By: Austin McNally, PT, BSc, RD, CDE, CSCS
Many people kick off their fat loss journey with fasted cardio, hours on the treadmill, or a new workout routine, hoping the pounds to start melting away. While exercise is an incredible tool for improving health and longevity, many soon realize—sometimes to their surprise—that it alone isn’t enough to achieve the fat loss they were hoping for.
So, what’s missing? Why doesn’t exercise always translate to rapid fat loss – is it a waste of time?
Exercise is definitely not a waste of time—it’s just not the magic bullet for fat loss that many people expect. While exercise offers an extraordinary array of health benefits, its direct impact on fat loss is often smaller than people anticipate. Let’s break down the biggest myths surrounding exercise and fat loss—so you can focus on what actually works.
Fat Loss Myth #1: “You Can Spot-Reduce Fat”
Localized, exercise-induced reductions in body fat is a concept that has been debated for decades, but has yet to be substantiated in exercise research. The truth is that targeted body fat reduction is in fact observed in the literature, but not to a meaningful degree. During exercise, the body doesn’t only burn fat from just one region, even when you do exercises that focus specifically on a targeted area. It is well documented and acknowledged that exercise leads to whole-body utilization and reductions in body fat.
Everyone has a unique body fat distribution pattern, which is largely determined by genetics and other individual factors. Some people naturally store more fat in certain areas, such as the abdomen, hips, and thighs – while others accumulate fat in different regions (i.e arms, lower back, face, etc.). This is why two people with the same body fat percentage can have completely different body shapes and appearances.
While situps and crunches aren’t the key to eviscerating stubborn belly fat, localized strength training does build muscle, and as the proportion of muscle to fat changes, that area will start to look more defined.
In other words, doing ab exercises won’t directly burn belly fat, but they will strengthen and grow your abdominal and core muscles, making them more prominent. Once total body fat is reduced through a sustained calorie deficit (i.e combination of exercise and nutrition), that increased muscle definition will become more visible, creating a leaner and more sculpted look.
Lesson Learned: Continue to work on strengthening specific muscles with targeted training, but don’t expect to see the results until fat is lost throughout the body.
Sources:
PubMed. “Body Fat Distribution and Exercise.” Retrieved from https://pubmed.ncbi.nlm.nih.gov/23222084/
PubMed Central. “Effects of Exercise on Fat Loss.” Retrieved from https://pmc.ncbi.nlm.nih.gov/articles/PMC10680576/
Fat Loss Myth #2: “Fasted Cardio Is the Best Way to Lose Fat”
In recent years, fasted cardio (exercising on an empty stomach), usually in the morning – has gained a great deal of traction in the media, particularly in regards to its potential to increase the rate of fat loss. It is proposed that when your body is in a fasted state, it will rely more on stored fat for energy instead of carbohydrates. During fasted cardio our body preferentially oxidizes fat for energy due to the reduced availability of carbohydrates.
The idea and mechanism is sound, but does this method actually lead to greater fat loss?
It’s important to understand that fat loss is the product of a sustained energy deficit, meaning that total calorie balance is what really matters (i.e total calorie intake vs total calorie expenditure). Which substrate we use to produce energy – whether it’s fat or carbohydrate – doesn’t have a large impact on fat loss when total intake and expenditure are equivalent. Research has shown that over the course of a day or week, there’s little to no difference in total reductions in body fat between fasted and fed cardio groups so long as total calorie intake and total calorie expenditure remain the same.
Lesson Learned: Cardio is not only great for your health, but can contribute to weight loss. The best time to do cardio is the time that works best for you in terms of consistency and effort.
Source:
PubMed Central. “Fasted Exercise and Fat Loss: An Examination.” Retrieved from https://pmc.ncbi.nlm.nih.gov/articles/PMC4242477/
Fat Loss Myth #3: “More Sweat Equals More Fat Burn”
Sweating is your body’s natural cooling system. It’s a tightly regulated process that occurs when your body senses an internal rise in temperature —whether it’s exercise induced, from hot weather, or even stress. Your body releases sweat through glands in the skin, and as the sweat evaporates, it helps cool you down and achieve a stable core temperature.
Many people associate sweating with fat loss, believing that the more they sweat during a workout, the more fat they’re burning. However, sweating does not directly correlate with fat loss.
Sweat itself is mostly water, with small amounts of electrolytes – primarily sodium, and other minerals. The amount you sweat depends on several factors, including genetics, humidity, room temperature, workout intensity, and even your individual conditioning level. What’s interesting is that ‘fitter individuals’ are often better at sweating, meaning they sweat more efficiently as their bodies have adapted to cooling down faster during periods of exercise.
While you may temporarily lose water weight when you sweat, this shouldn’t be mistaken for a net decrease in fat mass. Once hydration status is restored, that lost weight comes back. Genuine fat loss comes from a sustained, prolonged calorie deficit, not from how much you sweat during a workout.
Lesson Learned: Working up a sweat is great, but is not essential for fat loss.
Source:
PubMed Central. “Sweat and Fat Loss: What’s the Real Connection?” Retrieved from https://pmc.ncbi.nlm.nih.gov/articles/PMC8290478/
Fat Loss Myth #4: “Lifting Weights Makes You Bulky Instead of Lean”
Many people, especially women, avoid strength training out of fear that it will make them look “bulky.” This is the equivalent of avoiding driving out of fear that it will turn you into a Race Car Driver.
Building significant muscle size requires years of intense and methodical training, a surplus of calories, and specific genetic and hormonal predispositions—most of which don’t apply to the average person lifting weights for health and fitness goals.
Many women characterize their fitness goal as achieving a ‘toned body’. The term ‘toning’ is often used to describe the goal of achieving a lean, defined physique without excessive size.
