Fitness Resources

Month: February 2022

Is a Slower Metabolism Really to Blame for Middle-aged Weight Gain?

Daniel  J. Green by Daniel J. Green

We’ve all heard various versions of the same warning as we’ve gotten older:

“Just wait until you reach your 30s. You won’t be able to eat like that anymore!”

“Once you hit 40, exercise gets so much harder!”

“Once you reach your 50s, you’ll gain weight and everything will just start to hurt!”

I’m 48 years old and, to be fair, I can’t eat like that anymore, exercise is harder, I have gained weight and just about everything does hurt—and two years ahead of schedule!

However, the underlying implication of those warnings is that our metabolism is to blame and that the downward trends are all but inevitable. According to a new study, however, that does not appear to be the case.

Research recently published in the journal Science investigated daily energy expenditure throughout the human lifespan. The study was conducted by an international team of researchers, who analyzed the daily caloric expenditure of more than 6,400 people from around the world. The participants’ ages ranged from eight days to 95 years old.

While most large studies have measured basal metabolism—that is, how much energy the body uses to perform vital life-sustaining functions such as respiration and digestion—this accounts for only 50 to 70% of the calories people burn each day. This research also analyzed the energy burned to fuel all other activity, including both planned exercise and activities of daily living. Every calorie expended was accounted for, even those burned while fidgeting or thinking.

What the research team learned runs counter to a lot of the “common knowledge” around the way metabolism changes as we age.

As you might expect, energy needs skyrocket during the first year of life, as babies burn calories approximately 50% faster for their body size than adults. Interestingly, while rapid growth during this period accounts for some of that increased metabolism, the rate of calorie burn is not fully explained by the increase in weight. More research is needed to understand what else is driving the high metabolic rate during that first phase of life. After age 1, a person’s metabolism slows by about 3% per year until they reach their 20s.

Then, and here’s where things become counterintuitive, metabolism levels off and stays relatively consistent until around age 60. When body size was considered, even the growth spurt of adolescence and the changing physiology of pregnancy failed to drive an increase in metabolism. Even after age 60, metabolism declines fairly slowly, by only 0.7% per year.

Stated simply, when body mass is accounted for, metabolism remains virtually unchanged from around age 20 to age 60.

So, what’s going on here? A primary reason for the decline in metabolism is a reduction in muscle mass since muscle burns more calories than fat does. It appears that those physiological changes that take place as we pass from one decade into the next have more to do with lifestyle factors and body-composition changes than they do with a naturally slowing metabolism.

What This Means to You.

Some people may tend to throw their hands up in defeat when they think about getting older. What this research shows is that there is a lot more within their control than they might think. After all, if changes that were once perceived as an inevitable result of a slowing metabolism are actually more connected to our behaviors, then the results of this research should be a source of empowerment for clients.

Metabolism can be described as the chemical changes in living cells by which energy is provided for vital process and activities. As Carrie Myers, a certified mastery-level transformational coach with 30 years of experience in the fitness industry, points out, the fact that metabolism takes place on the cellular level means that it’s impacted by countless factors, some of which are truly out of a person’s control and others that can be positively impacted through behavior change.

Variables that are out of our control include sex, genetics and age. That leaves a seemingly endless list of variables that directly impact a person’s metabolism that health coaches and exercise professionals can address with clients, including not only nutritional intake and physical activity, but also stress, sleep, rest, mental health and the client’s overall happiness.  

Myers explains that this holistic approach addresses the whole person. “All of these elements are intertwined,” she says, “so it’s important to look at the big picture of overall health.”

Pete McCall, faculty in the Exercise Science Department at Mesa College, ACE Certified Personal Trainer and author of Ageless Intensity: High-intensity Workouts to Slow the Aging Process and Smarter Workouts: The Science of Exercise Made Simple, agrees with this approach, and says that communication is vital. While conversations about goal setting may not directly touch on a client’s metabolism, health coaches and exercise professionals should discuss the interconnectedness among the variables just described. Yes, energy intake and energy expenditure should be centerpieces of this conversation, but an understanding of the other factors is vital, as well. For example, stress management (or stress mastery, as Myers calls it) and sleep quality are both linked to hormone production, which is directly linked to metabolism.

Education can be empowering, so be sure to take advantage of the goal-setting process and conversations during your sessions with clients to emphasize the importance of overall well-being and the way in which the various elements of physical and mental health are intertwined and impact the way we age.

In Conclusion

Often we believe that weight gain and declining health are just part of the aging process. “They have been led to believe that this is natural and inevitable,” explains Myers. And, on some level this is true, but it’s not due to a rapidly slowing metabolism over the course of our lives. Instead, it occurs primarily because people simply move less as they age.

It’s a vicious cycle and a self-fulfilling prophecy. People begin to gain weight or have some aches and pains, believe it’s part of growing older, so they move less because they think physical activity will exacerbate their pain or is a fruitless pursuit, which means they gain more weight and begin to feel worse.

