linda H. Eck, and JoAnne W. Ray. "Who underreports dietary intake in a dietary recall? Evidence from the Second National Health and Nutrition Examination Survey." Journal of consulting and clinical psychology 63.3 (1995): 438.
• USDA, Physical Activity Guidelines Advisory Committee. "Physical activity guidelines for Americans." Washington, DC: US Department of Health and Human Services (2008): 15-34.
• Poppitt, S. D., et al. "Assessment of selective under-reporting of food intake by both obese and non-obese women in a metabolic facility." International journal of obesity and related metabolic disorders: journal of the International Association for the Study of Obesity 22.4 (1998): 303-311.
• Smith, Wayne T., Karen L. Webb, and Peter F. Heywood. "The implications of underreporting in dietary studies." Australian journal of public health 18.3 (1994): 311-314.

Wouldn't it be great if  Taubes was right and you could sit your lazy flat-ass even flatter without having to worry to miss a chance of losing weight?

The idea that you can lose weight only by working out (most people even think of "cardio") is as hilarious as it is ingrained in the Western cultural believes. In fact, the fact that some studies indicate that overweight individuals end up losing weight when they are (often put) on an exercise regimen, however, does not mean that their workouts "pulled the trigger". Rather than that, their ability to lose weight is a consequence of an incomplete compensation of the extra-energy expenditure... and yes, I am talking about calories in vs. calories out here, because, in the end, the energy balance is what counts - even if energy intake and output must not be seen as independent quantities (learn more).

So, if exercise will only help you lose weight, if you don't fully compensate for the exercise induced extra-energy expenditure, the obvious and important question is: What determines to which extent the extra-energy that's consumed by your muscles during physical activity is compensated for?
In a recent systematic review, Marie-Ève Riou and colleagues tried to answer this very question. To do so, they reviewed the contributions of sex, age, initial adiposity, as well as duration, dose, frequency and intensity of exercise in 61 studies with a total of 928 subjects. And what the researchers from the University of Ottawa found is a complex conglomerate of data that requires careful consideration and interpretation.

• Firstly, the overall mean energy compensation was 18% ± 93% - This may suggest that the average subject lost weight, but with a margin from -75% to 111% that's far from significant. And still, on average, the data indicates that exercise does not make those who get off the sofa and move their a$$ more hungry (one has to keep in mind, though, that not all of the studies allowed their subjects to eat as much as they wanted; in some cases where the energy compensation is negative, the subjects were simply required to diet)
• The analyses indicated that 48% of the variance of energy compensation is explained by the interaction between initial fat mass, age and duration of exercise interventions. The scientists even came up with an equation to determine the energy compensation in % for young and old individuals, respectively:
  
  
  What both equations have in common is the fact that a constant coefficient is divided by the duration in days. In other words: The longer people exercise, the more they compensate, the lower the exercise-induced energy deficit.

• It's also interesting to take a look at the more complex graphs of a model that includes the other two previously mentioned parameters: Age and fat mass at the beginning of the study.
  

  Figure 1: Fat mass (FM), age, duration of the exercise intervention and degree of energy compensation (100% compensation = no energy deficit, -200% = sign. appetite suppression + huge deficit | Riou. 2015)

  As you can see in Figure 1, fat, young individuals benefit most from exercise. Initially, they don't compensate at all for the extra-energy expenditure, but rather reduce their energy intake for every 1kcal/day they burn by another 2kcal/day (that's why the graph starts at - 200%).
• Sex, frequency, intensity and dose of exercise energy expenditure were not significant predictors of energy compensation. This is a bit surprising, as previous studies had suggested that women may be a bit more susceptible to exercise induced overeating (=overcompensation) than men, and that HIIT may less prone to cause people to compensate for the extra-energy they burnt than longer duration steady state exercise, but obviously these effects haven't been consistently observed in the studies the scientists reviewed.

The most important message, however, is the fact that the longer you train (=adhere to an exercise regimen, not "60 min vs. 20 min"!), the more you tend to compensate for the extra energy you burn.
References:

• Riou, Marie-Ève, et al. "Predictors of Energy Compensation during Exercise Interventions: A Systematic Review." Nutrients 7.5 (2015): 3677-3704.