Busting Common Fitness and Health Misconceptions

Everyone starts somewhere. In my health and fitness journey, and growing up in the 80s and 90s, I believed many fitness myths, drank up fitness culture like Kool-Aid (although, GASP!, we would never actually drink Kool-Aid if we were being healthy), and made all the same mistakes I see people making now.

But through trial and error over the years and eventually studying and understanding nutrition and fitness, I realized how wrong I was—and how many of these misconceptions hurt more than they help. Let's talk about 10 common fitness myths that I once believed, and why focusing on flexible, sustainable fitness and nutrition habits is the key to lasting success—no extremes required.

1. I Thought Sugar Was Evil (Even the Kind That Comes in Bananas and Dairy)

The misconception that sugar is inherently evil stems from misunderstanding how our bodies process carbohydrates. Natural sugars in fruits and dairy contain fiber, vitamins, minerals, and other nutrients that slow digestion and sustain energy. Sure, it's healthy to put reasonable limits on added sugars (about 30 grams per day)—those found in soda, candy, and ultra-processed foods. But bananas and dairy? They're fuel, not villains.

2. I Banished Carbs to Oblivion (Even as a Runner!)

Carbs are the body's primary energy source, especially for endurance activities like running. Glycogen, stored in your muscles and liver, comes from the carbs you eat and is your body's go-to fuel during workouts. Extremely low-carb diets can lead to fatigue, impaired performance, and even muscle loss in athletes. Instead of fearing carbs, focus on nutrient-dense sources like whole grains, fruits, and vegetables, which provide energy and essential nutrients like fiber.

Check out my YouTube video: Carbs are not the enemy: The Truth About Eating Carbs For Weightloss

3. I Thought Eating Less and Running More Was the Answer to Weight Loss

The truth is, it works... until it doesn’t. Sure, you can eat less and run more to lose weight, but is it sustainable? Is it healthy? Can you keep the weight off? For me, the answer was a resounding no. (Click here for my fat loss story).

The "calories in, calories out" equation oversimplifies the complex processes involved in weight management. A calorie deficit is essential for weight loss—we can’t defy the laws of thermodynamics. However, chronically undereating while overexercising can backfire and derail your progress. This approach may slow your metabolism, elevate stress hormone levels, and lead to muscle loss instead of fat loss, making it much harder to maintain your weight in the long run.

Sustainable fat loss occurs when you are in a calorie deficit and fuel your body correctly, allowing for efficient workouts and recovery. A mix of strength training, cardio, balanced nutrition, and adequate rest is more effective and sustainable than simply running on empty.

4. I Thought Rice Cakes and Fat-Free SnackWells Were Healthy Foods

This belief came from the low-fat craze of the '80s and '90s, which popular culture demonized fat without understanding its vital role in the body—not unlike how our current culture demonizes sugar. Fat-free or low-fat processed foods often replace fat with added sugars or artificial ingredients to improve taste. Plain low-fat dairy products are an exception—they're naturally lower in fat and usually don’t contain added sugar unless flavored or sweetened.

Whole, unprocessed foods like avocados, nuts, and seeds contain healthy fats essential for hormone production, brain health, and nutrient absorption. Modern nutrition science supports the idea that quality, not just calorie count or macro percentage, determines whether a food is healthy.

5. I Thought Organic Vegetables Were Healthier

Organic produce is grown without synthetic pesticides or fertilizers, but that doesn't necessarily mean it's more nutritious. The nutritional differences between organic and conventionally grown vegetables are minimal. What matters more is eating a wide variety of fruits and vegetables—organic or not—to get essential nutrients. Conventionally grown options are just as safe and nutritious for most people. If you want organic foods that fit your budget, that's great! But the idea that you can't eat healthy if organic isn't an option for you? That's simply not true.

6. I Thought Strength Training Would Make Me Look Manly

The idea that lifting weights makes women bulky is one of those outdated myths that just won't die. Women's bodies produce significantly less testosterone than men's, meaning we don't have the same capacity for large muscle growth. Strength training builds lean muscle mass, increases metabolism, improves bone density, and enhances strength and badassery (that’s definitely a word despite what spell check says). It's one of the most effective ways to reshape your body and support long-term health, especially as we age.