Take a moment to think about the older people in your life. Some are probably relatively happy and healthy, while others are battling multiple health conditions and struggling to get through the day. McCall and Myers both suggest that health coaches and exercise professionals help their clients recognize the connection between lifestyle and overall well-being, including brain health, functional independence and emotional and mental health. The intention here is not to imply that physical activity and better nutrition are cure-alls, but instead to help clients feel empowered by the fact that their behavior can have a larger impact on their quality of life than they may have previously understood.

Myers says it’s up to health coaches and exercise professionals to help their clients clarify a vision of what they would like their lives to be like as they grow older, and then ask, “How can you establish goals to set you up for that life?”

For McCall, it all comes down to two things: “Stay active and stay strong.” If you do that, a lot of the other elements fall into place, he explains. Performing physical activity, particularly resistance training, can work wonders when it comes to countering the effects of aging and the reductions in muscle mass that accompany it. Stated simply, metabolism is directly linked to muscle mass, so maintaining or even building muscle as we age can help minimize or delay the deleterious effects of the aging process, which for many people is the ultimate goal.

Calories in vs. out? Or Hormones? The debate is finally over. Here’s who

This article is from our friends over at Precision Nutrition and is republished here with their permission. Check out the Precision Nutrition course!

“You’re either with me, or you’re against me.”

This kind of binary mindset does fuel plenty of heated debates. Especially when it comes to one topic in particular: “calories in vs. calories out,” or CICO.

CICO is an easy way of saying:

  • When you take in more energy than you burn, you gain weight.
  • When you take in less energy than you burn, you lose weight.

This is a fundamental concept in body-weight regulation, and about as close to scientific fact as we can get.

Then why is CICO the source of so much disagreement?

It’s all about the extremes. At one end of the debate, there’s a group who believes CICO is straightforward. If you aren’t losing weight, the reason is simple: You’re either eating too many calories, or not moving enough, or both. Just eat less and move more.

At the other end is a group who believes CICO is broken (or even a complete myth). These critics say it doesn’t account for hormone imbalances, insulin resistance, polycystic ovary syndrome (PCOS), and other health problems that affect metabolism. Some also claim that certain diets and foods provide a “metabolic advantage” that helps people lose weight without worrying about CICO.

Neither viewpoint is completely wrong. But neither is completely right, either. Whether you’re a health and exercise professional tasked with helping clients manage their weight—or trying to learn how to do that for yourself—adopting an extreme position on this topic is problematic; it prevents you from seeing the bigger picture.

This article adds some nuance to the debate.

I’ll start by clearing up some misconceptions about CICO, and then explore several real-world examples showing how extreme views can hold folks back.

Rethinking Common Misconceptions

Much of the CICO debate—as with many other debates—stems from misconceptions, oversimplifications and a failure (by both sides) to find a shared understanding of concepts. Let’s start by getting everyone on the same page.

CICO goes beyond food and exercise.

There’s an important distinction to be made between CICO and “eat less, move more,” but some tend to conflate the two.

“Eat less, move more” only considers the calories you eat and the calories you burn through exercise and other daily movement. But CICO is really an informal way of expressing the Energy Balance Equation, which is far more involved.

The Energy Balance Equation—and therefore CICO—includes all the complex inner workings of the body, as well as the external factors that ultimately impact “calories in” and “calories out.”

Imperative to this, and often overlooked, is your brain. It’s constantly monitoring and controlling CICO. Think of it as mission control, sending and receiving messages that involve your gut, hormones, organs, muscles, bones, fat cells, external stimuli (and more) to help balance “energy in” and “energy out.”

It’s a complicated—and beautiful—system. Yet the Energy Balance Equation itself looks really simple:

[Energy in] – [Energy out] = Changes in body stores*

  • Body stores refers to all the tissues available for breakdown, such as fat, muscle, organ and bone. I purposely haven’t used “change in body weight” here because I want to exclude water weight, which can change body weight independent of energy balance. In other words, water is a confusing, confounding variable that tricks people into thinking energy balance is broken when it’s not.

With this equation, “energy in” and “energy out” aren’t just calories from food and exercise. As you can see in the illustration below, all kinds of factors influence these two variables.

When you view CICO through this lens—by zooming out for a wider perspective—you can see boiling it down to “eat less, move more” is a significant oversimplification.

Calorie calculators and CICO aren’t the same

Many people use calorie calculators to estimate their energy needs and to approximate how many calories they’ve eaten. But these tools don’t always work. As a result, people start to question whether CICO is broken. The keywords here are “estimate” and “approximate” because calorie calculators aren’t necessarily accurate.

For starters, they provide an output based on averages and can be off by as much as 20 to 30% in normal, young, healthy people. They may vary even more in older, clinical or individuals with obesity.

And that’s just on the “energy out” side. The number of calories you eat—or your “energy in”—is also just an estimate. For example, the FDA allows inaccuracies of up to 20% on label calorie counts, and research shows restaurant nutrition information can be off by 100-300 calories per food item.

What’s more, even if you were able to accurately weigh and measure every morsel you eat, you still wouldn’t have an exact “calories in” number because there are other confounding factors, such as:

  • We don’t absorb all the calories we consume, and absorption rates vary across food types. (
  • We all absorb calories uniquely based on our individual gut bacteria.
  • Cooking, blending or chopping food generally makes more calories available for absorption than may appear on a nutrition label.

