Tyler Robbins Fitness

B.Sc. Biochemistry, Certified Strength and Conditioning Specialist (CSCS), Certified CrossFit Trainer (CCFT/CF-L3), USA Weightlifting Level 1

Filtering by Tag: Diet

Diet vs. Exercise for Weight Loss

A simple search of my blog will show you how many times I have written about this topic, but a new study published last month gives us even more insight - and confirmation, into what I have been writing about in the past.

A systematic review and meta-analysis on the effects of exercise training versus hypocaloric diet: distinct effects on body weight and visceral adipose tissue.Abstract

Exercise training ('exercise') and hypocaloric diet ('diet') are frequently prescribed for weight loss in obesity. Whilst body weight changes are commonly used to evaluate lifestyle interventions, visceral adiposity (VAT) is a more relevant and stronger predictor for morbidity and mortality. A meta-analysis was performed to assess the effects of exercise or diet on VAT (quantified by radiographic imaging). Relevant databases were searched through May 2014. One hundred seventeen studies (n = 4,815) were included. We found that both exercise and diet cause VAT loss (P < 0.0001). When comparing diet versus training, diet caused a larger weight loss (P = 0.04). In contrast, a trend was observed towards a larger VAT decrease in exercise (P = 0.08). Changes in weight and VAT showed a strong correlation after diet (R2  = 0.737, P < 0.001), and a modest correlation after exercise (R2  = 0.451, P < 0.001). In the absence of weight loss, exercise is related to 6.1% decrease in VAT, whilst diet showed virtually no change (1.1%). In conclusion, both exercise and diet reduce VAT. Despite a larger effect of diet on total body weight loss, exercise tends to have superior effects in reducing VAT. Finally, total body weight loss does not necessarily reflect changes in VAT and may represent a poor marker when evaluating benefits of lifestyle-interventions.

To summarize:

Calorie restriction (hypocaloric diet) is effective for weight loss. Exercise is effective for weight loss, although not as good as a hypocaloric diet. Hypocaloric diet and exercise in combination is effective for weight loss. Exercise is best at reducing visceral fat (adipose tissue packed in and around our organs).

So what is better for overall health?

Well, both calorie restriction and exercise are effective for improving your health in various ways, and the political answer would be that they are both effective in maintaining overall health, however what most people don't realize is that both have their strengths and weaknesses, pros and cons depending on your goals. Let me explain further.


  • For the most part, eat more than you burn to gain weight and eat less than you burn to lose weight.
  • Sure, it is possible that genetics can play a role in your metabolism and how you manage various macros (carbs, for example), but if you are gaining weight, then you are eating too much.
  • On the flip side, if you are losing weight, you are not eating enough.
  • Weight loss includes muscle loss, so by restricting calories and not resistance training you are potentially setting yourself up for strength and connective tissue loss.
  • As the above study tells us, dieting to lose weight is not as effective at removing visceral fat as exercise is. I have written about this before - "Skinny Fat" is Dangerous.
  • Losing weight too quickly (extreme calorie restriction) can cause a rebound effect known as the "Set Point Theory."
  • Protein consumption is extremely useful to maintain a healthy body weight. Make sure to increase your overall consumption as you age.


  • Most people vastly over-estimate the number of calories exercise burns. This is especially true for individuals who just "show up" to the gym and don't exercise hard enough.
  • Yes, exercise can be helpful in healthy weight management, but it is not some magical formula that can prevent obesity if you do not diet appropriately.
  • Exercise is extremely beneficial for your brain, mood, bones, connective tissues, muscles, etc. Honestly, the list is so extensive, in my opinion, nobody should go without exercise, or more specifically, a well-rounded program consisting of cardiovascular exercise and resistance training.
  • As the study above tells us, exercise is more effective then dieting alone when it comes to reducing visceral fat - fat that can raise the risk of other diseases.
  • When it comes to changing the way you look, exercise is best at it can help increase lean mass (muscle), improve the appearance of your skin/hair, improve circulation, etc.

What you eat shouldn't be so confusing!


The kinds of food that a person, animal, or community habitually eats.” (noun)

Dieting is very confusing and unfortunately, we tend to attach a negative connotation to the word, making food seem like some sort of enemy. Not only that, but our diets - i.e. what we eat, is more confusing now than at any other time in human history:

No added sugars, low fat, high fat, good fats, bad fats, soluble fibre, insoluble fibre, low calorie, electrolytes, low sodium, organic, paleo, sugar free, gluten free, high protein, low carb, Atkins, GMO, all natural, etc.

Should I keep going, or do you get the point?

There is a terrific article from Business Insider that I came across the other day titled, “What this scathing exchange between top scientists reveals about what nutritionists actually know.

I am still amazed at the number of nutritionists, diet coaches, nutrition experts, life coaches, etc. that I come across that promise results. Due to the field of work that I am involved in, I commonly get individuals asking me for diet advice. I routinely help those individuals by giving them as much information as I can for free because I know I am giving them guidance. I do not plan their diet. I do not tell them what they should or shouldn’t eat. Not because I don’t think I can help them, but because what works for one person certainly won’t work for someone else.

Don’t believe me?