I've been trying to bulk up for years, and it is a long, slow process. I can promise it won't happen by accident, and if you do wake up one day and look more muscular than you prefer, you can change your training to reflect your new goals.

Want to get started? Grab my free full body dumbbell program here—delivered on a convenient app!

7. I Thought 1,500 Calories or Less Was The “Secret” To Weight Loss

Consuming too few calories can lead to nutrient deficiencies, hormonal imbalances, and a down-regulated metabolism. While calorie needs will vary significantly based on weight, muscle mass, and activity levels, most active adults likely require more energy to support physical activity and recovery. Instead, eat with a slight calorie deficit (if fat loss is the goal). Undereating increases cravings and the risk of binge eating, undermining long-term goals.

8. I Thought Skipping Rest Days Meant I Was More Hardcore and Committed

Rest days are when your body repairs and rebuilds itself. If you skip rest days, you are skipping fitness gains. You get fitter and faster and build muscle in the rest period and while you sleep. Overtraining, or under recovering, can lead to fatigue, decreased performance, and an increased risk of injury. Active recovery, like restorative Yoga or a leisurely walk, can promote blood flow and help repair muscle. Balance intensity with rest to achieve optimal performance and avoid burnout. Rest days are part of the plan.

9. I Thought Restricting Foods Was the Only Way to See Results

I thought a healthy diet meant giving up all the foods I loved. Food restriction can create an all-or-nothing mindset, leading to binge eating or an unhealthy relationship with food. Adopting an 80/20 approach—eating nutrient-dense foods 80% of the time and allowing treats 20%—supports long-term adherence and mental health. This flexible approach helps you stay consistent without feeling deprived, making it easier to maintain healthy habits over time.

10. I Thought Daily HIIT Workouts Were the Most Effective for Fat Loss

High-intensity interval training (HIIT) is effective for cardiovascular fitness and calorie burning, but doing it daily or without enough recovery can lead to overtraining and exhaustion. HIIT places significant stress on the body, and recovery is essential for reaping its benefits. A mix of HIIT, steady-state cardio, and strength training leads to better overall fitness and fat loss. Moderate-intensity exercises also improve recovery and reduce the risk of overuse injuries.

What do most of these have in common? They’re extreme, restrictive, and not sustainable—and that’s the real problem. Isn’t it freeing to know you don’t have to be so extreme to get results?

FITNESS MYTHS HONORABLE MENTIONS:

Here are a few additional misconceptions I considered while putting this post together.

• I thought moderate coffee intake caused dehydration

• I thought sweat and soreness meant I got a good workout

• I thought all processed foods were bad for me

• I thought the more calories I burned in a workout, the better

• I thought cardio equipment and fitness watches displayed accurate calories burned numbers

• I thought 220 minus my age was my actual max heart-rate (not just an estimate that could vary greatly between individuals)

• I thought eating close to bedtime will cause fat gain

• I thought a lower number on the scale was always a good result

• Some people think that running is bad for your knees

• There is misinformation that protein is bad for your kidneys

• Some people think creatine makes you bloated (YouTube Video on creatine for women coming shortly, are you subscribed to my channel?)

Did I miss any fitness or health myths you once believed?

If you've believed these myths, you're not alone. I purposely framed this post in terms of what I have believed over my lifetime so that you understand that I've been there too, so there is no judgment.

But when we know better, we do better. Understanding fitness and nutrition helps us make choices that align with our goals and create a healthier, more sustainable lifestyle. Remember: Fitness isn't about perfection; it's about progress. What fitness misconception are you ready to let go of today?

If you’ve ever felt overwhelmed by all the conflicting health and fitness advice out there, you’re not alone. If you need help wading through the muck of fitness and health, fill out a coaching application, I’m here to help.

Do you know someone who might benefit from this blog post? It helps me when you share with your friends and followers.

Questions? I’d love to help.

Coach Lea

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