Of course, this doesn’t mean CICO doesn’t work. It only means the tools we use to estimate “calories in” and “calories out” are limited.

To be crystal clear: Calorie calculators can still be very helpful for some people, but it’s important to be aware of their limitations. If you’re going to use one, do so as a rough starting point, not a definitive “answer.”

CICO doesn’t require calorie counting.

At Precision Nutrition, sometimes we use calorie counting to help clients improve their food intake. Other times we use hand portions. And other times we use more intuitive approaches.

For example, let’s say a client wants to lose weight, but they’re not seeing the results they want. If they’re counting calories or using hand portions, we might use those numbers as a reference to further reduce the amount of food they’re eating. But we also might encourage them to use other techniques, such as eating slowly or until they’re 80% full.

In every case—whether we’re talking numbers or not—we’re manipulating “energy in.” Sometimes directly and sometimes indirectly. So, make no mistake: Even when we’re not “counting calories,” CICO still applies.

CICO might sound simple, but it’s not.

There’s no getting around it: If you (or a client) aren’t losing weight, you either need to decrease “energy in” or increase “energy out.” But as you’ve already seen, that may involve far more than just pushing away your plate or spending more time at the gym.

For instance, it may require you to:

  • Get more high-quality sleep to better regulate hunger hormones, improve recovery and increase metabolic output.
  • Try stress resilience techniques like meditationdeep breathing and spending time in nature.
  • Increase your daily non-exercise movement by 
  • Trade some high-intensity exercise for lower-intensity activities to aid recovery and reduce systemic stress.
  • Improve the quality of what you’re eating, as opposed to reducing the quantity. This can allow you to eat more food with fewer total calories.
  • Tinker with the macronutrient makeup of what you eat. For example: eating more protein and fiber, or increasing carbs and lowering fats, or vice versa.
  • Experiment with the frequency and timing of your meals and snacks, based on personal preferences and appetite cues.
  • Consider temporarily tracking your food intake—via hand portions or weighing/measuring—to ensure you’re eating what you think you’re eating (as closely as reasonably possible).
  • Evaluate and correct nutritional deficiencies, for more energy during workouts (and in everyday life).
  • Consult with your physician or specialists if consistent lifestyle changes aren’t moving the needle.

Sometimes the solutions are obvious; sometimes they aren’t. But with CICO, the answers are there, if you keep your mind open and examine every factor.

Imagine yourself as a “calorie conductor” who oversees and fine-tunes many actions to create metabolic harmony. You’re looking for anything that could be out of sync. This takes lots of practice.

To help, here are five common energy balance dilemmas. In each case, it might be tempting to assume CICO doesn’t apply, but look a little deeper, and you’ll see the principles of CICO are always present.

5 Common Energy Balance Dilemmas

Dilemma #1: “I’ve been eating the same way forever, but suddenly I started gaining weight.”

Can you guess what happened?

More than likely, “energy in” or “energy out” did change, but in a way that felt out of control or unnoticeable.

The culprit could be:

  • Slight increases in food intake, due to changes in mood, hunger, or stress
  • An increase in the amount of energy absorbed—caused by new medication, an unknown medical condition or a history of chronic dieting
  • Physiological changes that resulted in fewer calories burned during exercise and at rest
  • The onset of chronic pain, provoking a dramatic decrease in non-exercise activity thermogenesis (NEAT)
  • Significant changes to sleep quality and/or quantity, impacting metabolic output and/or food consumed

In all these cases, CICO is still valid. Energy balance just shifted in subtle ways, due to lifestyle and health status changes, making it hard to recognize.

Dilemma #2: “My hormones are wreaking havoc on my metabolism, and I can’t stop gaining weight. Help!”

Hormones seem like a logical scapegoat for weight changes.

And while they’re probably not to blame as often as people think, hormones are intricately entwined with energy balance.

Even so, they don’t operate independently of energy balance. People gain weight because their hormones are impacting their energy balance, which often happens during menopause or when thyroid hormone levels decline.

For example, triiodothyronine (T3) and thyroxine (T4) are two thyroid hormones that are incredibly important for metabolic function. If levels of these hormones diminish, weight gain may occur. But this doesn’t negate CICO: Your hormones are simply influencing “energy out.”

This may seem a bit like splitting hairs, but it’s an important connection to make, whether we’re talking about menopause or thyroid problems or insulin resistance or other hormonal issues.

Understanding that CICO is the true determinant of weight loss means that you have many more tools for achieving the outcome you want.

Suppose you’re working from the false premise that hormones are the only thing that matters. This can lead to increasingly unhelpful decisions, such as spending a large sum of money on unnecessary supplements or adhering to an overly restrictive diet that backfires in the long run.

Instead, you know results are dependent on the fact that “energy in” or “energy out” has changed. Now, this change can be due to hormones, and if so, you’ll have to adjust your eating, exercise and/or lifestyle habits to account for it. (This could include taking medication prescribed by your doctor, if appropriate.)