A 2015 study published in the journal Cell discusses the differences in nutrition amongst a populous. Many people assume that all food products create the same physiological reactions based on their intrinsic chemical properties (i.e. nutritional content). It should make sense, right? Eating an apple or having a glass of milk should be similar from individual to individual. Well, the study fed similar meals to tens of thousands of human subjects, and found that the ingestion of these meals produced different healthy and unhealthy physiological responses from one individual to another, based on various genetic and environmental factors, such as patterns of insulin production, dietary habits, gut microbiota composition, and levels of physical activity.

The main conclusion from the study was that universal dietary recommendations have ‘limited utility’ and that, in the future, nutritional advice will have to be highly personalized in order to be effective.

The study from Cell further confirms the general theme of the article from Business Insider - there are far too many uncertainties when it comes to dietary science.

"There are a few things we are certain about," he has said. "We know that you can't live without food, and that if you eat too much, you get fat. There are certain essential nutrients - vitamins and minerals - that you need to have. You should make sure there is no lead or mercury or other toxins in your food. After that the knowledge base gets thinner and thinner."

So why all the uncertainty?

In my opinion, most self-titled coaches or experts in the diet industry do their absolute best to differentiate themselves from the crowd. Everyone has a voice, so why not be as rogue and different as possible so that you can convince individuals to come to you rather than someone else.

Not only that, but nutritional science is still very much in its infancy stage. Yes, there are things that we know, but there is a lot that we do not. It is impossible to eliminate all possible variables when it comes to dietary science, so we can only watch and view trends and patterns. We always hear news headlines that tell us one day that a food is healthy and can prevent cancer, yet another day that same food has been linked to a increased risk of cancer or some other health risk.

“The expense and logistics of randomized controlled trials leaves nutrition scientists to consider the other forms of evidence. This is where observational studies come in. In observational studies, subjects are not assigned randomly to different diets as in a traditional experiment. Instead, scientists merely record what kinds of foods each person consumes - they eat whatever they like - and then observe what happens to their health.  For example, the scientists might notice that people who eat lots of one specific food, say broccoli, get cancer more often. The scientists might then report that broccoli is "associated" with heart disease.”

So what is my point with all of this? Every person is different. How your body reacts to the nutrients you ingest may vary wildly from a friend or coworker. Don’t listen to hype about this diet trend or that, because just because one diet has been shown to be effective with someone you know by no means indicates its efficacy for you.

Inform yourself and speak to intelligent, qualified, educated individuals who can properly help point you in the right direction. Hiring or paying someone money to design a meal plan for you is not always the answer, and is more often than not just a money grab.

Finally, I always recommend individuals keep a food journal. Yes it can be tedious. Yes it can be annoying at times. But you gain such valuable information from tracking what you eat. Not only can you learn about exactly what you’re eating, but you can also reflect back upon what you ate hours and days in the past to assess your physiological outcome. For example, how was your energy level? Did you have an upset stomach? Were you bloated, gassy, and irritable? Knowledge is power, and when you can look back on what you consumed, you can better understand certain trigger foods that cause both positive and negative reactions for you.

Stay tuned, as there is plenty more interesting research to share and discuss!

Hitting a wall?

Hey TRF fans and readers, I’m back! I apologize for the nearly 7-month hiatus with my blog, but life has been busy. One of my New Year’s Resolutions, however, has been to re-kindle my interest for writing. It certainly helps when there are so many interesting studies coming out in the world of exercise physiology and nutritional sciences lately. So, over the next several weeks/months, I should hopefully be more consistent with my writing.

This blog is especially relevant to many of you readers, or perhaps for someone you know who has used the start of the new year as a reason to get back to exercising.

Have you, or someone you know, started an exercise regimen lately? Has the immediate results seemed to have slowed after a few weeks in? Well it turns out, according to a study recently published in Current Biology, that our bodies are great at adapting to stimuli that we place on it. This may either be a blessing or a curse.

Warning, incoming science jargon:

“After adjusting for body size and composition, total energy expenditure was positively correlated with physical activity, but the relationship was markedly stronger over the lower range of physical activity. For subjects in the upper range of physical activity, total energy expenditure plateaued, supporting a Constrained total energy expenditure model. Body fat percentage and activity intensity appear to modulate the metabolic response to physical activity. Models of energy balance employed in public health [ 1–3 ] should be revised to better reflect the constrained nature of total energy expenditure and the complex effects of physical activity on metabolic physiology.”

What does this mean? Well, just as our bodies adapt to stimulus like resistance training by building stronger muscles and connective tissues, we also seem to adapt to intense exercise by getting better and better at managing energy.

So, if you are not necessarily witnessing the “results” you were hoping for with exercise alone (losing weight, decreasing body fat), then increasing the amount of exercise you do, or the intensity of exercise you do may not be the answer. What this study is telling us, is that just because your work ethic has been multiplied, doesn’t mean your energy output (i.e. calories burned) has been multiplied by the same amount. Maybe the "calories in vs. calories out" isn't as accurate as we once thought.

Don’t take this an excuse to either a), cancel your gym membership, or b), work less hard in the gym, because that is not the intention of this blog at all. In fact, I am always advocating routine and intense exercise for optimal health. What I am, saying, however, is that if you are not getting the results you are looking for when it comes to weight loss or body composition, then pushing your body harder and harder isn’t necessarily the answer.