However, this is a misnomer, and from a physiological standpoint, there’s no such thing as ‘toning’ a muscle—muscles can either grow (hypertrophy) or shrink (atrophy). What people typically mean by “toning” is increasing muscle definition, which is achieved by building muscle mass and reducing visible body fat. Lifting weights helps to increase your relative proportion of lean muscle mass, favourably impacting body composition and creating the appearance of a ‘toned’, or sculpted physique. Weight lifting can be a very important part of a weight loss journey as it helps to maintain muscle mass (and metabolic rate) while losing fat.
Lesson learned: Keep up with the weights! Aim for 2-3 or more sessions of weight-resistant activity per week.
Meet with Austin online to dial in to your training potential!
Fat Loss Myth #5: “You Have to Exercise for Hours to See Results”
Many people make the mistake of viewing exercise as a means to solely accomplish fat loss, but this mindset can be counterproductive. Exercising boasts a wide array of health benefits – from extending lifespan to improving body composition and biomarkers of health. Perhaps the most insignificant benefit of exercise is the resulting calorie burn.
The key to success isn’t the number of hours you put in—it’s the consistency in which it’s applied. Of course, from an energy balance perspective, longer sessions will result in more energy burned, but the resulting cost of fatigue, hunger and the risk of burnout are also amplified.
Consider this: it takes a great deal of time and effort to burn calories through exercise, whereas it requires much less effort to consume calories through our diet. If we rely solely on exercise without nutrition intervention to lose weight, we are fighting an uphill battle.
You don’t need marathon-length exercise sessions to make significant progress—short, effective workouts can be just as (if not more) beneficial, especially when combined with a structured nutrition protocol to achieve an energy deficit.
Source:
PubMed. “Exercise Duration and Fat Loss: A Review.” Retrieved from https://pubmed.ncbi.nlm.nih.gov/10610070/
Lesson Learned: While exercise is undeniably valuable and can help to accelerate fat loss, nutrition intervention should be the backbone of weight loss efforts.
Fat Loss Myth #6: “Fat-Burning Zones Are the Key to Weight Loss”
Zone training is a methodology borrowed from endurance training and has been generalized to many fitness enthusiasts and weight loss connoisseurs. The idea of a ‘fat-burning zone’ has been widely popularized, leading many to believe that working out at a lower intensity is the most effective way to lose fat.
While it’s true that lower-intensity exercise primarily uses fat as an energy source to produce fuel, this doesn’t mean it’s the best – or the only way to decrease body fat.
Zone 2 training, coined by many as the ‘fat-burning zone’, refers to an exercise intensity that brings your heart rate within a specific range—typically 50–70% of your maximum heart rate—where the body relies more on fat for energy rather than carbohydrates. This has led to the misconception that exercising at a lower intensity is more optimal for reducing body fat. However, as we previously discussed, the proportional use of fat for energy doesn’t enhance total fat loss efforts, rather it is the overall calorie balance that matters most.
Although a greater percentage of calories burned in this zone come from fat, the total number of calories burned is relatively low compared to higher-intensity workouts. For example:
- A slow-paced walk may burn 150 calories, with 70% from fat (105 calories from fat).
- A high-intensity workout may burn 400 calories, with only 40% from fat (160 calories from fat).
The chosen modality of exercise is far less important than the consistency in which it is applied. The key to success is achieving and maintaining an energy deficit, not just staying in a specific heart rate zone during exercise.
Lesson Learned: Don’t step over dollars to pick up pennies! Choose an exercise intensity that is enjoyable for you, as this is far more likely to become a consistent part of your routine and lead to long-term results.
Sources:
PubMed. “Exercise Intensity and Fat Utilization.” Retrieved from https://pubmed.ncbi.nlm.nih.gov/37497435/
PubMed Central. “Fat-Burning Zones: Fact vs Fiction.” Retrieved from https://pmc.ncbi.nlm.nih.gov/articles/PMC8290478/
Final Thoughts
While exercise is unarguably an essential component of a healthy lifestyle, it’s not the magic solution for fat loss that many people expect. Strength training, cardio, and physical activity in general all play important roles in improving body composition, increasing lifespan, and supporting long-term weight management. However, sustainable fat loss ultimately comes down to the intimate connection between nutrition and exercise.
A sustainable, personalized nutrition protocol is the most important and effective way to create a calorie deficit and achieve lasting fat loss results. The fundamental components of effective nutrition planning include:
- Behaviour & routine modifications
- Portion and calorie control strategies
- Appetite & hunger regulation
- Macronutrient management
- Meal & snack timing
- Commitment and accountability coaching
Rather than getting caught up in popularized fads—whether it’s fasted cardio, fat-burning zones, or hot room fitness classes— it is far more productive to focus on a balanced approach that combines evidence-based nutrition strategies, in combination with appropriate exercise intervention to achieve and maintain a moderate energy deficit.
At NutriProCan, we believe that exercise and nutrition go hand in hand, both playing a vital role in achieving sustainable fat loss results. As highly specialized dietitians with expertise in body composition and weight management, we provide personalized nutrition coaching to help you optimize your diet for lasting results.
Start With A Free Consult With Austin To Discuss:
- Sport & Performance Nutrition
- Nutrition for Fitness & Body Composition Goals
- Nutrition for Bodybuilding & Strength Sport
- Sustainable Weight Loss
- Geriatric Health Optimization
- Healthy Eating Habit Changes
- Chronic Disease Management (diabetes, high blood pressure and high cholesterol)
- Additional practice areas
If you are outside of Ontario, please choose another dietitian: https://nutriprocan.ca/about-us/
Austin is great at what he does
I am a client, in my mid 50’s and I am seeing results!
great article – keep it going!
Kristine
Amazing feedback Kristine – thank you!