Research suggests people with mild (10-15% of the population) to moderate hypothyroidism (2-3%) may experience a metabolic slowdown of 140 to 360 calories a day. This amount can be enough to lead to weight gain or make it harder to lose weight. (One caveat: Mild hypothyroidism can be so mild many people don’t experience a significant shift in metabolic activity, making it a non-issue.)

What’s more, women suffering from polycystic ovary syndrome, or PCOS (about 5-10%), and those going through menopause may also experience hormonal changes that disrupt energy balance.

It’s important to understand your (or your client’s) health status, as that will provide valuable information about the unique challenges involved and how you should proceed.

Dilemma #3: “I’m only eating 1,000 calories a day and I’m still not losing weight!”

So what gives? The conclusion most people jump to: Their metabolism is broken. They’re broken. And CICO is broken.

But here’s the deal: Metabolic damage isn’t really a thing. Even though it may seem that way.

While an energy balance challenge could be related to a hormonal issue, as discussed above, when someone’s eating 1,000 calories a day but not losing weight, it’s usually due to one of the two reasons that follow.

(No matter how simple they sound, this is what we’ve seen repeatedly in our coaching program, with more than 100,000 clients.)

Reason #1: People often underestimate their calorie intake

It’s easy to miscalculate how much you’re eating, as it’s usually unintentional. The most typical ways people do it:

  • They underestimate portions. (For example, without precisely measuring “one tablespoon of peanut butter,” it might be two, which adds 90 calories each time you do it.)
  • They don’t track bites, licks and tastes of calorie-dense foods. (For example, your kid’s leftover mac and cheese could easily add 100 calories.)
  • They don’t record everything in the moment and forget to log it later.
  • They “forget” to count foods they’d wished they hadn’t eaten.

A landmark study, and repeated follow-up studies, have found people often underestimate how much they eat over the course of a day, sometimes by more than 1,000 calories.

I’m not suggesting it’s impossible to be realistic about portion sizes, but if you (or your clients) aren’t seeing results on a low-calorie diet, it’s worth considering that underestimation may be the problem.

Reason #2: People overeat on the weekends

Workweeks can be stressful and when Friday night rolls around, people put their guard down and let loose. (You probably can’t relate, but just try, O.K.?)

Here’s how it goes: Let’s say a person is eating 1,500 calories a day on weekdays, which would give them an approximate 500-calorie deficit.

But on the weekends, they deviate from their plan just a little:

  • Drinks with friends and a few slices of late-night pizza on Friday
  • An extra big lunch after a workout on Saturday
  • Brunch on Sunday (“Hey, it’s breakfast and lunch, so I can eat double!)

The final tally: An extra 4,000 calories consumed between Friday night and Sunday afternoon. They’ve effectively canceled out their weekday deficit, bumping their average daily calories to 2,071.

The upshot: If you (or your client) have slashed your calories dramatically, but aren’t seeing the expected results, look for the small slips. It’s like being a metabolic detective who’s following—perhaps literally—the breadcrumbs.

By the way, if downtime is a problem for you (or a client), here’s the remedy: 5 surprising strategies to ditch weekend overeating.

Dilemma #4: “I’m eating as much as I want and still losing weight, so this diet is better than all the others!”

This might be the top reason some people reject CICO. Say someone switches from a diet of mostly processed foods to one made up of mostly whole, plant-based foods. They might find they can eat as much food as they want, yet the pounds still melt away. People often believe this is due to the “power of plants.”

Yes, plants are great, but this doesn’t disprove energy balance. Because plant foods have a very low energy density, you can eat a lot of them and still be in a calorie deficit. Especially if your previous intake was filled with lots of processed, hyper palatable “indulgent foods.”

It feels like you’re eating much more food than ever before—and, in fact, you really might be. On top of that, you might also feel more satiated because of the volume, fiber, and water content of the plants. All of which is great, but it doesn’t negate CICO.

Or take the ketogenic diet, for example. Here, someone might have a similar experience of “eating as much as they want” and still losing weight, but instead of plant foods, they’re eating meat, cheese and eggs. Those aren’t low-calorie foods, and they don’t have much fiber, either. As a result, plenty of low-carb advocates claim keto offers a “metabolic advantage” over other diets.

Here’s what’s most likely happening:

  • A greater intake of protein increases satiety and reduces appetite.
  • Limited food choices have cut out hundreds of highly processed calories they might have eaten otherwise.
  • Reduced food options can also lead to “sensory-specific satiety,” which means that when you eat the same foods all the time, they may become less appealing, so you’re not driven to eat as much.
  • Liquid calories—soda, juice, even milk—are generally off-limits, so a greater proportion of calories are consumed from solid foods, which are more filling.
  • Higher blood levels of ketones, which rise when carbs are restricted, seem to suppress appetite.

For these reasons, people tend to eat fewer calories and feel less hungry.

Although it might seem magical, the keto diet results in weight loss by regulating “energy in” through a variety of ways.

You might ask: If plant-based and keto diets work so well, why should anyone care if it’s because of CICO, or for some other reason?

Depending on the person—food preferences, lifestyle, activity level, and so on—many diets, including plant-based and keto, aren’t sustainable long-term. This is particularly true of the more restrictive approaches.

