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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.

If Yap et al. were right and only continuous and not accumulative physical activity mattered, activity trackers like the this would be useless. No one needs a device to remind him of the 30 min of brisk walking he did / skipped today.

In today's installment of waredownloadsoft "On Short Notice", we're going to take a closer look at a selection of recent papers from the European Journal of Applied Physiology. To be more specific, I will discuss the physiological and psychological effects of dietary nitrate and their potential significance for team athletes. From there we're taking a detour to glycogen resynthesis and its interaction with hydration - a topic that may be highly relevant for bodybuilders and at least interesting for everyone else. Before we then take a departing look at the differential effects of 5x10, 10x10 and endurance exercise on markers of protein synthesis and glucose uptake, we'll spend briefly review the claim that the cumulative physical activity (the one you measure w/ step counters) would lack the characteristic health benefits everyone expects from meeting his daily activity goals.

• Dietary nitrate improves sprint performance and cognitive function during prolonged intermittent exercise - While anyone of you should know that nitrate from beetroots can have significant physiological effects, the observations Thompson et al. made in their recent double-blind randomised crossover study are probably real news and above all practically relevant for some of you and/or your clients from various athletic domains (Thompson. 2015).
  
  To investigate the effects of dietary NO3(-) supplementation on exercise performance and cognitive function, the scientists had 16 male team-sport players consume NO3(-)-rich (BR; 140 mL/day; 12.8 mmol of NO3(-)), and NO3(-)-depleted (PL; 140 mL day/1; 0.08 mmol NO3(-)) beetroot juice for 7 days (these are the regular shots you can buy at supplement stores | if you want to drink regular beetroot juice, you need 3-4x the amount). With the nitrate supplement being consumed over a one week period we are thus not talking about the effects of acute, but about the effects of chronic supplementation. Keep that in mind, if you buy one shot and don't feel the results immediately.
  
  On the test day the subjects completed a prolonged intermittent sprint test (IST) protocol (two 40-min "halves" of repeated 2-min blocks consisting of a 6-s "all-out" sprint, 100-s active recovery and 20 s of rest) on a cycle ergometer during which cognitive tasks were simultaneously performed.

  Figure 1: Comparison of total work during the sprints and reaction times during cognitive decision making tasks designed to emulate the cognitive tasks during team sports (Thompson. 2015).

  As you can see in Figure 1 both, the total work done during the IST, as well as the reaction times that were measured during cognitive tasks in the second half of the IST, were improved in the beetroot vs. placebo trial.
  
  Even though, the scientists didn't find a difference in response accuracy, the findings are highly relevant for any athlete who has to (a) perform at high intensities, while (b) maintaining optimal cognitive performance and decision-making reaction times. Who is that? Well, I'd say almost every team sport athlete of whom previous studies have shown that his / her cognitive acuity suffers during prolonged intermittent exercise. 
• Extra water is not necessary for optimal glycogen replenishment after workouts - In fact, bodybuilders may want to avoid it... Avoid water? No, I am not saying you should not drink water at all, but if you look at the results of Valentín E. Fernández-Elías' recent "analysis of the relationship between muscle water and glycogen recovery after prolonged exercise in the heat in humans" you will see that too much water in the post-workout window may actually give you the 'watery' look some physique athletes like bodybuilders are trying to avoid.
  
  It is usually stated that glycogen is stored in human muscle bound to water in a proportion of 1:3 to 1:4 g. In their latest study, the scientists from the University of Castilla-La Mancha investigated this proportion in biopsy samples that were taken when their trained subjects recovered from prolonged exercise in the heat:

  "On two occasions, nine aerobically trained subjects (VO2max = 54.4 ± 1.05 mL/kg/min; mean ± SD) dehydrated 4.6 ± 0.2 % by cycling 150 min at 65 % VO2max in a hot-dry environment (33 ± 4 °C). One hour after exercise subjects ingested 250 g of carbohydrates in 400 mL of water (REHLOW) or the same syrup plus water to match fluid losses (i.e., 3170 ± 190 mL; REHFULL). Muscle biopsies were obtained before, 1 and 4 h after exercise" (Fernández-Elías. 2015).

  In contrast to what you may have expected, the muscle glycogen replenishment was not impaired by the lack of water in the REHLOW group. Ok, if you look at the data in Figure 2 right, there is a minimal advantage for the adequate water group, but this advantage is not statistically and almost certainly not practically relevant (79 ± 15 and 87 ± 18 g/kg dry muscle; P = 0.20).
  