And if you (or your client) believe there’s only one “best diet,” you may become frustrated if you aren’t able to stick to it. You may view yourself as a failure and decide you lack the discipline to lose weight. You may even think you should stop trying. None of which are true.

Your results aren’t diet dependent. They’re behavior dependent.

Maintaining a healthy body (including a healthy body weight) is about developing consistent, sustainable daily habits that help you positively impact “energy in” and “energy out.”

This might be accomplished while enjoying the foods you love, by:

  • Eating until you’re 80% full
  • Eating slowly and mindfully
  • Eating more minimally processed foods
  • Getting more high-quality sleep
  • Taking steps to reduce stress and build resilience

It’s about viewing CICO from 30,000 feet and figuring out what approach feels sane—and achievable—for you.

Sure, that might include a plant-based or keto diet, but it absolutely might not, too. And you can get great results either way.

Dilemma #5: “I want to gain weight, but no matter how much I eat, I can’t seem to.”

The CICO conversation doesn’t always revolve around weight loss. Some people struggle to gain weight, especially younger athletes and people who are very active at work (think: jobs that involve manual labor).

It also happens with those who are trying to regain lost weight after an illness.

When someone intentionally eats more food but can’t pack on the pounds, it may seem like CICO is invalidated, but here’s what our coaches have found:

People tend to remember extremes.

Someone might have had six meals in one day, eating as much as they felt like they could stand, but the following day, they only ate two meals because they were still so full. Maybe they were busy, too, so they didn’t even think much about it. The first day—the one where they stuffed themselves—would likely stand out a lot more than the day they ate in accordance with their hunger levels. That’s just human nature.

It’s easy to see how CICO is involved here. It’s a lack of consistency on the “energy in” part of the equation.

One solution: Instead of stuffing yourself with 3,000 calories one day, and then eating 1,500 the next, aim for a calorie intake just above the middle that you can stick with, and increase it in small amounts over time, if needed.

People often increase activity when they increase calories.

When some people suddenly have more available energy—from eating more food—they’re more likely to do things that increase their energy out, such as taking the stairs, pacing while on the phone and fidgeting in their seats.

They might even push harder during a workout than they would normally. This can be both subconscious and subtle.

And though it might sound weird, our coaches have identified this as a legitimate problem for “hard gainers.”

Your charge: Take notice of all your activity. If you can’t curtail some of it, you may have to compensate by eating even more food. Nutrient- and calorie-dense foods such as nut butters, whole grains and oils can help, especially if you’re challenged by a lack of appetite.

3 Strategies to Game the System

Once you accept that CICO is both complex and inescapable, you may find yourself up against one very common challenge, namely: “I can’t eat any less than I am now!” This is one of the top reasons people abandon their weight-loss efforts or go searching in vain for a miracle diet.

Here are three simple strategies you (or your clients) can use to create a caloric deficit, even if it seems impossible. It’s all about figuring out which one works best for you.

Maximize protein and fiber

Consuming higher amounts of protein increases satiety, helping you feel more satisfied between meals. And consuming higher amounts of fiber increases satiation, helping you feel more satisfied during meals. These are both proven in research and practice to help you feel more satisfied overall while eating fewer calories, leading to easier fat loss.

While the advice to eat more protein and fiber may sound trite, most people trying to lose weight still aren’t focused on getting plenty of these two nutrients.

And you know what? It’s not their fault. When it comes to diets, almost everyone has been told to subtract, to take away the “bad” stuff and only eat the “good” stuff.

But there’s another approach: Just start by adding. If you make a concerted effort to increase protein (especially lean protein) and fiber intake (especially from vegetables), you’ll feel more satisfied. You’ll also be less tempted by all the foods you think you should be avoiding, which helps to automatically “crowd out” ultra-processed foods.

Which leads to another big benefit: By eating more whole foods and fewer of the processed kind, you’re actually retraining your brain to desire those indulgent, ultra-processed foods less.

That’s when a cool thing happens: You start eating fewer calories without actively trying to—rather than purposely restricting because you have to. This makes weight loss easier.

Starting is simple: For protein, add one palm-sized portion of relatively lean protein—chicken, fish, tempeh—to one meal. This is beyond what you would have had otherwise. Or have a Super Shake as a meal or snack.

For fiber, add one serving of high-fiber food, such as vegetables, fruit, lentils and beans, to your regular intake. This might mean having an apple for a snack, including a fistful of roasted carrots at dinner, or tossing in a handful of spinach in your Super Shake.

Try this for two weeks, and then add another palm of lean protein, and one more serving of high-fiber foods.

In addition to all the upside we’ve discussed so far, there’s also this: Coming to the table with a mindset of abundance—rather than scarcity—can help you avoid those anxious, frustrated feelings that often come with being deprived of the foods you love. So instead of saying, “Ugh, I really don’t think I can give up my nightly wine and chocolate habit,” you might say, “Hey, look at all this delicious, healthy food I can feed my body!”

(And by the way, you don’t have to give up your wine and chocolate habit, at least not to initiate progress.)

Shift your perspective

Imagine you’re on vacation and you slept in and missed breakfast. Of course, you don’t really mind because you’re relaxed and having a great time. And there’s no reason to panic: Lunch will happen.

But since you’ve removed a meal, you end up eating a few hundred calories less than normal for the day, effectively creating a deficit. Given that you’re in an environment where you feel calm and happy, you hardly even notice.

Now suppose you wake up on a regular day, and you’re actively trying to lose weight. You might think: “I only get to have my 400-calorie breakfast, and it’s not enough food. This is the worst. I’m going to be so hungry all day!” You head to work feeling stressed, counting down the minutes to your next snack or meal. Maybe you even start to feel deprived and miserable.

Here’s the thing: You were in a calorie deficit both days, but your subjective experience of each was completely different.

What if you could adjust your thinking to be more like the first scenario rather than the second?

Of course, I’m not suggesting you skip breakfast everyday (unless that’s just your preference). But if you can manage to see eating less as something you happen to be doing— rather than something you must do—it may end up feeling a lot less terrible.

Add activity rather than subtracting calories

Are you a person who doesn’t want to eat less, but would happily move more? If so, you might be able to take advantage of something I’ve called G-Flux.

G-Flux, also known as “energy flux,” is the total amount of energy that flows in and out of a system.

As an example, say you want to create a 500-calorie deficit. That could look like this:

  • Energy in: 2,000 calories
  • Energy out: 2,500 calories
  • Deficit: 500 calories

But it could also look like this:

  • Energy in: 3,000 calories
  • Energy out: 3,500 calories
  • Deficit: 500 calories

In both scenarios, you’ve achieved a 500-calorie deficit, but the second allows you to eat a lot more food. That’s one benefit of a greater G-Flux.

But there’s also another: Research suggests if you’re eating food from high-quality sources and doing a variety of workouts—strength training, conditioning and recovery work—eating more calories can help you carry more lean mass and less fat because the increased exercise doesn’t just serve to boost your “energy out.” It also changes nutrient partitioning, sending more calories toward muscle growth and fewer to your fat cells.

Plus, since you’re eating more food, you have more opportunity to get the quantities of vitamins, minerals and phytonutrients you need to feel your best.

To be clear, this is a somewhat advanced method. And because metabolism and energy balance are dynamic in nature, the effectiveness of this method may vary from person to person. Plus, not everyone has the ability or the desire to spend more time exercising. And that’s O.K.

By being flexible with your thinking—and willing to experiment with different ways of influencing CICO—you can find your own personal strategy for tipping energy balance in your (or your clients’) favor.

Bio – intervention—Making Your Health Span Match Your Life Span

Mark Mayes – Certified Exercise Physiologist

Ponce de León supposedly searched for it in the New World. Herodotus thought it might be near Ethiopia. People have sought a fountain of youth for centuries. Disappointed by the fruitless search for a miraculous pool that could rejuvenate them, people turned instead to elixirs, creams, and cell-rejuvenating drugs—anything that offered glimmer of hope for retaining youth. No one yet has discovered a magic formula that can guarantee a never-ending life span. Diet and exercise researchers, however, have made significant progress discovering ways to extend one’s health span and, thereby, one’s life span.

    William Evans, Ph.D. and other researchers from the U.S. Department of Agriculture’s Human Nutrition Research Center on Aging at Tufts University (HNRCA) have identified ten biomarkers that may slow down the aging process. “Advanced age is not a static, irreversible biological condition of unwavering decrepitude,” Dr. Evans says. “Rather, it’s a dynamic state that, in most people, can be changed for the better no matter how many years they’ve lived or neglected their body in the past” (14–15). Evans and his colleagues at the HNRCA have outlined the following ten biomarkers of vitality that they believe we can alter through exercise and proper nutrition: muscle mass, strength, basal metabolic rate, body fat percentage, aerobic capacity, cholesterol/HDL ratio, blood/sugar tolerance, blood pressure, bone density and regulation of internal body temperature.

    Vital to extending one’s health span, according to Evans, is to concentrate on building muscle while decreasing fat. “Losing weight is the wrong goal,” he points out. “You should forget about your weight and, instead, concentrate on shedding fat and gaining muscle”. One might ask in reply, “I’m 65 years old, and I weigh much the same as I did when I was 21. How would increasing my muscle mass improve or extend my life?” As we get older, we lose muscle tissue at a rate of about 6.6 pounds per decade, and we tend to replace this lost muscle tissue with fat.

Muscle mass, Evans first biomarker, is a key component to other biological functions and in some way, affects the other nine biomarkers. A strong and toned musculature contributes to overall well-being, especially for older adults. Evans and other researchers have found that an increase in musculature:

  • increases the body’s metabolism, thus enabling one to burn more calories, which, in turn, helps decrease body fat.
  • increases one’s aerobic capacity because denser muscles require additional oxygen; an increased aerobic capacity allows one to be more active.
  • increases the body’s ability to utilize insulin, which decreases the chance of developing diabetes later in life.
  • helps one maintain a high level of HDL cholesterol— “good cholesterol”—in the blood.
  • adds to bone density because strength training and other exercises that increase musculature also stress bones, causing them to become harder.