  Figure 2: Muscle water content before and after dehydrating exercise and after 3 h recovery period (a). Muscle glycogen content before and after dehydrating exercise and after 4 h recovery period (b). Data is presented as mean ± SD. *Different from previous time point. †Different from REHFULL (P < 0.05 | Fernández-Elías. 2015).

  The thing that did differ between the adequat (REHFULL) and the inadequate (REHLOW) hydration trial, however, was the muscle water content which was significantly higher in the REHFULL than in the REHLOW trial (3814 ± 222 vs. 3459 ± 324 g/kg dm, respectively; P < 0.05; ES = 1.06).
  
  

  waredownloadsoft Suggested: "Hydrated or Dumb: Dehydration Affects Brain, Muscle and Other Vital Organs - Plus: 15+ Causes of Dehydration + Can the Color of Your Urine Tell You if You Drink Enough?" After reading this SV Classic and my recent article about the link between dehydration and type II diabetes you will probably stop thinking about using dehydration more than just occasionally.

  What's even more striking is that the scientists analysis of the ratio in which water and glycogen were stored in the two groups showed that subjects in the REHLOW trial stored the glycogen at the minimal 1:3 glycogen : water ratio, while their peers who got plenty of water exhibited a glycogen : water ratio of 1:17. Needless to say that this difference in water storage may be very important for bodybuilders during the last days and hours of their contest prep. In view of the importance of optimal hydration for your health, cognition and the hitherto unproven hypothesis that increases in cellular water may be involved in the hypertophy response to exercise (including the efficacy of creatine | Op‘t Eijnde. 2001), (non-)rehydration practices as they were used in the study at hand are nothing I would generally recommend. 
• Study says: Only continuous, not accumulated 30 min of walking will improve your glucose sensitivity - While step counters suggest that all you have to do to improve your health is to take "X" steps per day, the conclusion of a recent study from the DSO National Laboratories in Singapore refutes the simple and beautiful idea that you can distribute the X number of steps you would usually take during 30 minutes of brisk walking over three or more small "exercise servings" and see the same benefits as you'd see with 30 minutes of continuous brisk walking:

  "These findings demonstrate that 30 min of brisk walking is sufficient to improve insulin sensitivity in healthy, young Asians but only continuous and not accumulated walking provides this benefit. " (Yap. 2015).

  In said study, twenty-five healthy participants (12 males) participated in an oral glucose tolerance test (OGTT) the morning after: (i) accumulating three 10 min bouts of walking the previous evening; (ii) walking continuously for 30 min the previous evening or; (iii) resting the previous evening. Blood samples were taken in the fasted state and for 2 h post-OGTT. The subjects' insulin sensitivity was estimated from fasting blood glucose and insulin using the quantitative insulin sensitivity check index (QUICKI) and in response to the OGTT using an insulin sensitivity index (ISI-Matsuda).
  

  Figure 3: Changes in fasting glucose, insulin and insulin sensitivity (QUICKI) the morning after accumulated walking, continuous walking or a rest day; values expressed rel. to sedentary control (Yap. 2015).

  Now, as you've read a few lines above, the scientists say: Only the continuous walking is beneficial. Well, I don't know about you, but if I look at the study results in Figure 1, I wouldn't say that the data suggests that only continuous brisk walking would be beneficial. In fact, the early morning glycemia, which is by the way a pretty stupid measure of glucose tolerance anyway (cortisol rises in the AM and ruins the results), is very similar and the OGTT data in Figure 2 shows no practically relevant effect or difference either.
  

  Figure 4: Glucose (a), insulin (b) and insulin sensitivity index (ISI-Matsuda) (c) calculated from an oral glucose tolerance test the morning after three 10 min bouts of accumulated brisk walking, a 30-min continuous brisk walk or resting the previous evening. Values are mean (SD) (n = 25). Main effect of time for glucose (a) and insulin (b) (both P < 0.001). Main effect of trial for ISI-Matsuda (c) with Bonferroni post hoc t tests: accumulated walking vs. continuous walking (P = 1.000); accumulated walking vs. rest (P = 0.204); continuous walking vs. rest (P = 0.081 | Yap. 2015)

  With that being said, you can still rely on your step counter as a guide to a health-relevant amount of activity. What is important is that you get your physical activity in; and not that you do it in a continuous matter (even though that may offer small benefits in the study at hand). Plus, you will remember: Especially for those with some extra-weight on their hips "Increasing Physical Activity Just as Effective as Strength, Endurance or Combined Exercise to Lose Fat and Build Muscle" | re-read the SV article.