Many researchers believe that old age is not a time to relax and become idle. Many of the diseases and much of the deterioration that we see in our bodies during our senior years can be prevented or mitigated through exercise. Improvements in Evans’s second biomarker, strength, provide abundant examples.

    Among many misconceptions concerning the bodies of older adults are that they cannot improve their strength or that they should not stress their muscles the way that a younger person does. Studies reveal that between the ages of 20 and 70, we lose almost 30 percent of our muscle cells due to inactivity. But research at Tufts has shown that a decline in muscle strength and size is not inevitable. Through strength training, a 70-year-old male could regain the strength of a 20-year-old sedentary male.

    Another misconception is that with old age comes an increased likelihood of falling. Evans, however, has demonstrated that the increased incidence of falls in seniors is caused by a decrease in muscle tissue and strength in the legs. Falling in one’s senior years is not due to age but rather to a sedentary lifestyle and a lack of exercise!

Our body’s ability to shed fat and burn calories at rest is called basal metabolic rate (BMR), Evans’ third biomarker. BRM is an indicator of how efficiently our bodies break down tissue and release energy so we can perform daily functions. However, if we take in more fuel (calories) than our bodies can use given our BMR, those calories are stored as fat. After age 20, our BMR drops by about two percent every decade. But studies have shown that no matter what our age, through exercise and increased muscle mass we can stop this decline and even restore our BMR and our ability to burn calories.

The fourth biomarker, percentage of body fat, is directly related to increased disease in older individuals. Excess body fat places an added stress on the heart and increases the chance of stroke and diabetes. Seniors have the ability to lose fat weight—the same as a younger person—through diet and exercise.

Aerobic capacity is Evans’ fifth biomarker. It describes the body’s ability to move large amounts of oxygen through the bloodstream to tissue in a given amount of time, a process that depends on a good cardiopulmonary system—the heart, lungs, and circulatory mechanisms. It is true that aerobic capacity declines 30 to 40 percent by age 65. However, the decline is less pronounced in individuals who exercise regularly. Evans believes that inactivity in seniors reduces the muscles’ oxidative capacity and causes the muscular fatigue that many aging people experience. Exercise physiologists have shown that seniors who start to exercise make greater improvements to their aerobic capacity than younger adults. Certainly, older adults who have been inactive and then begin to exercise have much more room to improve, but it’s important to note that drastic improvements to aerobic capacity can be made even in advancing years.

Everything in the supermarket these days seems to claim to be cholesterol-free; cholesterol is Evans sixth biomarker, but what is it? Cholesterol is a fatty substance produced by the body that is a necessary component in cell membranes and certain sex hormones. It circulates in the bloodstream and is associated with a protein called lipoprotein. There are several types of cholesterol that we need to be concerned with: HDL, LDL, and VLDL. HDL is known as “good cholesterol” because it helps remove plaque or LDL from the arteries. LDL and VLDL are known as “bad cholesterol” because in excess, they can cause a narrowing of blood vessels. As with the other biomarkers, several factors influence our control over cholesterol: genetic make-up, a lack of exercise, obesity, and diet. All but one of these components can be altered through lifestyle changes—we have little control over genetics.

    If the body produces too much cholesterol or if one’s diet is high in cholesterol, lipoproteins can start to collect in the body tissue. “Atherosclerosis” is a condition in which excess lipoproteins collect in the blood vessels, and it can eventually develop into heart disease and other circulatory problems. Since the body produces its own cholesterol, it is NOT important that we include it in our diet, but we should be concerned about consuming foods with too much of it. LDL and VLDL levels can be lowered through changes to our diet, but according to the latest studies, HDL can only be increased by lowering body fat and through exercise.

The body’s ability to control blood sugar is the seventh biomarker. With advancing age, the body’s ability to take up and utilize blood sugar decreases. This, in turn, causes the sugar level in our blood to rise, which can develop into mature-onset diabetes, also known as “type 2 diabetes.” By age 70, 20 percent of men and 30 percent of women have an abnormally high blood sugar level. Researchers have found that a decline in sugar tolerance is due to a decrease in the activity level of older adults, an increase in body fat and reduced muscle mass, which leads to a reduction in the body’s ability to absorb insulin. The body produces insulin to regulate the level of sugar in the blood; insulin causes the muscles to use the sugar for energy. The bodies of older adults cannot absorb insulin as readily because their muscle mass has been reduced as they have aged. This lack of muscle mass also continues the cycle of fat storage; excess sugar in the blood that is not used over time is converted to body fat. Age, however, has been shown NOY to decrease one’s ability to influence blood sugar.

Blood pressure is Evans’ eighth biomarker. Increased blood pressure is caused primarily by obesity; smoking; a high-fat, high-salt diet and a lack of exercise. Heredity and race do have some effect on blood pressure, but even considering risk factors beyond our control, blood pressure can be controlled with medication, diet and exercise. High blood pressure, or hypertension, does not have to be a limiting factor for the older person. Scientists at Copper’s Clinic for Aerobic Research in Dallas found that people who maintained their fitness level had a 34 percent lower risk of developing hypertension.

Bone density, the ninth biomarker, is, in part, affected by hormonal changes in women, poor eating habits, deficient calcium absorption and a sedentary lifestyle. Research has shown that an individual’s bone loss is about one percent per year. “Osteoporosis” is a substantial bone loss that increases the risk of bone fractures. Osteoporosis is associated with growing old, but, Evans argues, “Osteoporosis is not a necessary or normal component of aging”. The loss of bone density can be influenced by diet and exercise. Researchers at Tufts found that women who exercise have a higher level of Vitamin D, which aids in the absorption of calcium. They also found that weight-bearing exercises that continually apply stress to the bone cause the bone to become harder. Research to date has not concluded that an increase in calcium intake prevents or slows the effects of bone loss. Tufts researchers combined high-calcium intake with exercise in their study and found that only exercise affected bone loss.

Biomarker ten is the body’s ability to regulate its internal temperature. The body has its own built-in thermostat, but the effects of aging can impair this control mechanism. In a typical older adult, cardiac output, including blood flow to the skin, is reduced. This diminished blood flow to the skin makes sweating harder for the older person’s body because blood flow brings heat to the skin, causing the body to sweat and release that heat. When the body cannot sweat, it cannot release heat as effectively, so it’s internal temperature rises. On the other hand, shivering, which is the body’s way to produce heat, is also decreased in older adults—primarily due to a loss in muscle mass. An inability to shiver makes it more difficult for an older person’s body to raise its internal temperature.

The older adult who stay in shape is better equipped to keep his or her body’s internal temperature at a safe level through increased blood flow to the skin and through an improved BMR.

Unfortunately for us, Herodotus and Ponce de León’s searches were in vain.

There is no magic formula to slow the aging process. The latest research shows, however, that it is possible to close the gap between one’s health span and one’s life span through regular exercise and proper nutrition. Dr. Evans’ ten biomarkers map it all out for us.

Mark Mayes founded Fitness Resources in 1991 and has over 30 years in the fitness industry. He is certified by the (ACSM) American College of Sports Medicine as Exercise Physiologist and ACSM for Seniors. Mayes works with individuals who wish to improve their health and fitness levels.

Reference: William Evans, Ph. D., and Irwin H. Rosenberg, M.D., Biomarkers: The 10 Determinates of Aging You Can Control, (New York: Simon & Schuster, 1991).

Do Certain Carbs Cause Overweight and Obesity? Hormonal changes may be the culprit.

A team of 17 internationally recognized scientists published a paper in The American Journal of Clinical Nutrition, supported by more than 169 journal references, proposing that the obesity epidemic in America is not caused just by consuming too many calories (i.e., overeating). Instead, they reckon that overweight and obesity are caused primarily by hormonal changes brought on by eating refined carbohydrates and sugar-added foods.

These foods cause a high rise in blood sugar that increases hormone insulin secretion of the hormone insulin which, in turn, causes changes in metabolism that signal fat cells to store more calories. This leaves fewer calories available to fuel muscles and other metabolically active tissues like the brain and heart. The brain perceives that the body isn’t getting enough energy, which, in turn, leads to feelings of hunger.

This challenges the “energy balance model,” which says weight gain occurs because individuals consume more energy than they expend. And perhaps why public health messaging exhorting people to eat less and exercise more has failed to stem rising rates of overweight and obesity, as well as related diseases.

Do you agree that there is some merit to this carbohydrate-insulin model for obesity? Does focusing on what we eat rather than how much we eat a better strategy for weight management? Are you in the camp that calories-in, calories-out, is still a leading player in body weight? Does this paper fail to recognize dietary fat as a leading cause of weight gain in Americans? Send your answers to Sandy Todd Webster at

Hormonal changes may be the culprit.

Plant Protein for Muscle Growth

Plant protein can be just as effective as animal protein for muscle gain.

Matthew Kadey, MS, RD
Jul 7, 2021

We need two things to build muscle: resistance training and dietary protein. It’s long been thought that protein from animals is superior for building bigger, stronger muscles than plant protein. But new data shows that when it comes to making muscle, a steady high-protein, plant-only diet appears to work just as well.

In the study, published in Sports Medicine, long-time vegan and omnivore men (average age 26) participated in a 12-week resistance training program. The men received a protein supplement (soy for vegans and whey for meat eaters) in sufficient amounts to ensure that everyone consumed 1.6 grams of protein per kilogram of body weight daily from a combination of whole foods and protein powder. At the end of 3 months, both groups showed significant improvements in muscle size and strength, with no differences between vegan and omnivore lifters.

The authors concluded that as long as someone is getting the full amount of protein needed to support training, the source isn’t so important. But plant-only people may need more supplementation to get the necessary servings: The researchers noted that vegan lifters needed about 58 g a day of supplemental soy protein to get to 1.6 g, whereas lifters in the omnivore group reached that mark with just 41 g per day of more protein-dense whey.

Further research is needed on other populations, such as women and older individuals, whose muscle-building responses to specific protein sources may differ from the responses of young men.